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Material Flow Cost Accounting application and its
Integration with Lean Tools
Helena Craveiro Patrocínio Cecílio
Thesis to obtain the Master of Science Degree in
Mechanical Engineering
Supervisor: Prof. Paulo Miguel Nogueira Peças
Examination Committee
Chairperson: Prof. Rui Manuel dos Santos Oliveira Baptista
Supervisor: Prof. Paulo Miguel Nogueira Peças
Members of the Committee: Profª. Elsa Maria Pires Henriques
Profª. Inês Esteves Ribeiro
November 2017
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Acknowledgements
First of all, I would like to express my deep gratitude to my supervisor, Prof. Paulo Peças . His expertise,
guidance, support and motivation, which were crucial to achieving my goals on this important project in
my life. Moreover, I would like to thank him for being always available to share his knowledge with
patience and kindness.
Special thanks to Prof. Uwe Götze and Dr. Rooney Sygulla for share their knowledge, for the availability
and the support during this work development.
I would also like to thanks to the company that welcomed me and allowed the development of my work
which is now completed. Their kindness and support were fundamental for this work. I would like to
express my sincere thanks to Dr. Miguel for his guidance and Sara for the amazing integration process
and for all the support inside the company. I would also like to thanks, to Hugo, Isabel, Joana, Gil, and
all the employees which stops their jobs to support mine.
To my university friends, for always supported me. Especially to Patricia Paiva my favourite Spanish girl
for her friendship and her inexhaustible support shared since the first day we met. To Mary, my almost
twin for all the patience, the support and help during this long journey that is our friendship. To Vivi, for
all the friendship and the amazing talks that makes me fell away of my problems. Thanks to António for
always making me laugh, for all the support and the patience. Also, to my high school friends, Soraia,
Marina, Sara, Camarão, Edu for the availability, help and support during all these years.
I would like to thank my parents from the bottom of my heart, for the unconditional love, for all the
patience, for all support, for always encouraged me to take risks and face the challenges. Thanks for
the ERASMUS opportunity, thanks for always believing in me and the most important thing, thanks for
showing me the real meaning of the word “Familia” (family).
To my sister Joana, for always believing in me and for being the best example that a could ever have.
To my brother João, for always think positive, encourage me to draw my own journey, for never leave
me alone, for always believed in my potential. To my aunts and cousins, and especially to my
grandmothers who unfortunately are looking at me from the heaven but always encouraged me to follow
my dreams.
Last, but not least, I would like to thank João Nuno, for always support me, for always encourage me to
overcome my fears and never allowed me to give up.
“Who walks alone might even get faster,
but one that is accompanied surely goes further”.
Clarice Lispector
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Resumo
Com a emergente necessidade das empresas se tornarem mais competitivas, industrias relacionadas
com a manufatura de componentes tendem cada vez mais a procurar soluções simples e eficazes que
lhes permitam aumentar a produtividade mantendo ou diminuindo o custo inerente. No entanto, no
decorrer das últimas décadas a consciencialização social sobre problemas ambientais tem vindo a
aumentar. Quando confrontadas com esta realidade estas empresas, sentiram necessidade de
procurar soluções que possibilitassem a redução do impacto ambiental das suas atividades a par da
componente económica focando-se essencialmente no controlo e redução de custos associados.
A presente dissertação foca-se na análise da viabilidade da aplicação do Material Flow Cost Accounting
como uma ferramenta de diagnóstico e na integração do Material Flow Cost Accounting com
ferramentas de gestão de produção para eliminação de desperdícios (Lean tools). Esta integração é
possível devido ao fato de tanto o MFCA como as Ferramentas Lean terem como objetivo principal a
eliminação de desperdícios.
Com propósito de se atingir os objetivos acima expostos, o MFCA é primeiramente aplicado a uma
unidade de produção de injeção de moldes. Esta aplicação possibilita o reconhecimento das vantagens
e limitações deste método. Quando associada a uma observação detalhada do processo permite o
reconhecimento de ineficiências inerentes a este que o MFCA por si só não tem capacidade de
reconhecer. Posteriormente é elaborada uma revisão bibliográfica sobre os possíveis aspetos
complementares dos métodos acima mencionados. Tendo por base esses factos uma metodologia de
integração é apresentada e primeiramente validada com a sua aplicação a um caso prático.
Em suma, o estudo apresentado permitiu o desenvolvimento de uma proposta de metodologia de
integração do MFCA com as ferramentas Lean. Esta nova metodologia possibilita a alteração do
sistema produtivo de maneira a que estes componentes sejam produzidos de forma mais ecológica e
com menor nível de desperdícios. Esta metodologia é aplicada como um ciclo de melhoria continua
tendo como objetivo a evolução do processo de produção aproximando-se cada vez mais do ideal.
Palavras-Chave: Material Flow Cost Accounting, Lean tools, Gestão de Produção, Processo de
Injecção de Moldes, Melhoria Continua.
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Abstract
With the emergent need for companies to become more competitive, industries related with manufacture
of components tend to search for simple and effective solutions which allow them to increase productivity
while maintaining or decreasing the cost involved. However, during the last decades the social
awareness about environmental problems has been increasing. When faced with this reality, companies
felt the need to seek solutions that enable the reduction of the environmental impact of their activities
alongside with the economic component focusing mainly on control and reduction of associated costs.
This dissertation focuses in the analysis of the application of Material Flow Cost Accounting as a
diagnostic tool and its integration with production management tools for waste elimination, particularly
Lean tools. This hypothesis is possible due to that both MFCA and Lean tools has as main goal the
waste elimination.
To achieve the objectives previously stated, the MFCA is primary applied to a production unit of mould
injection. This application allows the recognition of the advantages and limitations of this method. When
associated with a detailed process observation it allows to recognise inefficiencies that the MFCA alone
has no capability to identify. Thereafter, a literature review is performed to assess the complementary
aspects of both, MFCA and Lean tools, methods. In order to validate the developed methodology a
case-study was used.
Concluding, the study presented allowed the development of a methodology integrating MFCA and Lean
tools. This novel methodology allows the change in the production system enabling an environmental
friendly and a low-level waste production of components. The methodology when implemented acts like
a continuous improvement cycle so the production process moves closer to the ideal optimized process.
Key-Words: Material Flow Cost Accounting, Lean manufacturing, Production Management
Continuous improvement, Injection Moulding Process.
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Contents
Acknowledgements .............................................................................................................................. iii
Resumo.................................................................................................................................................. iv
Abstract .................................................................................................................................................. v
Contents ................................................................................................................................................ vi
List of Figures ..................................................................................................................................... viii
List of Tables ......................................................................................................................................... ix
Nomenclature and symbols ................................................................................................................. x
1. Introduction .................................................................................................................................... 1
2. Literature Review of Material Flow Cost Accounting ................................................................. 3
2.1. History and fundamentals of MFCA ...................................................................................... 3
2.1.1. Historical Development of Material Flow Cost Accounting ....................................... 3
2.1.2. Principals and Fundamentals of Material Flow Cost Accounting ............................. 4
2.2. MFCA application Methodology ............................................................................................. 6
2.2.1. Energy Flow and Energy Cost Analysis ................................................................. 10
2.2.2. Loop analysis – Recycling processes ..................................................................... 13
2.3. Material Flow and Traditional Cost Accounting ................................................................... 14
3. Company’s description and work’s approach .......................................................................... 16
3.1. The Company’s description ................................................................................................. 16
3.1.1. Production System Characterization ...................................................................... 16
3.1.2. The injection moulding machine and process ........................................................ 19
3.2. Dissertation Approach ......................................................................................................... 22
4. MFCA application in a production system which follows an MTS strategy .......................... 24
4.1. Case-Study’s Preparation.................................................................................................... 24
4.1.1. Quantity Centres determination .............................................................................. 25
4.2. Quantification of the material flows ..................................................................................... 26
4.2.1. Materials determination and classification .............................................................. 26
4.2.2. Procedure Followed to Collect Data in Physical Units ........................................... 27
4.3. Quantification Energy, System and Material Flows in monetary units ................................ 31
4.4. MFCA compilation data for the Calculation model .............................................................. 34
4.5. MFCA application results and its analysis ........................................................................... 35
4.5.1. MFCA results .......................................................................................................... 35
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4.5.1. Complementary analysis based on MFCA results ................................................. 37
4.6. MFCA application conclusions............................................................................................. 41
5. Methodology for MFCA and Lean Tools Integration ................................................................ 43
5.1. MFCA and Lean approaches ............................................................................................... 44
5.2. MFCA-Lean Methodology.................................................................................................... 49
5.2.1. Objectives and Scope Definition ............................................................................. 51
5.2.2. Operational KPIs definition ..................................................................................... 51
5.2.3. MFCA application and KPIs calculation .................................................................. 52
5.2.4. Process mapping: KPIs vs Target Values .............................................................. 54
5.2.5. Critical QC and KPIs identification and Lean tools application............................... 55
5.3. MFCA-Lean Methodology application ................................................................................. 55
5.3.1. Production system and product characterisation ................................................... 56
5.3.2. Objectives, Scope and Operational KPIs Definition ............................................... 56
5.3.1. MFCA application and data gathering .................................................................... 57
5.3.2. Energy, System and Material cost calculation ........................................................ 59
5.3.3. Calculation model ................................................................................................... 61
5.3.3.1. KPI calculation ........................................................................................................ 62
5.3.3.1.1. KPI selection and calculation for QC ................................................................. 62
5.3.3.1.2. KPI selection and calculation for Total Production System ............................... 63
5.3.3.1.3. KPIs vs Target Values ....................................................................................... 63
5.3.4. Critical QC and KPIs identification .......................................................................... 64
5.3.5. Lean application tools ............................................................................................. 68
5.3.5.1. Lean Root-Cause tools application ......................................................................... 68
5.3.5.2. Lean problem-solving solutions application ............................................................ 72
5.4. Methodology application conclusions .................................................................................. 74
6. Conclusions ................................................................................................................................. 75
7. Future Work .................................................................................................................................. 76
8. References .................................................................................................................................... 77
9. Annexes ........................................................................................................................................... I
Annex A - Equipment identification ................................................................................................... I
Annex B - Company’s Teams and departments ............................................................................. III
Annex C - Operating materials – QC and utilisation ....................................................................... IV
Annex D - Employees’ time distribution per QC .............................................................................. V
Annex E – Analysis to reduce the number of mouldings rejected after stops ............................... VII
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List of Figures
Figure 2-1 – MFCA – Flow model example adopted from [3], [13] ......................................................... 5
Figure 2-2 Plan-Do-Check-Act cycle for MFCA implementation adapted from [3], [15] .......................... 7
Figure 2-3 Departments involved in MFCA implementation .................................................................... 7
Figure 2-4 – QC general cost analysis adapted from [3] ......................................................................... 9
Figure 2-5 – Material and Energy flow map, adapted from [2], [13] ...................................................... 12
Figure 3-1 General processes description ............................................................................................ 17
Figure 3-2 Scheme of a screw injection machine [24] .......................................................................... 20
Figure 3-3- Scheme of the injection moulding process adapted from Biswajit, S et al.(2015),[25] and
injection moulding cycle [26][27] ........................................................................................................... 21
Figure 3-4 Approach followed to develop the present work. ................................................................. 23
Figure 4-1 Production of product A – Material flow map ....................................................................... 26
Figure 4-2 – Data collecting procedure ................................................................................................. 28
Figure 4-3 – Auxiliar calculation model approach ................................................................................. 29
Figure 4-4 Flow maps obtained from the MFCA calculation model ...................................................... 36
Figure 4-5 Contribution of each parameter for the QC’s product cost .................................................. 39
Figure 4-6 Contribution of each parameter for the QC’s waste cost ..................................................... 40
Figure 5-1 Sankey diagram of a production system .............................................................................. 45
Figure 5-2 - Complementary aspects and integration opportunity ........................................................ 49
Figure 5-3- Overview of the MFCA-Lean methodology ......................................................................... 51
Figure 5-4 A proposal of QC and Total Production System dashboards output data, the comparison with
Target Values and the performance indicators. ..................................................................................... 54
Figure 5-6- Material Flow model ............................................................................................................ 58
Figure 5-7 – Methodology dashboard for the production system per QC ............................................. 65
Figure 5-8 Methodology general dashboard of Total Production System ............................................. 65
Figure 5-9 Root-cause analysis to the QC-Injection Machine ............................................................... 69
Figure 5-10 Root-cause analysis to the QC-Packaging ........................................................................ 70
Figure 5-11 Root-cause analysis to the Total Production Time ............................................................. 71
Figure 5-12 Cause analysis of the critical value of the total system cost .............................................. 72
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List of Tables
Table 3-1 Equipment allocation based on the production strategy........................................................ 18
Table 4-1 Characteristics of the product A ............................................................................................. 24
Table 4-2 Product A- Auxiliary materials identification ........................................................................... 27
Table 4-3 Part2 QC Injection Machine ................................................................................................... 35
Table 4-4 Production cost distribution per part ...................................................................................... 37
Table 4-5 Added cost per QC and total contribution .............................................................................. 38
Table 5-1- A general description of 8 MUDA ......................................................................................... 46
Table 5-2 Lean Tools description for problem-solving ........................................................................... 46
Table 5-3 Lean Tools description for root cause identification ............................................................... 47
Table 5-4 Lean Tools description for good practices ............................................................................. 48
Table 5-5- KPI recommended for the integration approach and its application .................................... 51
Table 5-6 – General dimensions of the production process and product .............................................. 56
Table 5-7 – Key Performance Indicators to evaluate the performance considering the company’s goals.
............................................................................................................................................................... 57
Table 5-8- Percentage distribution of employees per QC. .................................................................... 59
Table 5-9- QC-Injection Machine ........................................................................................................... 61
Table 5-10 Identification of critical QC and KPI (per QC and TPS) ....................................................... 66
Table 5-11 The contribution of each QC-System within the Total System Cost .................................... 67
Table 5-12 Comparison value between System cost of Packaging and Injection Machine processes. 68
Table 5-13 Setup time after lean tools application ................................................................................ 73
Table 5-14 Final Results after Lean application tools ............................................................................ 74
Table B-9-1-Teams and departments involved in the manufacturing process ....................................... III
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Nomenclature and symbols
Variation
ECA Energy Cost Accounting
EMS Environmental Management System
FP Final Product
IM Injection Machine
KPI(s) Key Performance Indicator(s)
MEFCA Material and Energy Flow Cost Accounting
MFCA Material Flow Cost Accounting
MTO Make-To-Order
MTS Make-To-Stock
PDCA Plan-Do-Check-Act
PP Polypropylene
QC Quantity Centre
SMED Single Minute Exchange of Dies
TPS Total Production System
TV Target Value
WM Waste Management
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1. Introduction
Nowadays, a modern, competitive and environmental concerned society are pressuring companies to
achieve higher productivities with the lowest possible environmental impact [1]. Thus, few alternative
methods have been emerging, to support management decisions in terms of economic performances
and simultaneously consider the environmental impact and production volumes[1], [2]. Under current
circumstances, Material Flow Cost Accounting (MFCA) is considered one of the main tools for
Environmental Management Accounting (EMA). Consequently, MFCA is one of the methods that are
considered an approach which can contribute to pacify the society’s pressure since it allows the harmony
between sustainability and profitability [1].
Material Flow Cost Accounting, according to ISO standard 14051[3], is a management tool which fosters
the transparency of energy and material flows and consumptions. This method has been developed to
support industrial companies on material and energy efficiency and to support management decisions
by presenting the effective value of the company’s waste. Assuming that the economic impact is one of
the most important factors in the company’s environment, MFCA results should motivate managers to
re-consider their strategy in order to increase production efficiency[4].
Lean Management is also recognised as a solution for waste elimination. Its main goal is the
identification and elimination of several types of waste allowing companies to achieve an efficient
customer demand. Furthermore, Lean Management domain is mainly related with physical flows and
do not directly consider, the economic impact of its improvements. It aims to eliminate all types of waste
directly on the manufacturing system by incremental changes working as continuous improvement cycle
[5].
In one hand, MFCA aims to inform the managers of the real waste value and the sub-division processes
in which the product or component had an increased value or a considerable waste cost. On the other
hand, Lean Management tools goals are directly related with physical flow analyses and problem-solving
solutions. Due to the MFCA and Lean tools complementary aspects, arises the hypothesis of integrate
both.
Firstly, MFCA methodology is applied to a Plastic injection moulding system in a Portuguese company.
Then, to support the hypothesis of integration, the MFCA and Lean management complementarities and
gaps are primarily observed to identify improvement opportunities in manufacturing domain during the
MFCA application. Further, to support the hypothesis of integrate MFCA and Lean tools, their
complementarities aspects and gaps of knowledge are studied based on scientific literature. Thereafter,
a methodology to integrate MFCA and Lean management, is presented and preliminarily validated with
a case study.
The present dissertation begins with a literature review about Material Flow Cost Accounting, including
its historical development, its objectives, principles and fundamentals, as well as the methodology
proposed for MFCA application, presented in Chapter 2.
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The main goals of this work and the approach followed is described and presented in Chapter 3, as well
as the company’s description, the characterization of the production system used as case-study.
Moreover, the Injection moulding process, machine and its variables are also briefly described in this
Chapter.
Chapter 4 presents the methodology followed for the application of the MFCA, as well as the product
characteristics and type of production system. Moreover, the calculation model developed for the
diagnosis analysis of the production system is described. Further, the diagnosis of the case-study
production process is performed and the obtained results are presented and analysed. At the end of
Chapter 4, the inefficiencies existent in the production system are presented, discussed and some
improvement solutions are suggested.
In Chapter 5, firstly, a conceptual review related with MFCA and Lean manufacturing tools focusing on
their complementarities is presented. Then, the methodology for integration is organised by presenting
its steps and the final output – MFCA and Lean related KPIs dashboards. Further, the methodology is
applied to a case study developed in an injection moulding production system, including also the
improvement solutions elaborated. This application aims to preliminary validate the presented
methodology. The chapter ends with conclusions about the potential of the presented methodology
based on the results achieved by its application.
Finally, the conclusions and future work are presented.
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2. Literature Review of Material Flow Cost
Accounting
The growing concerned about climate change and material scarcity since the 80’s have been pressuring
companies to perform their activities with the lowest environmental impact possible[6]. Moreover, the
necessity of meeting the requirements imposed about resources consumption and emissions are forcing
companies to improve its practices in this subject. Nevertheless, companies need to remain competitive
in a worldwide market, achieving higher productivity levels[7], [8]. In consequence, managers are facing
the challenge of integrating ecological goals with economic objectives [8]. To answer those requirements
Material Flow Cost Accounting (MFCA) has been suggested by several authors as one of those tools
that can support companies in decision making for economic and environmental improvements [1].
In this context, MFCA is considered a promising approach since it is recognised as a specialised
accounting method and one of the principal tools of Environmental Management Accounting[3], [8].
MFCA presents the comparison costs between positive products (product) and negative products
(waste), allowing the enhancement of material and energy uses efficiency. Once, the cost of waste is
visible it can drive managers to re-plan their strategy. As soon as this strategy is implemented the
resources reduction can be achieved and consequently a reduction of the overall production cost and
environmental impact can be accomplished [4].
The present Chapter is organised as follow. Firstly, a history development of MFCA is presented as well
as its objective, scope, principals and fundamentals. Then the implementation methodology based on
ISO standard 14051[3] is described. Thereafter, a brief discussion between traditional cost accounting
and Material flow cost accounting is presented to provide a better understanding about MFCA
implementation advantages.
2.1. History and fundamentals of MFCA
2.1.1. Historical Development of Material Flow Cost Accounting
The first, and primary, concept of MFCA is the mass balance. It is based on the laws of thermodynamics,
which postulates that the material or the energy in any system cannot be created or destroyed, it can
only be transformed. This, translated to a company’s reality, means that the resources that enter in the
systems of the company, will leave it in the exact same amount, in the form of product or waste; or
increasing the existing stock [6].
The MFCA appears to face the environmental issues, and its subsequent protection measures, which
began to appear in the 80’s. Thus, the MFCA arises from an environmental management project in a
textile company in Southern Germany named Kunert at the end of the 80’s[6]. Though, the original
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concept of the MFCA was developed in the late 90’s at ‘Institut für Management und Umwelt', Germany.
Posterior few pilot projects were initialised in the German industry. Nevertheless, the first breakthrough
of MFCA was accomplished in Japan. Due to the successful results of the first implementations, the
‘Japanese Ministry of Economy, Trade and Industry’, in 2000’s, encouraged the application of the
methodology in more than three hundred Japanese companies. The achieved results lead these
companies to apply the MFCA methodology since then [9]–[11].
Simultaneously, to support the companies on the MFCA application field, the ISO 14000 was developed
in 2007 in Japan. Its primary objective was to standardise the general concept and its framework, for
the application of the methodology in small and medium companies [9]. The methodology was then
improved, and the final version was published in September 2011, as ISO14051 [10], [12].
The MFCA was firstly designed for single processes and organisations. However, it can be extended to
a supply chain, and there are some successful examples of it. Nevertheless, it requires the sharing of
confidential information between all the companies. To overcome the possible issues and lacks, as well
as to support the companies in its application, a new ISO has been developed since 2014, ISO 14052
[10].
2.1.2. Principals and Fundamentals of Material Flow Cost
Accounting
The MFCA is considered as one of the most powerful tools of Environmental management Accounting.
It is also an effective approach to meet the necessity of increase the productivity and reduce the
environmental impact at the same time, through the promotion of the transparency of material and
resources use[3].
The MFCA is characterized for being a flow orientated accounting method that traces and quantifies in
physical and monetary units all the material and energy flows. Furthermore, it compares the costs
associated to the products and the material losses[1]. The applicability of this method is independent of
the type of production system or organization. Its only requirement is that the company uses material
and energy for its activity [3].
The MFCA method divides the entire production system into Quantity Centres (QC). The QCs are parts
or sub-divisions of the manufacturing system where the inputs and outputs must be quantified in physical
and further in monetary units. Usually, these areas corresponds to places where materials are
transformed, or stocked [3],[9]. The QC is the starting point for data collection in physical units in terms
of resources measurements.
For each QC the material and energy used must be measured in physical units. Then, all the information
related to the QCs must be compiled in a flow model. The flow model (Figure 2-1) illustrates the materials
and the energy flows, as inputs and outputs of the QC. It is important to note that the output flows are
sub-divided into material and waste, based on an allocation rule previously selected [3], [13].
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Figure 2-1 – MFCA – Flow model example adopted from [3], [13]
The final flow model of the production system, Figure 2-1, must provide an overview of process in
analysis [3]. Further, this flow map allows the identification of points where the material and energy
waste can occur based on its costs. That, should motivate managers and engineers to re-organize their
strategy or re-plan this QC performance [9], [14].
The base concept of the MFCA, as it was referred, is the conservation law of material and energy.
Considering this principle, and to guarantee that all the flows are accounted, a mass balance should be
performed to the production system per QC individually. The mass balance must consider the material
inputs, the outputs (product and waste), and the inventory stocks fluctuations. This validation is an
essential requirement for the MFCA analysis and is calculated using Equation (2.1) [1], [3].
𝐼𝑛𝑝𝑢𝑡𝑚𝑎𝑡𝑒𝑟𝑖𝑎𝑙 = 𝑂𝑢𝑡𝑝𝑢𝑡𝑝𝑟𝑜𝑑𝑢𝑐𝑡 + 𝑂𝑢𝑡𝑝𝑢𝑡𝑚𝑎𝑡𝑒𝑟𝑖𝑎𝑙 𝑤𝑎𝑠𝑡𝑒 + ∆ 𝐼𝑛𝑣𝑒𝑛𝑡𝑜𝑟𝑦 (2.1)
Nevertheless, some inaccuracies can occur due to some difficulties in the accounting of material which
are not easily quantified probably related to intake of moisture or air, or chemical reactions, among
others. The unexplained irregularities must be further analysed and investigated to appraise its impact
[3].
MFCA considers the production of goods as a system of material’s flow, as can be predicted from
Equation (2.1). MFCA distinguish the movements of materials in [9]:
1. Desired material flow – Movement of material that intend to become part of the final product;
2. Undesired material flow – movement of unintended materials output.
The MFCA point as undesired material flows the flows resultant of [3], [15]:
1. Operating materials as cleaning solvents, chemical catalysts, detergents, lubricants;
2. Material losses during production system and defective products;
3. Material losses due to destructive control tests;
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4. Materials (usually raw material) in Work-In-Process and stock of rejected products due to
deterioration or off-specifications components;
5. Operating materials remaining in the equipment after set-up or maintenance activities that
will not became part of the final product.
For the MFCA point of view there is no sub-process excluded of being a source of loss before it is
subjected to an evaluation, especially when the analysis field is the manufacturing industry[15]. This
extensive search for inefficiencies and sources of waste may lead to the development of action plans to
decrease undesired outputs. The decrease of unwanted outputs entails the reduction of input materials,
influences positively the economic and ecological effects and increases productivity of the company and
its competitive capacity[9].
To conclude, the MFCA describes and evaluates the flow of materials and energy, aiming at the
improvement of the resources. The identification of the sources of waste may lead to its reduction or
elimination, contributing to reduce the demanded resources, as well as the environmental impact and
the production costs [9], [16].
Additionally, the MFCA application and implementation requires an extensive and precise data collection
which may create the opportunity of improving the existing accounting system of the company.
Moreover, it can also provide the required information for future projects [9].
2.2. MFCA application Methodology
The application of the MFCA in an organization, independently of its production field, requires the
implementation of several steps which need the collaboration of multiple departments [15]. Moreover,
the level of detail and complexity of the analysis is dependent of several factors, such as the organization
size, the manufacturing process and the available information. This method can be implemented in
organizations with or without Environmental Management System (EMS). Nevertheless, the
implementation process is facilitated in companies which already have an EMS [3].
The MFCA application method must be considered as a step by step procedure from the knowledge
about the method and its concept, pass through the recognition of the MFCA necessity for the company
and its implementation to evaluate the production system performance [15]. Moreover, decision-making
in companies are typically associated with economic considerations. Regarding that, the MFCA can
support this point by calculating the financial impact of wastes and becoming a useful tool for decision-
making.
If the company already has an EMS, the MFCA PDCA cycle can be included at different stages of the
EMS PDCA cycle. Furthermore, the advantages of the MFCA application will increase if it is constructed
in concordance with a PDCA cycle. Figure 2-2 illustrates an outline of the MFCA implementation steps
together with PDCA cycle in an industrial environment [3].
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Figure 2-2 Plan-Do-Check-Act cycle for MFCA implementation adapted from [3], [15]
MFCA Plan phase
Firstly, the management level personnel should understand the practicability, advantages and value of
the MFCA. The MFCA application effectiveness is strongly dependent of its management support level
[3].
Secondly, the necessary expertise should be determined. The MFCA requires a deep knowledge of the
method and the collaboration of multiple departments as quality, logistic and engineering. (Figure 2-3)
[3].
Figure 2-3 Departments involved in MFCA implementation
Then, the boundary and the time period of analysis should be determined [3], [13]. The scope of analysis
can include a single or multiple process, an entire facility or even a supply chain. Nevertheless, in a first
approach it is recommended the selection of a single process, processes or products with a potential
significant economic and environmental impact within the organization [3], [15].
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Once determined the boundary, the time period of data collection must be determined. This period
should be sufficiently long to consider any significant variation in the process allowing the compilation
of meaningful data. Depending on the production process selected for the analysis, the appropriate
period can be the time needed for a batch of production, a month, one-third of a year, a half-year or
even a year[3] .
Subsequently, the QCs must be carefully selected and defined [3]. The QCs are theoretical units of
MFCA calculation: if the QC are selected too roughly some relevant information about material losses’
location and negative products’ costs may become unclear; reversely, if the QCs are established too
precisely, the MFCA data compilation may be too complex and difficult [15]. Therefore, before
proceeding to the MFCA’s next phase a macro analysis of the system is recommended to assess the
authentication of the defined QC [15].
MFCA Do phase
Firstly, the inputs and outputs of each QC must be identified. Typically, the inputs are raw materials,
operating materials and energy, and the outputs are products, material and energy losses. The energy
and energy loss identification can be estimated separately or included under the material and material
loss, depending of the companies preferences [3].
Secondly, the identified input and output flows of each QC should be used to interconnect all the quantity
centres within the MFCA boundary of analysis in order to achieve a clear characterization of the
production system flow. Thereafter, each input and output should be quantified in physical units. It is
important to note that to perform the mass balance (Equation (2.1) the quantification of the flows must
be convertible into a single standardized unit. Moreover, the inventory changes cannot be omitted from
the balance and should also be quantified in the same standardised unit as well as all the materials
within the MFCA boundary[3]. The MFCA requires the quantification of all the involved materials in the
production process; however, some materials that represents a minimal environmental or economical
contribution can be neglected[3], [15].
The MFCA analysis allows the visualization and quantification of material losses to support management
decision-making. This purpose is achieved by the improvement of transparency of material losses in
physical and in monetary units [2]. Consequently, the next step of the MFCA application is the
conversion of the physical quantification into monetary[3], [15].
The output flows, of positive products and negative products (waste), do not consider exclusively the
material’s cost (Figure 2-4). Since, any production process requires several types of inputs, the analysis
should consider all the costs involved on it. Consequently, the named flow cost which have to be
assigned to the material’s flow (physical units) include all costs which can be related or are cause by
the material flow [2], [3], [15]. MFCA method divides the several types of cost into:
• Material Cost – Costs of main materials, operating or auxiliary materials. The cost of these
materials is calculated by the multiplication of the physical quantity of the specific material
9
by the cost per physical unit of this material during the collecting period [2], [3]. The use of
fixed prices allows a consistent evaluation for all the steps [3].
• Energy Cost – Cost of the energy consumed in each quantity centre. The recommended
procedure to calculate this cost is through the measurement of the consumption, directly
from the equipment and then, multiplying it by the unit cost [2], [3]. However, when the
energy consumed in a QC is difficult to measure, the energy cost should be calculated for
the entire manufacturing process and then an appropriate criterion should be selected to
allocate this value to each QC [3].
• System Cost – Cost of ‘all expenses incurred in the course of in-house handling of the
material flows, except for material costs, energy costs, and waste management costs’ [3] as
labours, transports and depreciation. Moreover, when the system cost cannot be easily
quantified for each quantity centre, an allocation criterion must be selected [3].
• Waste Management Cost – Cost incurred during the material losses handling, as shredding
process. This specific type of costs is totally attributed to the output of material waste [3],
[15].
Figure 2-4 – QC general cost analysis adapted from [3]
The MFCA distinguishes the direct costs from the indirect costs, as other cost accounting system. The
indirect costs as, administrative costs and structure costs, must be allocated by the more appropriate
criterion. In the MFCA context, ISO standard 14051 [3] suggests a two steps procedure for the indirect
cost allocation. First, the indirect costs must be allocated to the QC that they are related to, and then, to
the outgoing flows through a suitable criterion [2], [3].
Once all the information is compiled the required allocation criterions must be defined [15]. For that, a
two steps procedure is recommended:
1. To allocate cost to different QC;
2. To allocate the internal costs of the QC to product and material waste.
According to ISO standard 14051 [3], the most appropriated allocation criterion, i.e. the one that
transmits as close as possible the reality, should be applied to each case.
As explained before, the MFCA aims to support decision-making. Usually the economical evaluations
are based on monetary units. In contrast, the environmental performance assessment is commonly
based on resources consumption. Thus, to support companies in decision’s field financial and
10
environmental aspects and data collection should be performed simultaneously to create the MFCA
calculation model. This calculation model should be developed within the company considering all the
principals and fundamentals previously exposed about the MFCA methodology. Moreover, a three steps
guide for cost calculation is provided by the ISO standard 14051 [3] and includes follow:
1. Calculation of material costs;
2. Calculation and allocation of the remaining costs;
3. Integrated presentation and analysis of cost data.
The third point, corresponds to the results obtained after the MFCA analysis and allow the identification
of the QC with the material losses that are financial or economical significant. Generally, the information
provided by the MFCA may support a large variety of decisions within a company aiming at the
improvement of resources efficiency and economic performance [3].
After the MFCA results had assisted the organization to understand the extent, implications and drivers
of materials uses and losses, the MFCA data should be reviewed to appraise the opportunity of
improving the financial and environmental performances of the system in analysis and, consequently,
of the company [3]. The MFCA calculation model may support the assessment of the future financial
benefits [3].
The improvements suggested as a result of the MFCA analysis can be divided into three main levels,
although there is no specific procedure to face the MFCA typical problems, only some suggestions which
include [15]:
• Management of manufacturing - The MFCA allows the translation of production physical
quantities into production costs, making visible the achieved results.
• Improvements in production departments- The inefficiencies indicated through the posterior
MFCA analysis, can lead to enhancements of the process design or the equipment’s
replacement. The cost estimation in the production system might be partially estimated by the
MFCA.
• Development stages of a new product- The MFCA allows the visibility of the costs impact of the
processes, being an effective tool to evaluate the improvements in cost planning phases.
The assessment of improvements within the company requires the estimation of future costs and
panned views of the process and technologies configurations which are out of MFCA analysis scope
[2]. However, ISO standard 14051 [3], refers that the MFCA can also be used for planning purposes,
although it does not specifies any procedure for cost planning [2], [3].
2.2.1. Energy Flow and Energy Cost Analysis
The MFCA methodology literature reviews generally neglects an exhaustive examination concerned
energy. According to Sygulla et al. 2011 [2], MFCA methodology must be investigated from the
theoretical point of view to appraise the impact of this practice in the overall results Moreover, the
allocation of energy costs under the material flows neglects the information about the consequences
11
and drivers of energy losses. Despite the possibility of evaluating the energy loss due to heat transfer
or vibrations, this is not easily performed and most of the time is ignored from the energy flow point of
view. The identification of energy inefficiencies requires the entire categorization of the energy uses and
the differentiation of desired and undesired energy flows. Therefore, an energy balance must also be
performed [8], [13].
In most of the cases, a representative part of the costs are related to the energy consumed during the
process. The inclusion of an energy balance and ‘transparent’ models to appraise the energy
consumption and use may support the environmental concerns, namely climate changes, and
economical problems as the increasing price of the energy [3]. Subsequently, it is expected that a
detailed analysis of the energy flows and supply may lead to environmental benefits and costs savings
[8].
The inclusion of energy flows in the MFCA methodology, requires an improvement of flow structure
modelling [2]. The traditional material flow modelling should be traced and quantified in physical units
and then, the energy flow model should be outlined. This integration of both flows will result in a refined
methodology, the Material and Energy Flow Cost Accounting (MEFCA)[13].
The improvement of the MFCA through the inclusion of the energy flow analysis might contribute to the
improvement of the energy use, and consequently to the environmental performance of the organization
[8]. According with Bierer & Götze 2012 [13], the MEFCA general procedure is based on the MFCA
steps as 1.Modelling the flow structure, 2.Quantification of the energy and material flows in physical
units, and 3.Quantification of the material and energy flows in monetary units.
During the first step Bierer & Götze 2012 [13] advise for some important considerations. Firstly, there
are two type of modelling energy. On the one hand, the energy flows can be single traced to describe
its orientation for the most common forms of energy used in industry, as compressed air or electricity.
On the other hand, for materials as gas or coal, the material loss of energy conversion should be
evaluated and if it is significant and relevant for the analysis, an appropriate analysis for modelling the
energy flows must be performed, in parallel to a material flows (note that the material in this case is the
gas or coal) [8].
Furthermore, as occurs with the flows of material, the energy flows are defined as being all the energy
transmitted between QC. Thus, the energy that leaves the QC can leave as energy (efficient energy-
product) or energy loss (energy wasted). The efficient energy is all the energy used to produce the
outgoing products (good parts, and wasted parts) [2].
The energy consumption should be measured with specific instruments. Nevertheless, in some cases
the energy output flows have to be estimated or calculated through an energy conservation balance due
to difficulties or impossibilities for the measurement [8]. As it occurs in the quantification of material
flows, an energy balance must be performed to each quantity centre [13].
After that, the costs associated with the production, from all the categories mentioned before, must be
allocated to every material and energy flow described in the flow map. Figure 2-5 presents a flow model
12
for material and energy. Moreover, the system and waste management cost, first should be assign to
the respective QC and then to the QC output flows [13].
Figure 2-5 – Material and Energy flow map, adapted from [2], [13]
As explained before, the MEFCA suggest an individual quantification of flows in physical units. However,
is suggested by MFCA that all types of materials used should be quantified in a single physical unit to
facilitate the quantification and posterior allocation cost [3]. The quantification of material and energy in
the same physical units is not possible since materials are quantified in kilograms and energy in watt-
hour. Consequently a review concerned the allocation criterions for energy and material flows becomes
mandatory [8].
In MEFCA the material and energy cost are direct flow costs, while system and waste management
costs are considered indirect costs. Bierer & Götze 2012 [13], suggests a possible solution to perform
a more detailed analysis of the costs drivers. This includes a distinction between two types of costs:
• Material-Related System Costs – Includes all the expenses incurred by the in-house handling
of material flows, excluding material costs, waste management cots, energy and energy-related
system costs.
• Energy-Related System Costs – Includes all the expenses incurred by the in-house
transformation, generation, and transmission, except of the cost delivery of purchased energies.
The Energy and material related costs can also be allocated through more simple criterions based on
amount ratios. For example, the allocation based on the energy and material cost ratios. Moreover, the
QC can be categorised per type of output (energy or material) and use the rate of that unit to allocate
the output cost of the remaining [8].
The results obtained through the application of the MFCA and energy cost support the evaluation of
alternative process with the improvement of energy-related information and allow the identification of
existent dependencies between material and energy. Moreover, it supports the enhancement of energy
13
and material resource efficiency by the exposure of the financial effect of the use of these resources [8].
The probable benefits of the improvements are totally dependent on the resources flow information and
the effort to perform the MFECA analysis [2]. It should be noted that, the MFECA application
methodology should be refined. Consequently, further investigation activities are required in this field to
enhance the informative value of Energy Cost Accounting (ECA), offering suitable solutions for energy
inefficiencies and planning methods to compare different alternatives for enhance the energy use [13].
The evaluation of both production systems performed in this dissertation, by the application of MFCA,
allocates the energy cost under the material ratio. This decision was taken based on the existent gaps
of information about energy flows. Moreover, within the total production cost the contribution of energy
cost was not representative and consequently a different decision could compromise the significance
and validity of the results.
2.2.2. Loop analysis – Recycling processes
Due to the pressure to have production processes with the lower amount of wasted material, the
companies tend to include in their production units recycling processes. This type of process is
considered as an internal loop of material from the MFCA point of view. It may suggest that this type of
practices is financial and environmental favourable due to the reduction of raw material consumption
and the dispose of materials. However, it is important to note that a material loop is required because
some waste is generated during the process. Moreover, the recycling process, leads to additional costs
[8].
The characterisation flows of systems that include a recycling process is more complex due to the
interdependency of the raw material, as an input, and the output flows. Thus, to overcome these
difficulties Götze et al. 2014 [8] suggests the three following possible solutions
1. To calculate the total costs of all the material flows – The calculation of all the expenses
incurred related to the material flows includes the calculation of the raw material which is
going to be replaced by the recycled material through the corresponding linear equation
system [8].
2. To consider only the additional costs related to the material loop – This solution aims to
facilitate the previous assessment. The exclusive consideration of the additional costs is a
consequence of the fact that the material costs of the cycle will always became a part of the
output product [8].
3. The loop cost is reported separately - This solution aims to report the cost of the loop
independently to appraise the monetary effect of the material’s use inefficiency [8].
The first two solutions assign the costs of the internal loop to the output as a cost of the final product
itself, ignoring the fact that these costs are a consequence of the treatment of undesired materials.
Those solutions may be thought as contradictory with the MFCA and MFECA. To make visible the
14
inefficiencies of the material uses it is suggested the extraction and presentation of the material loop
costs as another additional and independent cost [17].
Despite the fact that the third suggestion may conflict with the MFCA methodology, in the point that this
flow is understood as a cost without a physical unit, it evaluates the material loop flows and identifies
the financial effect of the material inefficiencies. It making visible the material waste consequences which
is the ultimate goal of the MFCA [8].
2.3. Material Flow and Traditional Cost Accounting
The MFCA is a method which was firstly designed to be applied as an evaluation tool to improving the
resources efficiency [8]. Moreover, when it is compared to the Traditional Cost Accounting (TCA) it can
be recognised as a preferable tool. It presents not only the overall accounting performance, but also
points the real value of the material wasted which is commonly assumed as a necessary product loss
by the traditional methods. Consequently, the deep comprehension of their differences can support the
MFCA implementation, presenting its benefits [3].
Considering that, usually the decisions made in companies are primarily based on economic advantages
to increase margin gains, the evaluation of the existing processes and the development of alternatives
ought to be based on their monetary values. Thus, the appraisal, usually are referred to economic
records and reports which are presented by company’s management accounting system and costs.
Traditional Cost Accounting in theory provides a large variety of approaches for cost analysis, although
it largely fails in the in resources inefficiencies identification [8].
The most evidence difference between MFCA and TCA is related to the way that material losses costs
and energy inefficiencies are treated when a process is analysed. From the TCA perspective, the cost
related with material and energy inefficiencies are allocated to the product cost without being
differentiated. TCA considers the material and energy wastes as a necessary part of the production
process [3]. The material costs related to material losses are frequently pre-defined as a standard
number. Then, the current cost of the production systems is compared with previous ones, considering
the fixed value of waste, when a variance is identified its causes are analysed. These values
discrepancy, rather reflect the material losses, it only reveals that the material used is outside the
standards. Consequently, only the ones which are beyond the standards are considered as a loss.
Moreover, the waste management cost is either included in product cost or total cost related to the
production system. All these gaps results in a misunderstanding of the real dimension of the material
losses and energy inefficiencies and its impacts in the overall production system [3].
As it was previously explained, the MFCA traces all the material flows aiming to highlight the material
losses in the processes. To accomplish that goal the material flows are traced and then are treated
separately in terms of outputs – Product cost and Waste cost. These costs include all the associated
costs to transform material in products or in waste, which include the energy cost, waste management
cost, materials cost and system cost. Therefore, they are allocated to the respective outputs through a
15
suitable criterion. The MFCA, in opposition to the TCA, emphases the costs of material losses and the
costs related to inefficiencies in each step of the process, making visible the real cost of unwanted flows
(waste flows). The recognition of the sources of material loss and the more probable source of
inefficiencies supports the companies to enhance the management accounting system, as well as to
evaluate the environmental impacts of their practices [3].
Despite the fact that the MFCA includes and fills the TCA gaps concerning the evaluation of material
losses, the information provided by its application and some objectives are connected to the traditional
methods. Both, MFCA and TCA business analysis, provide relevant information for planning and
controlling operations. They also support the communication between all the employees and the
evaluation of products. However, they use that information differently. While MFCA focus on processes,
by its evaluation in terms of desired and undesired results, aiming in the analysis of the resources
efficiency; TCA uses the information about the cost, typically, to appraise the products’ cost and evaluate
economic performance of the company [8].
Therefore, from the company’s management perspective, MFCA can be recognised as a particular part
of its cost accounting system. Literature proposes an approach to integrate MFCA in the Traditional
Cost Accounting system as a specific data supplier. The proposed integration guarantees the
comparability of the results. The analysis derived from it should be understood as a study of the same
system evaluated from different perspectives, that should contribute for the enhancement of available
information to support decision making. Moreover, is expected that the detailed information about
production process regarding energy and material flows due to the MFCA application will improve the
quality of the traditional costs assessments [8].
As mentioned in the previous chapter, the MFCA analysis requires detailed information concerning the
material and energy consumptions and flows. In turns the collection of that information require their
measurement in physical units in specific points of the production system. Moreover, it is also necessary
to evaluate those physical units and allocate the respective cost to the correct outgoings. This entire
accurate process is required for the MFCA implementation and its validity. When the integration of the
MFCA as a partial system of TCA is suggested, the benefits and the possible enhancements should be
evaluated and contrasted with the necessary effort required for the MFCA application. Finally, the
appropriate implementation strategy should consider a ration between the MFCA required effort and the
TCA final benefits [8].
For the implementation procedure is also recommended, based on several applications, the previous
identification of the critical parts and then, the development of a rough flow model. It is expected that
the MFCA first application highlights the points of inefficiencies. Successful cases from Japanese
companies shows that the MFCA analysis presents more inefficiencies and material losses than the
expected from the company’s managers [3], [15], [17]. The recognition of these issues should motivate
managers to re-plan their strategy in order to eliminate these inefficiencies which may be translated in
relevant costs savings [8].
16
3. Company’s description and work’s approach
The main objectives of the present work consist in the validation of the MFCA’s applicability as a
diagnostic tool. Then, a literary a study concerning MFCA method and the Lean tools complementarities
is performed. Subsequently, based on this study, is aims to develop and methodology to integrate MFCA
method and the Lean and primarily validated it by its application to a different case study
To achieve the dissertation goals the work was partially developed in an industrial company, enabling
the necessary data collection to perform the MFCA analysis and its calculation model. Moreover, when
the MFCA is applied and continuously followed by the person who is applying it, not only, allows an
easily identification of the inherent MFCA’s gaps, but also, enables the recognition of the
complementarity opportunities related to Production management in continuous improvement domain.
This chapter aims to introduce the productive system and the industrial framework where both case-
studies were developed. Thus, the following subsections describe the company where the work was
developed, the productive system characteristics and the manufacturing process. At the end of this
chapter, the approach followed to develop the present dissertation is described.
3.1. The Company’s description
The company, where the present work was partially developed initiated his activity in the 80’s with the
Mould manufacturing unit. Lately, at the end of the 90’s the company extended it activity adding a Plastic
Injection Moulding unit. Thus, the company’s production domain was extended from mould's design and
its manufacture up to the delivery of the finished parts.
The Injection Moulding unit produces essentially components in thermoplastic, producing a large variety
of products for a wide range of industries, as food, automotive and electronics. The unit has 36 machines
and approximately 150 employees. Additionally, to complement the customer services it has several
departments which support the production systems, as logistics, quality, maintenance, assembling and
packaging.
3.1.1. Production System Characterization
The Injection Moulding unit is divided considering the production strategy. Part of this unit is totally
allocated to Make-To-Order (MTO) and the other to Mate-To-Stock (MTS) according to the production
strategy.
The Make-to-Stock (MTS) strategy occurs when the products are manufactured based on demand
forecasts originating an inventory, however if the production system were accurately forecasted it allows
a match between production and inventory preventing extensive stocks [19]. The MTS strategy is the
one selected for the production system of the first case study.
17
The Make-to-Order (MTO) strategy occurs when the products are produced only when the customer
orders it with a pre-defined production volume, avoiding unnecessary stocks [18]. This strategy is used
as a production strategy of the second case-study.
The production system is divided in six mainly activities from the material supply to the customer delivery.
Figure 3-1 presents the activities involved and its brief description considering the sequence of events.
Figure 3-1 General processes description
To perform these activities the company is divided into three main areas, the Warehouse ɪ , the Injection
Moulding, and the Warehouse ɪɪ . Subsequently, these areas are also divided and organized as follows:
• Warehouse ɪ - It is located on the floor below the Injection Moulding and is subdivided into Raw
Material area and Shredding area. Where:
Raw Material Area – It is where the raw material required for the injection moulding process is storage
until it is needed.
• Shredding area – It is where the all the defective parts are storage and shredded to be reused
or sold lately.
• Injection Moulding – It is located on zero floor and is subdivided into Production, Quality,
Packaging, Folder’s Warehouse, Mould’s Warehouse and Discharges zone:
• Production – It is the zone where the injection moulding machines are located and where the
parts are produced. This area is composed by twenty-nine injection moulding machines, 8 for
MTS production strategy and 21 for MTO production strategy.
• Quality – It is an area close to the injection process where the non-destructive quality tests were
performed and is different for each production, i.e., each production has its own quality area.
• Quality Laboratory – It is an area located in one of the sides of the production zone and it is
where the destructive quality tests are performed.
Delivery – The final product is loaded in the customer service.
Material Supply - The material arrives the company as raw material.
Injection Moulding - The components are produce through an injection moulding process.
Quality control - Once per hour one moulding is visually analysed by the quality control
technicians and every four hours a moulding is subjected to a destructive test.
Packaging - The produced parts and the ones subjected to a visual control are packed in
boxes and storage in pallets.
Storage - The pallets are storage in a Final product warehouse until delivered to the
customer.
1
2
3
4
5
6
18
• Packaging – It is an area close to the injection process where the products are packaged. Each
production has its own packaging area close to the respective injection machine.
• Folder Warehouse – It is an area located on the side of the production zone where the
mould/product’s information folders are stored.
• Mould Warehouse – It is an area located in the opposite side of the Folder’s warehouse, and is
where the moulds are storage when the product is not in production. It is also the place where
the mould maintenance team works.
• Discharges zone – It is an outside area where the contaminated material and the discharges
were storage until being sold.
• Warehouse ɪɪ - It is located on the floor above the Injection Moulding and it is subdivided into
three areas:
Final analysis Area – It is the place where samples of products are analysed to guarantee the product’s
quality.
• Final Product warehouse– It is the area where the pallets of packaged products are palletized
and stored until being delivered to the customer.
• Hopper Dryers Area- It is where the hopper dryers are located.
The equipment required for the production system is divided in equipment for manufacturing and
equipment for storage. The allocation of these equipment’ are dependent on the production strategy as
presented in Table 3-1. All the equipment used in this production system are explained in Annex A.
Table 3-1 Equipment allocation based on the production strategy
Equipment MTS MTO
Injection machine
and Mould Dedicated to the production
Chiller Dedicated to the production Shared by all MTO productions
Hopper dryer Dedicated to the production Shared by the MTO productions that
requires the same material at the same time
Vacuum pump Dedicated to the production Shared by all MTO productions
Forklift
Shared by all productions Palletizer
Shredder machine
A similar procedure is followed for the dedicated or not dedicated employees and its tasks. Thus, the
employees and its tasks per MTS strategy and MTO strategy are the following:
The dedicated employees, due to the continuous production characteristic of the Make-To-Stock existing
production, are organized by teams and per shifts. Each shift has an eight hours’ duration and each
team is composed by:
19
• Project manager – Is responsible for all the manufacturing system, thus it is allocated to all the
production system. A project manager it is only responsible for one production and does not
work by shifts. It is also the person that communicates with the administrative department.
• Team Leader – Is responsible for change the raw materials BigBag coordinate the team, solve
the production problems, perform the Injection machine and vacuum pump maintenance and to
pass the information to the next team leader at the end of the shift.
• Dedicated employees – Are responsible for check the raw material supply, weight and pack
the products, check the cycle time and perform the quality tests.
In the Make-To-Order production strategy, there are no dedicated employees. The production also
occurs 24h per day; thus, the employees work by shifts. Each shift has an eight hours duration and each
team is organized as follows:
• Project manager – Is responsible for the same topics as the project manager for MTS
productions, with a difference that in this case it is responsible for all the MTO productions.
• Team Leader – Is responsible for start the productions and consequently the machines,
coordinate the team, solve the production problems and to pass the information to the next team
leader at the end of the shift.
• Leader supporter – His task is to perform the Setup activity, support the Team Leader by
helping him to solve the problems, check the raw material supply and perform the maintenance
activities to each injection machine.
• Semi-Dedicated employees – They are responsible for weight and pack the products, check
the cycle time and perform the quality test, visual and destructive. The employees are semi-
dedicated because they can work in more than one Injection Machine (manufacturing process).
All the information presented above supports the MFCA analysis in terms of data collecting and
company’s organization for posterior flow characterization.
3.1.2. The injection moulding machine and process
As exposed in the second chapter the MFCA is a method that needs a detailed knowledge concerning
all production system variables. Thus, to identify and allocate accurately all the materials and energy
flows it is important to understand the injection moulding phases.
The injection moulding process is the most adaptable process for the manufacture of plastic
components. This process is mainly used in mass production and allows the manufacture of products
with several shapes, dimensions and sizes. Nowadays is considered as the preferable process to
produce three-dimensional products with complex shapes [20].
In 1946 James Watson Hendry, idealised and made the first screw injection machine. The rotational
property of the screw allows a better injection speed control as well as the quality of the manufactured
20
products. This type of machine provided the opportunity of mixing materials (recycled with virgin or multi-
coloured). The screw allowed the reduction of the energy consumption, supporting the plastic heating
process through the friction of the bands. Nowadays the screw injection machine represents
approximately 95% of the injection moulding machinery [20], [21].
There are three types of injection moulding machines: electric, hydraulic and hybrid. Since the products
studied are produced by electric and hybrid moulding machines only these two are explained.
The electric injection moulding machines have been increasing its popularity in the last years. This type
of equipment uses several servo-motors for injection, plasticizing, clamping, ejection and each
sequence is controlled by an independent servo-motor, allowing an energy consumption lower than
hydraulic machines. These machines do not use hydraulic oil; consequently, it consumes less cooling
water to control the oil temperature. Furthermore, the contamination by oils is also reduced, as well as
the noise level [22].
The hybrid injection moulding machine differs from the electric in the point that it has an hydraulic
clamping unit and an electric injection unit, or the opposite. This configuration allows a higher clamp
force when compared with all-electric machine and a lower energy consumption when compared with
the hydraulic machines [21]–[23].
The Figure 3-2, presents a scheme of an injection moulding machine. This machine is composed by two
main parts, the injection unit and the clamping unit.
Figure 3-2 Scheme of a screw injection machine [24]
The injection unit consists in a hopper that feeds plastic granules to the machine, a screw which is
mounted longitudinally in the barrel, a barrel heated by external heaters and a nozzle that connects both
units. The injection unit is responsible for plasticizing, and for the injection [21] [23].
The clamping unit consists in a clamping mechanism, which can be mechanical, hydraulic, both types
or all- electric. This unit is responsible for closing the mould, as well as for maintaining the pressure
inside the cavity during the injection packaging and cooling processes. It is also responsible for opening
the mould and extract the injected component. The clamping force depends on the product projected
area [21], [23].
21
The injection moulding process or usually named as moulding cycle (Figure 3-1) starts with the feeding
of the raw material in the hopper, before its entrance in the screw. At this point, the screw transports the
material into the screw channels, which are located inside of the barrel which in turn is heated by external
heaters. During this process, the material is subjected to the rotational movement of the screw,
contributing to the material mixing. Due to the fact that the material is subjected to high temperatures
and is forced to pass in small areas he is compressed and melted. As soon as the material achieves the
screw tip, the melt retracts against a back-pressure surface allowing the accumulation of a “shot”. The
“shot” is the volume of material that the injection unit needs to inject to guarantee the complete filling of
the cavity. Once the appropriate volume of the shot is obtained the screw finishes its rotational
movement and the injection phase starts [20].
On the injection phase, the screw starts his longitudinal movement, with programmed values of speed
and pressure. When the screw is moved forward, the melt is injected inside the cavity until the cavity is
filled leading to the packing phase. On the packing phase, the screw maintains the forward position
while the material solidifies and contracts. Then a small amount of melt is injected to compensate the
material’s contraction. This step finished the packing phase and initiates the cooling phase. During the
cooling phase the pressure and the temperature decrease gradually inside of the cavity. When the
temperature of the material achieves the ejection temperature, the mould opens, and the product is
ejected. After the mould close and a new injection cycle begins [20].
Figure 3-3- Scheme of the injection moulding process adapted from Biswajit, S et al.(2015),[25] and injection moulding cycle [26][27]
A complete cycle of the mould is designated as moulding cycle time and is one of the most important
parameters in the injection moulding process. The cycle time determines the time to manufacture a part
or group of parts, and it also influences the quality of the parts [28].
The injection process also requires other devices, apart from the mentioned injection machine, as the
mould and its cooling system, and the temperature controllers. The mould is one of the most important
tools. It is constituted by the cavity and the core and is made of stainless or aluminium. Depending on
the product and the machine capacity the mould can have one or multiple cavities which can be equal
or different from each other. The mould also needs a feeding system (runner) which can be of two types:
Moulding Cycle
Plasticization Injection Packing Cooling Ejection
22
hot runners and cold runners. The hot runners’ type is a feeding system divided in two parts, the
manifold, which is responsible for carry the melted material to a point close to the cavity, and the drops,
which carries the material from the manifold to the cavity to feed it. In this feeding system, the runner is
not ejected with the part. In opposition, in the cold runner system, the material of the runners is cooled
and then extracted along with the parts [29][30].
The main difference between the feeding systems presented, are the following. On the one hand, the
hot runners’ system allows a lower cycle time, derived from the fact that only the parts need to be cooled.
Consequently, this type of system presents a lower cooling time; however, its maintenance and mould’s
production are more expensive than the systems that use cold runners. On the other hand, in the cold
runners’ system, the runner is ejected with the part contributing for waste of material [31].
3.2. Dissertation Approach
The approach followed to achieve the goals of the present dissertation is described in this section. It is
subdivided into three phases and schematically presented in Figure 3-4.
The first phase consists in the application of the MFCA to an injection moulding unit which follows an
MTS strategy. This unit uses five all-electric machines and one hybrid, and the moulds have a feeding
system with hot runners. As explained before, the MFCA application requires a detailed characterisation
of the production system aiming to analyse and quantify the material flow involved in physical units, and
lately, in monetary units. This information had to be gathered and posteriorly inputted in the calculation
model developed for the analysis and its results analysed. Due to the necessity of an extensive data
collection, a three moths’ internship was required. The results were presented and discussed with the
company’s managers.
The second phase of this work is based on the careful observation of the same production system. This
detailed observation evinces the existence of some production problems that the MFCA is not able to
transmit clearly in its calculation output due to its nature. Thus, a study of similarities between the MFCA
and the Lean tools was performed to access the viability of their integration. Subsequently, a
methodology to integrate MFCA and Lean tools was developed, proposed and further validated. This
methodology aims to complement both method/tool taking advantage of each other. In one hand, the
MFCA mapping costs and require detailed data gathering, on the other hand, the Lean tools adds
significance information from the production system point of view and ha specific tools for root-cause
and problem-solving analysis.
The combination of these powerful tools will allow the company, not only, the mapping of all production
system’s waste related, but also, it is able to highlight production issues and, using tools for root-cause
analysis to identify the root causes of the problems and propose solutions. After all, the methodology
23
will allow the assessment of the improved results in terms of monetary values and physical
consumptions.
Finally, the methodology is supposed to be used to improve the production process by presenting the
impact and the improvement opportunities in monetary values to motivate managers for a continuous
improving system.
Concluding, the present work aims to validate the previous points described by the application of the
MFCA to a continuous production system to evaluate the benefits of its application as a diagnostic tool
of the production system (Chapter 4). Then, during the data collection for MFCA analysis the production
procedure is also carefully observed and studied to understand the production issues that the MFCA
cannot directly identify. Then, a literature review concerned the identification of complementarities
aspects between the MFCA and Lean is performed. Afterwards, a methodology to integrate the MFCA
and Lean tools is proposed and primarily validated with a second case-study based on MTO strategy.
(Chapter 5).
MFCA application to a production system who follows a MTS strategy.
Based on the careful production system observation some MFCA lacks
scope are identified and primely complemented with Lean tools
To support the observation performed a literature review concerning MFCA
and Lean tools is performed
A methodology to integrate MFCA and Lean tools is proposed and then primarily validated
through its application to an injection production system who follows a MTO strategy
Figure 3-4 Approach followed to develop the present work.
24
4. MFCA application in a production system which
follows an MTS strategy
The company’s production system was generally described in the previous chapter. The two types of
productions were introduced and described, as well as the process used to manufacture the studied
part.
This Chapter presents the methodology followed for the MFCA application, based on ISO standard
14051 [3] . It also explains the required process for the data collection, the calculation model developed
to analyse this production system and the obtained results. Moreover, derived from a careful observation
performed in addition of MFCA some improvement suggestions are presented at the end of this chapter.
4.1. Case-Study’s Preparation
The MFCA methodology for application suggests that firstly, the production system must be
characterised. The characterisation process includes a clear definition of the company’s areas and the
determination of the system boundaries and scope [3]:
1. Specify the boundaries and the product to be analysed;
2. Definition of the time period of analysis and data collection;
3. Determination of the quantity centres.
The product studied is entirely produced by the company, thus the boundary was defined as the limits
of the manufacturing system; i.e. from the material supply until the product delivery to the customer.
Therefore, the boundary conditions are defined at the limits of the production process of the Product,
including human resources and departments involved on the process.
The product, designed in this dissertation as Product A, was selected based on its economic significance
for the company. This product is divided in two components, which are produced separately although
their production is synchronised to guarantee an equal production volume to manufacture the entire pair,
avoiding unwanted stocks. The final product is assembled by an independent company. Both parts are
produced through the injection moulding process, using the same raw material. Although, the raw
material feeding system is the same for the production of both parts each production has allocated
particular machines and moulds as well as employees. The characteristics of the Product A are
presented in the following Table.
Table 4-1 Characteristics of the product A
Parts of the Product A Material Weigh [g]
Part 1- Lid
Polypropylene 2.3
25
Part 2- Cup
Polypropylene 4.2
The time period of analysis was defined as one month to allow the collection of reliable data enabling
the identification of the production’s fluctuations as well as the comparison with the logistic records which
in turns are monthly organized. Once the boundary conditions and the period of analysis are defined,
the following step of the characterisation is the determination of the quantity centres, which is presented
in the next subsection.
4.1.1. Quantity Centres determination
The Quantity Centre (designated as QC) determination is performed based on the process information.
Consequently, is mandatory to analyse and identify all the processes (non-adding value and adding
value) involved in the production system, within the case-study's boundaries.
The MFCA intends to divide the production system into processes or parts, the QC, in which the material
is transformed, stored or contributing for the Work-In-Process. However, if a process does not represent
a significant contribution, it can be included in another QC. To support the QC definition, the production
flow was analysed following the material flow within the manufacturing process.
The manufacture of the product starts in the raw material area when the BigBag is positioned in the
supply zone. Then the raw material flows from the BigBags to the hopper dryer through a conduction
system by the action of a vacuum pump. Then, the material is distributed to the injection machine where
the parts are produced. The parts fall in a conveyor belt and then into carton boxes, which are tagged
and stored in a pallet before going to the warehouse. When the pallet is completed, the employee sends
it to the Final product area where it is palletized. After that, the Final product area’s employee stores the
pallet until it is delivered to the customer.
Figure 4-1 illustrates the material flow map developed based on the production system previously
described. In this flow map the determined QC are showed, as well as the flow of material, in terms of
the input and outputs flows of both parts. The flows are divided in positive and negative product’s flow.
26
Figure 4-1 Production of product A – Material flow map
4.2. Quantification of the material flows
Once defined the quantity, centres ISO 14051 [3] suggests that the inputs and outputs of each QC
should be identified. As explained in the literature review, the usual inputs are divided in material and
energy; and the outputs in product and material loss. For the present case study, the energy and energy
losses are included under the product and the material wasted respectively. For this reason, the energy
flow is included in the material flow and they are traced in the MFCA output as a single one for this
specific case-study.
To quantify the material, flow a two steps procedure was used:
1. Determination and classification of all the materials involved;
2. Data compilation to quantify the flows in physical units.
4.2.1. Materials determination and classification
MFCA classifies the material in two categories, the materials and the operating materials[3]:
MFCA boundary
Product
Waste
Waste
Input
Raw Material
Area
Injection
Machine
Part 1-Lid
Quality
Control
Waste management
(Defective)
Hopper dryer
Packaging
Waste management
(Contaminated)
Injection
Machine
Part 2-Cup Quality
Control
Packaging
Waste management
(Contaminated)
Final Product
Warehouse
Waste management
(Defective)
Input Material flow
Positive product flow
Negative product flow
QC-Production of Part 1 and Part 2
QC-Production of Part 1
QC-Production of Part 2
27
• “Materials” are all the materials which become a part of the final product;
• “Operating Materials” are the materials which do not intend to be part of the product.
The present production system inputs only one material, polypropylene, which is used to produce the
whole product. This material follows the entire production system, and no other raw material is added to
it. However, in the packaging and final product warehouse phases, there are auxiliary materials used to
pack the product (Table 4-2). The cost of the auxiliary materials is allocated to the input flow of the QC
and is part of the QC product output. However, if the amount of auxiliary material wasted was significant,
that amount should be allocated to the material waste flow directly.
Table 4-2 Product A- Auxiliary materials identification
QC Product Auxiliary materials and flow identification
Packaging Part 1
Part 2
Carton boxes and plastic bags with different sizes for
each product, tags with different colours for each
product, adhesive tape, pallets and foam paper. This
auxiliary materials’ costs are added to the respective QC
input flow.
Final Product Warehouse Part 1
Part 2
Plastic film used to palletize the final product pallets. It
cost is added to the QC input flow.
During the production system, the polypropylene is wasted for different reasons:
1. Contaminated parts – Parts which fall out of the conveyor belt;
2. Part 1 Quality control test- Due to the destructive character of the quality control test;
3. Discharges of materials performed after a programmed or non-programmed stop;
4. Products which are out of specification- usually the first twenty shots after a stop of the
machine;
5. Defective parts which are returned from the client.
Subsequently the material’s waste data is inputted in the waste management quantity centre for
contaminated or defective products depending on its the losses nature.
The equipment’s maintenance requires the use of operating materials as alcohol, cleaning solvents,
cleaning cloth, mass etc (Annex C). The cost of these products is assigned to the input flow of the QC
where there are used and is always part of the QC waste output due to its nature.
4.2.2. Procedure Followed to Collect Data in Physical Units
The next phase is the quantification in physical units of each input and output. The ISO norm suggests
that for the material quantification only one physical unit should be selected [3]. Thus, the raw material
is quantified in mass units. However, due to the difficulties founded in measuring the operating and
auxiliary materials in mass unit, these elements are quantified in units of product used, i.e. number of
28
cleaning cloths used in each maintenance, the number of adhesive tape tubes used during the selected
period etc.
The procedure selected to quantify the flows involved has a direct influence on the calculation model
and on the MFCA results. Thus, the data gathering procedure and quantification should be selected
carefully and should be programmed to cause the least possible disturbance to the operators and to the
process. Moreover, this phase is the longest and laborious one, once it involves the communication with
several departments to adapt the data collection time with the working labours time and to adapt the
auxiliary calculation models with the company’s records availability.
In some QC the physical collecting data was not possible or easy to accomplish, as the total production
volume quantification in terms of material consumed and parts produced. To overcome this issue an
auxiliary calculation model was developed for the specific case. The development of the auxiliary
calculation model is further explained.
The procedure followed for the quantification of the input and output flows is divided into two categories:
the Shop floor measurements and the company’s records analysis. The tasks performed are listed and
explained in Figure 4-2.
The first step of the procedure is the BigBag's daily counting in the Raw Material division. Thus, every
day at the same time the number of stored BigBags were accounted to estimate the raw material
consumption value to produce both parts. Based on the fact that during the collection period any
anomaly was detected between the raw material division and the hopper dryer, it is assumed that there
is no waste of material between these points. This assumption is also valid for the material that flows
from the Hopper dryer to the injection machines.
The next steps of the procedure are the machine’s waste weighing, namely the defective parts, the
dischargers and the contaminated components. Thus, depending on the waste nature it was measured
daily or weekly. The defective parts measurement was performed every day at the same time. This
procedure was first performed to assess the accuracy and reliability of company records. At the end of
the first week of measurements, it was possible to conclude that the registers do not transmit the real
Shop floor Measurements Records Analysis
BigBags’ daily counting;
Defective parts daily weighing;
Dischargers of raw material weighing;
Contaminated parts weekly counting;
Operational cavities per mould daily
counting.
Daily production results registered by the
employee (including parts produced, cycle
time each four hours and machine stops);
Internal production management software
data compilation (including cycle time and
machine stops)
Update the developed Calculation Model
Figure 4-2 – Data collecting procedure
29
waste value. Therefore, for the rest of the data collection period it was necessary to weigh the rejected
parts every day. For that purpose, it was asked to the team leader to separate the defective parts of the
two parts of the Product A. The discharges were measured when the maintenance occurred, and the
contaminated components were daily weighted.
The parts destroyed in the quality control test performed to Part 1 were weighted together with the
defective parts. Thus, the amount of waste derived from the quality control test was calculated based
on the developed auxiliary calculation model. The quality control test performed to Part 2 is non-
destructive. After it, they are stored for six months as a batch quality sample and then are delivered to
the customer.
The next step of the procedure is related to the number of operational cavities of each machine. This
value is collected to be further introduced in the auxiliary calculation model to appraise the real
production volume when combined with the cycle time and the machine stops.
The last step is the analysis of the available data existent in a company’s internal software. This software
receives from the machine all the machine’s stop, the real cycle time and the number of components
produced and rejected. Due to incongruences found in the data, only the values related to the stops and
the cycle time were extracted. Once all the data was collected, it is introduced in the Auxiliary Calculation
Model to calculate the real production volume and the total material consumed during the production
process. Figure 4-3 describes the approach of the calculation model.
The Auxiliary Calculation Model calculates the production volume and the material consumed per part
and per machine. The daily production volume of each machine is calculated using Equation (4.1) where
𝑛𝑝𝑎𝑟𝑡𝑠 is the number of parts produced per day, 𝑡𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 is the production time in hours per day, 𝑡𝑐𝑦𝑐𝑙𝑒
is the time required to produce one moulding, and 𝑁𝑐𝑎𝑣𝑖𝑡𝑖𝑒𝑠 is the number of operational cavities of the
mould. The 𝑡𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 is calculated using Equation (4.2) where, 𝑠𝑡𝑜𝑝𝑠 is the time that the machine is not
producing any component. The total amount of good parts produced, 𝑛𝑔𝑜𝑜𝑑 𝑝𝑎𝑟𝑡𝑠, is calculated by
Equation (4.3) where 𝑛𝑑𝑒𝑓𝑒𝑐𝑡𝑖𝑣𝑒 represents the rejected parts, 𝑛𝑞𝑢𝑎𝑙𝑖𝑡𝑦 is the number of parts destroyed
in the quality test, and 𝑛𝑐𝑜𝑛𝑡𝑎𝑚𝑖𝑛𝑎𝑡𝑒𝑑 is the number of contaminated parts. The total amount of consumed
material is calculated using Equation (4.4) where 𝑤𝑒𝑖𝑔ℎ𝑡𝑝𝑎𝑟𝑡 is the weight of each part, and
𝑤𝑒𝑖𝑔ℎ𝑡discharges is the amount of discharged material.
Cycle time
Number of cavities
Rejected parts and Material Weigh
Machine’s stops
Production volume
Material consumed
Figure 4-3 – Auxiliar calculation model approach
30
𝑛𝑝𝑎𝑟𝑡𝑠 = 𝑡𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛[ℎ] × 𝑡𝑐𝑦𝑐𝑙𝑒[ℎ] × 𝑁𝑐𝑎𝑣𝑖𝑡𝑖𝑒𝑠 (4.1)
𝑡𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 = 24[ℎ] − 𝑠𝑡𝑜𝑝𝑠[ℎ] (4.2)
𝑛𝑔𝑜𝑜𝑑 𝑝𝑎𝑟𝑡𝑠 = 𝑛𝑝𝑎𝑟𝑡𝑠 − 𝑛𝑑𝑒𝑓𝑒𝑐𝑡𝑖𝑣𝑒 − 𝑛𝑞𝑢𝑎𝑙𝑖𝑡𝑦 − 𝑛𝑐𝑜𝑛𝑡𝑎𝑚𝑖𝑛𝑎𝑡𝑒𝑑 (4.3)
𝑚𝑎𝑡𝑒𝑟𝑖𝑎𝑙𝑐𝑜𝑛𝑠𝑢𝑚𝑒𝑑[𝐾𝑔] = 𝑛𝑝𝑎𝑟𝑡𝑠 × 𝑤𝑒𝑖𝑔ℎ𝑡𝑝𝑎𝑟𝑡[𝐾𝑔] + 𝑤𝑒𝑖𝑔ℎ𝑡discharges[𝐾𝑔] (4.4)
The 𝑡𝑐𝑦𝑐𝑙𝑒 and the 𝑁𝑐𝑎𝑣𝑖𝑡𝑖𝑒𝑠 are introduced every four hours to provide a result as close as possible to
the reality. The number of good parts produced allowed the calculation of auxiliary materials used per
week, per Part of the product.
The presented calculations were performed every day during the collecting period. After one month, the
global results were compared with the logistic records. The logistic records include the information of
the stock records, number of pallets of each product delivered to the customer as well as the number of
pallets of each part stored in the Final Product Warehouse. The stock records include the raw material
and the auxiliary materials stocks. Consequently, the raw material consumption observed and accounted
was compared with the stock records and number of pallets delivered to the customer during the
established period. In turn, the same records allow the validation of the auxiliary materials used based
on the total amount of pallets delivered and stored during the analysis. Furthermore, the logistic and
warehouse records also supported the calculation of the operating materials consumed. Moreover, the
consistency of the obtained results allowed the validation of the auxiliary calculation model itself and the
quantification of the material flows in physical units, for each QC.
Regarding the operating materials, there are four types of maintenance: shiftily, weekly, monthly and
annually with different characteristics. Therefore, as a first approach, at least two shiftily maintenance
performed by each team leader were accounted and the materials consumed estimated. Then, some
interviews were performed to appraise the materials’ usage discrepancy between each operator, and
finally a meeting with the maintenance responsible to understand the process needs. At the end, this
information was combined with the operating materials records and the material consumed estimated.
The last step of the material flow quantification in physical units is the mass balance within each QC
and in the total production. The material input of each quantity centre and its inventory must be equal to
the output, in terms of product and waste. Once all the material quantities are determined and the
balance is confirmed, the next phase is the material flow quantification in monetary units.
31
4.3. Quantification Energy, System and Material Flows
in monetary units
The physical units measured in terms of input and output must be translated in monetary units for each
QC. The production system cost includes all the monetary expenses incurred to perform the activity.
Consequently, all cost that are associated or generated by the material flow must be allocated to the
respective output flow (product or material waste). According to ISO standard 14051 presented in [3]
the accuracy of the analysis is maximised when all costs are calculated from data available for individual
QC and material flows. However, when this is not possible the cost should be estimated by cost
allocation procedures.
There are four types of costs considered by the MFCA, the Energy Cost, the System Cost, the Material
Cost and the Waste management cost. This section presents the allocation procedure used for Energy,
System and Material cost calculation. The Waste Management cost identified in this production system
are exclusively related to the waste treatment cost within the WM-QC, so it cost is directly allocated to
the WM-QC system and no other allocation criteria is required [3].
Energy Cost
The energy cost was calculated individually for each QC. To calculate this cost firstly the equipment
used in each QC were identified, and its power consumption measured using a specific equipment,
PROVA 6830 power and harmonic analyser. Then, the energy consumed during the production process
was calculated using Equation (4.5), where 𝑃𝑜𝑤𝑒𝑟 𝑐𝑜𝑛𝑠𝑢𝑚𝑒𝑑 is the power consumption measured with
PROVA 6830 in Kilowatt, and 𝑡𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 is the total time that the machine worked. Afterwards, the Energy
cost is calculated using Equation (4.6), where 𝐸𝑛𝑒𝑟𝑔𝑦 𝑐𝑜𝑠𝑡 corresponds to the price per kilowatt-hour.
The energy cost is allocated to the correspondent QC.
𝐸𝑛𝑒𝑟𝑔𝑦 [𝑘𝑊ℎ] = 𝑃𝑜𝑤𝑒𝑟 𝑐𝑜𝑛𝑠𝑢𝑚𝑒𝑑 [𝑘𝑊] × 𝑡𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 [ℎ] (4.5)
𝐸𝑛𝑒𝑟𝑔𝑦 𝑐𝑜𝑠𝑡_𝑄𝐶 [€] = 𝐸𝑛𝑒𝑟𝑔𝑦 [𝑘𝑊ℎ] ×𝐸𝑛𝑒𝑟𝑔𝑦 𝑐𝑜𝑠𝑡[€]
𝑘𝑊ℎ(4.6)
System Cost
The System Cost includes all the expenses related to the production flows excepts material and energy
cost.[3] Thus, the System Cost is calculated using Equation (4.7), where the employee cost represents
the total cost of the involved employees per QC; the Space and the Equipment costs are the rent of the
space and of equipment required for QC.
𝑆𝑦𝑠𝑡𝑒𝑚 𝐶𝑜𝑠𝑡𝑄𝐶 [€] = ∑ 𝐸𝑚𝑝𝑙𝑜𝑦𝑒𝑒 𝑐𝑜𝑠𝑡𝑄𝐶[€] + 𝑆𝑝𝑎𝑐𝑒 𝑐𝑜𝑠𝑡𝑄𝐶[€] + 𝐸𝑞𝑢𝑖𝑝𝑚𝑒𝑛𝑡 𝑐𝑜𝑠𝑡𝑄𝐶 [€] (4.7)
Employee’s Cost
32
The employee’s cost includes the cost of each employee involved in the production system.
Furthermore, they must be allocated to each QC based on the tasks performed. The employees’ cost
allocation is based on the time spent performing a determined task or activity.
Nevertheless, this criterion cannot be applied to the Project Leader, since he is responsible for the entire
production line. Thus, together with the Project leader a valid distribution of his works per QC was
defined. The distribution per QC is described in Annex D and is based on the time spend by the Project
Leader in each QC. The project leader cost is calculated using Equation (4.8), where the 𝐶𝑜𝑠𝑡𝑝𝑟𝑜𝑗𝑒𝑐𝑡 𝑙𝑒𝑎𝑑𝑒𝑟
is his salary and 𝑡𝑎𝑙𝑙𝑜𝑐𝑎𝑡𝑒𝑑𝑄𝐶 is the time distribution per QC.
On the other hand, the costs of the team leader and the dedicated employees are allocated to the QC
using Equation (4.9), where 𝐶𝑜𝑠𝑡𝑒𝑚𝑝𝑙𝑜𝑦𝑒𝑒 is the employee’ cost per hour, the 𝑡𝑒𝑚𝑝𝑙𝑜𝑦𝑒𝑒𝑄𝐶_𝑎 is the time in
hours spent by the employee executing the activity 𝑎 related to the QC, and the 𝑁𝑒𝑚𝑝𝑙𝑜𝑦𝑒𝑒𝑄𝐶_𝑎 is the
number of employees involved in this activity.
𝑃𝑟𝑜𝑗𝑒𝑐𝑡 𝐿𝑒𝑎𝑑𝑒𝑟 𝑐𝑜𝑠𝑡 𝑄𝐶 = 𝐶𝑜𝑠𝑡𝑝𝑟𝑜𝑗𝑒𝑐𝑡 𝑙𝑒𝑎𝑑𝑒𝑟[€/𝑚𝑜𝑛𝑡ℎ] × 𝑡𝑎𝑙𝑙𝑜𝑐𝑎𝑡𝑒𝑑𝑄𝐶[𝑚𝑜𝑛𝑡ℎ] (4.8)
𝐸𝑚𝑝𝑙𝑜𝑦𝑒𝑒 𝑐𝑜𝑠𝑡𝑄𝐶[€] = ∑ 𝐶𝑜𝑠𝑡𝑒𝑚𝑝𝑙𝑜𝑦𝑒𝑒 [€
ℎ] × 𝑡𝑒𝑚𝑝𝑙𝑜𝑦𝑒𝑒𝑄𝐶𝑎
[ℎ] × 𝑁𝑒𝑚𝑝𝑙𝑜𝑦𝑒𝑒𝑄𝐶𝑎
𝑎=1
(4.9)
To obtain reliable data for the calculation model the following steps were performed:
1. Identification of the activities per QC;
2. Identification of the type of employee per activity;
3. Analysis of the perception of the employee about the time spent in each activity;
4. Calculation of the time required to perform each activity and the number of employees involved;
5. Data collection of the salary of each type of employee;
The results obtained through are presented in Annex D.
Space’s and Equipment’s Cost
The Space cost is calculated using Equation (4.10). Then, it is assigned to each QC individually based
on the space required to perform the activities involved as well as the space occupied by the equipment.
Regarding that, the 𝑆𝑝𝑎𝑐𝑒−𝑄𝐶 is the space occupied by the QC in square meters, the 𝑇𝑜𝑡𝑎𝑙 𝑆𝑝𝑎𝑐𝑒 is the
total area rented in square meters and the 𝑅𝑒𝑛𝑡 𝐶𝑜𝑠𝑡 is the value paid for the total area per month.
𝑆𝑝𝑎𝑐𝑒 𝑐𝑜𝑠𝑡−𝑄𝐶[€] =𝑆𝑝𝑎𝑐𝑒−𝑄𝐶 [𝑚2]
𝑇𝑜𝑡𝑎𝑙 𝑆𝑝𝑎𝑐𝑒 [𝑚2]× 𝑅𝑒𝑛𝑡 𝐶𝑜𝑠𝑡[€/𝑚𝑜𝑛𝑡ℎ] (4.10)
The cost calculation and the allocation to the QC were performed based on the following approach:
1. Identify the physical boundaries of each QC;
2. Measure the space occupied per each QC;
3. Rent cost and the total area rented data gathering (source-management department).
33
The Equipment’s cost is allocated considering the type of equipment. There are two different types of
equipment, the dedicated equipment and non-dedicated equipment. The dedicated equipment are those
that are only used to produce the component, as the Injection machine, the weight scale, the conveyor
belt… in that case, the cost of the equipment is its rent or monthly depreciation and is allocated to the
QC where is used. To allocate the non-dedicated equipment to the manufacturing system a different
criterion is used. It is known that the majority of this equipment is stopped during a period of the
production system. However, even though they are stopped, they have an associated cost.
Consequently, the company uses this equipment to support others production systems, and their cost
cannot be allocated to a single production system or even distributed by operational time. Therefore, is
assumed that the occupation of non-dedicated equipment by a production process is proportional to its
production volume. Based on the presented statements an rule based on the total production volume is
selected. Equation (4.11) represents the direct ratio between the 𝑃𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝑣𝑜𝑙𝑢𝑚𝑒𝑐𝑜𝑚𝑝𝑜𝑛𝑒𝑛𝑡 which is the
total production volume of the product, and 𝑃𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝑣𝑜𝑙𝑢𝑚𝑒𝑐𝑜𝑚𝑝𝑎𝑛𝑦 represents the company’s total
production volume. Thereafter the Equipment cost is calculated using Equation (4.12), where
𝐸𝑞𝑢𝑖𝑝𝑚𝑒𝑛𝑡 𝑐𝑜𝑠𝑡−𝑄𝐶 is the equipment’s rent or monthly depreciation and is allocated to the respective
QC.
𝐴𝑙𝑙𝑜𝑐𝑎𝑡𝑖𝑜𝑛𝑛𝑜𝑛−𝑑𝑒𝑑𝑖𝑐𝑎𝑡𝑒𝑑 𝑒𝑞𝑢𝑖𝑝𝑚𝑒𝑛𝑡 =𝑃𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝑣𝑜𝑙𝑢𝑚𝑒𝑐𝑜𝑚𝑝𝑜𝑛𝑒𝑛𝑡
𝑃𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝑣𝑜𝑙𝑢𝑚𝑒𝑐𝑜𝑚𝑝𝑎𝑛𝑦 (4.11)
𝐸𝑞𝑢𝑖𝑝𝑚𝑒𝑛𝑡 𝑐𝑜𝑠𝑡−𝑄𝐶 = 𝐸𝑞𝑢𝑖𝑝𝑚𝑒𝑛𝑡 𝑐𝑜𝑠𝑡 [€/𝑚𝑜𝑛𝑡ℎ] × 𝐴𝑙𝑙𝑜𝑐𝑎𝑡𝑖𝑜𝑛𝑛𝑜𝑛−𝑑𝑒𝑑𝑖𝑐𝑎𝑡𝑒𝑑 𝑒𝑞𝑢𝑖𝑝𝑚𝑒𝑛𝑡 (4.12)
All the allocation rules results are presented in Annex D.
Material Cost
The Equation (4.13) presents the calculation procedure followed for the material quantification in
monetary units. Where 𝑀𝑎𝑡𝑒𝑟𝑖𝑎𝑙[𝐾𝑔] is the total amount of material required to accomplish the specific
task.
𝑀𝑎𝑡𝑒𝑟𝑖𝑎𝑙 𝐶𝑜𝑠𝑡 = 𝑀𝑎𝑡𝑒𝑟𝑖𝑎𝑙[𝐾𝑔] × 𝐶𝑜𝑠𝑡/𝐾𝑔 (4.13)
The collecting data procedure was presented in the previous sub-section and the material cost obtained
through a meeting with the logistics department.
Output allocation
The energy and system costs are allocated to the output product or waste trough the proportion of mass
ratio between the products and material waste, i.e., the energy consumed in each quantity centre is
assigned to the output flow by the percentage of the total production that corresponds to product and
material losses. For example, the energy costs allocated to the material loss are associated with the
production of defective parts. The same logic is followed for the Space and Material allocation to Product
and Waste.
34
The Equations presented above were applied to each QC to develop a calculation model presented in
the next subsection.
4.4. MFCA compilation data for the Calculation model
The following step of the MFCA application is the data compilation for the Calculation model to analyse
the present production system. After having quantified all types of flows in physical units and defined
the criterion for converting them into monetary units and also the input and output allocation rule, the
calculation model organises all the information previously calculated and at the end exports a final output
flow map where the flow costs are shown.
This model should include all the resources used and the respective costs to appraise the economic
flow (between QC) and overall to assess the economic performance of the entire production system. It
ought to characterise the economic flow of each QC including the costs related to the previous ones
and the internal costs, i.e., the energy, system and additional materials costs required to perform the
activity.
The present production system, as it was exposed before, is characterised for being based on MTS
strategy. Moreover, it works continuously during the entire year without significant variations during this
period. Therefore, the obtained information for the production system during the collecting period can
be extrapolated, obtaining the annual analysis of the manufacturing system.
The material flow should be developed following the process flow, i.e. the first QC which must be
quantified is the QC where the production system begins, in this case, the Raw Material area. Then the
quantification process should follow the material flow presented in Figure 4-1. The following steps
present the approach used for the development of the calculation model for a single QC:
1. Calculate the input cost of the QC, based on the material flow. For the 1st QC, the input cost
usually corresponds to the cost of the imputed material.
2. Identify the operating and auxiliary materials that are related to the QC and allocate them to the
respective output flow.
3. Calculate the costs of the materials presented in the previous step.
4. Calculate the ratio between the product and waste to assign the resources.
5. Identify and calculate the Material inventory and its variance in the QC.
6. Calculate the energy and system cost through the criterion defined to the QC;
7. Allocate the energy and system cost to the QC output flow based on the ratio calculated in the
4th step;
8. Calculate the output flow of the QC, divided in product and waste.
To accomplish the analysis of the total production system and its flow, the procedure presented should
be performed for each QC.
35
The following table illustrates the implementation of the presented procedure for the Part 2-QC- Injection
Machine including the input costs (from the previous Part 2 QC -Hopper Dryer), the resource allocation
and the final output costs.
Table 4-3 Part2 QC Injection Machine
Total Product Waste
Cost k€ Allocation Cost k€ Allocation Cost k€
Inp
ut
Previous QC 1526 98.5% 1504 1.5% 22
Operating Materials 10 0% 0 100% 10
Material Stock 0 98.5% 0 1.5% 0
System 286 98.5% 282 1.5% 4
Labour 51 - - - -
Space 11 - - - -
Equipment 223 - - - -
Energy 43 98.5% 42 1.5% 1
Total Cost k€ 1865 1828 37
In the Injection Machine, the majority of inputs are allocated to the outputs by the ratio between the
material and material loss except for the operating materials since they are used to perform the
maintenance, and consequently those materials do not become part of the product.
The calculation model is then obtained through the application of the procedure to all processes. This
analysis presents the cost flow of the entire production process and allows the company to appraise the
process where the waste has the highest value.
As explained before the calculation model results is a flow map where the material flow cost is presented
through the combination of each single QC. Thereafter, this flow map is analysed based on the material
waste costs
4.5. MFCA application results and its analysis
The calculation model is the last step of the MFCA analysis. Afterwards the results obtained ought to be
communicated to the company’s managers. Then the company’s managers might use that information
to support decision-making in order to improve the production system’s financial performance [3] In this
section, the results obtained from the MFCA analysis to the production system which follows the MTS
strategy are presented and analysed.
4.5.1. MFCA results
The flow map is the final output of the MFCA analysis (Figure 4-4) : it presents the economic flow based
on the resources consumed in each quantity centre. The flow map’s main goal is to map the real waste
value and the production economic flow. Thus, it is divided in QC and then each QC is sub-divided in
Input cost, Energy and System cost and Outputs which in turns differentiate the product and material
36
waste cost (Figure 4-4). The present flow model also shows the distribution in percentages between
QCs to allow the analysis however it is not mandatory for the MFCA analysis output.
Figure 4-4 Flow maps obtained from the MFCA calculation model
Form the analysis of the Figure 4-4 is possible to analyse the process or processes within the total
production system where the materials waste increases its cost. The MFCA flow map show that the
single QC with the highest waste cost is the QC – Injection machine of Part 2 wasting 37k€ per year,
38%
62%
99.8%
0.2%
8.8%
91.2%
8.1%
91.9 %
2.1%
97.9%
37
followed by the Quality Control QC of Part 1 which wastes 36k€ per year and then the QC – Injection
machine of Part 1 that generates a waste cost of 34k€.
Moreover, is possible to analyse the Part of the product which represents the highest cost contribution
for the total waste cost. These calculations are performed considering only the waste cost of the Waste
management QCs (contaminated and defective). Following the waste flow (red arrows-Figure 4-4)
individually of each part, the production system of the Part 1 wastes 81k€ per year and the production
system of the Part 2 wastes 45k€ per year.
Furthermore, is also possible to analyse the final cost of the production process per Part. The product
cost of the Part1 production process is 1449 k€ per year and for Part2 is 2051k€ per year, these values
are presented in QC-Final product (output-product) of Part1 and Part2 respectively.
The analysis of the production system is performed based on MFCA output (Figure 4-4) which include
the costs flow of the production system divided per QC. Moreover, to analyse the manufacturing system
a complementary analysis is required, the type of analyse or it scope is not specifically included in MFCA
standard or guidelines; only vague directions are provided as a suggestion of the way that those results
should be presented [3].
4.5.1. Complementary analysis based on MFCA results
The posterior analysis of the MFCA results and possible conclusions, which are not included in the
MFCA output Figure 4-4, is dependent of the analyser abilities to detach some critical points within the
production system and to perform the necessary comparative analysis. The present section aims to
present the analysis performed after the MFCA output and is totally performed by the analyser.
From the MFCA direct results is possible to build further analysis, that depend on the study aims and on
the analyst/company needs. For this case study is important to analyse the primary causes of the
material waste and its financial impacts.
From the values presented in Figure 4-4, is possible to calculate the cost distribution per part that
constitutes the product. For the sum of the product cost of each part, considering the material distribution
after the hopper dryer QC is possible to achieve the cost of the Part 1 and Part 2. Moreover, following
the same procedure is possible to calculate the waste cost per part and consequently for the total
production. These calculations are organised in Table 4-4.
Table 4-4 Production cost distribution per part
Product Cost k€ Product Cost Waste Cost k€ Waste Cost
Part 1 1 449 40,0% 81 2,2%
Part 2 2 051 56,6% 45 1,2%
Total 3 499 96,6% 126 3,4%
The complementary analysis performed based on the MFCA results (Figure 4-4) together with the
observation to the production system allows the identification of some critical points and primary
suggestions for their causes.
38
The complementary analysis of the overall results shows that 96.6% of the total cost is related to the
production of parts with the required specification to deliver to the customer and 3.4% is related to
material losses (Table 4-4).The production of Part 2 represents more 15.6% of the total cost than the
manufacture of Part 1, this value can be a consequence of the Part2 characteristic. Thus, a primary
analysis to assess the cause of this difference pointed that the hopper dryer needs to supply more 1.85
grams of raw material than to produce one Part 1.
Moreover, the cost associated with the material waste is 1% higher in the production of Part 1 then in
the production of Part 2 (Table 4-4), the complementary analysis relates this difference with the
destructive test performed in the quality control of Part1. Furthermore, if the parts production were
analysed separately is possible to assess that: 5.3% of the cost required for the Part1 production is
related to material loss this value is due to the destructive test performed during the quality control of
Part1.
The complementary analysis also identifies the cost contribution of each QC divided in Product and
Waste, and the contribution to the total production cost based on the cost increased in each QC (product
or waste) within the total production cost (Table 4-5). These results are obtained through a cost
distribution, where the Product k€ is related only with the cost of energy, system and material stocked
incurred in the QC which becomes product and the same for the Waste k€.
Table 4-5 Added cost per QC and total contribution
Product k€ Waste k€ Total contribution
Bo
th
Raw Material Area 2 460.6 0 67.9%
Hopper Dryer 2 0 0,1%
Par
t 1
Injection Machine 279.2 33.5 8.6%
Quality control 0 36.6 1,0%
Packaging 217.0 0 6.0%
Waste Management (Contaminated) 0 -0,1 -0,003%
Waste Management (Defective) 0 4.0 0,1%
Final Product Warehouse 18.1 7.3 0,7%
Par
t 2
Injection Machine 297.8 36.6 9,2%
Quality control 34.0 0 0.9%
Packaging 170.0 0 4.7%
Waste Management (Contaminated) 0 -0,1 -0,003%
Waste Management (Defective) 0 5.0 0,1%
Final Product Warehouse 21.0 3.6 0,7% Total Cost k€ 3499.5 126.4
The results obtained, Table 4-5, pointed that in the Raw Material is the QC where the product has the
highest cost representing 67.9%, followed by the Part2 Injection Machine, Part1 Injection Machine QC,
and QC-Packaging of Part1 and Part2.
After the analysis presented in Table 4-5, the cost contribution of each QC-section within the incurred
cost of each QC divided in product and waste is presented in Figure 4-5 and Figure 4-6 respectively.
This complementary study is performed to support the knowledge within each QC which QC-section
39
represents the highest contribution cost and based on that support the stakeholder to re-plan their
strategy.
Figure 4-5 Contribution of each parameter for the QC’s product cost
The Raw Material QC cost is pointed as a consequence of all material required for the product
manufacturing is inputted in this QC. All the cost of the material required represents approximately 98%
of the total Raw Material Cost QC-cost which has a high influence in the production system economic
performance.
The followings QCs with the higher contribution cost are the Part 2 and Part1 – Injection Machine, (Table
4-5) which is considered as comprehensible due to the type of production in studying. The difference
between them is related to the amount of material injected into each production system and also the
depreciation cost of the machines which varies depending on the acquisition cost. Also, the energy
required to produce Part 2 is higher than the required to produce Part1 (Figure 4-5). Those two QC are
the ones that contribute more to the total waste cost, which is directly related to the percentage of the
material wasted since the cost allocation is performed based on the material waste (Figure 4-6). The
material wasted in the production of Part1 and Part2 is distributed as 91% and 92% due to defective
Part1, and Part2 produced respectively and 9% and 8% with contaminated and discharges.
The following QCs with the higher contribution cost are the Packaging for both parts (Table 4-5). This
high value is a consequence of the procedure to pack each part which is entirely performed by the
20%
46%
11%
52%
98%
29%
54%
98,6%
15%
48%
47%
15%
14,47%
1,38%
6%
0,05%
0,5%
65%
4%
0,04%
67%
73%
0,16%
45%
0,14%
0,7%
3%
37%
0,11%3%
13%
0,38%
12%
10%
0% 10% 20% 30% 40% 50% 60% 70% 80% 90% 100%
Final Product Warehouse
Waste Manag.(Defec.)
Packing
Quality control
Injection Machine
Final Product Warehouse
Waste Manag.(Defec.)
Packing
Quality control
Injection Machine
Hopper Dryer
Raw Material Division
Pa
rt 2
Pa
rt 1
Bo
th
Pro
du
ct
Material Operating Materials Employee Equipment Space Energy
Contribution of each parameter for the QC’s product cost
40
employee. The complementary analysis allows the recognition of some issues and some improvement
suggestions were described further. Moreover, the packaging phase is where all the auxiliary materials
were inputted which also contributes to the QC cost.
The complementary analysis performed based on the MFCA flow map aims to present and try to point
the reasons behind the waste cost value. Thus, this analysis pointed the QC-Quality control of Part1
and the Injection Machine Part 2 as being the QCs with the highest cost value. Some reasons behind
the waste cost of the QC-Injection Machine Part 2 were already presented, however, is also important
to refer that this cost is also influenced by the operating material needed for the daily machine
maintenance (Figure 4-6).
The material inputted in the Quality control of Part1 is material wasted, and its high cost comes not only
from the material waste cost but also the fact that this process is performed by the employee once per
hour, thus, his cost is allocated to this process. Moreover, once a shift a quality technician performs the
same test increasing the process cost since a specialised employee requires a higher cost per hour.
The Waste Management of defective components also contributes to the waste cost increase. This
process is required from the customer for design confidentiality reasons, and the company is forced to
grind all defective parts and all returned parts from the customer. Thus, this cost comes from the
employee cost who perform this task and from the machine used.
In the next section, some improvement suggestions based on the complementary analysis performed
are presented.
0,2%
0,5%
3%
3%
48%
0,22%
57%
99%
0,3%
25%
0,95%
10%
0,4%
1,3%
26%
0,05%
31%
0,4%0,1%
1,4%
0,18%
2%
0,2%
0,0% 20,0% 40,0% 60,0% 80,0% 100,0%
Final Product Warehouse
Waste Manag.(Defec.)
Packing
Quality control
Injection Machine
Final Product Warehouse
Waste Manag.(Defec.)
Packing
Quality control
Injection Machine
Hopper Dryer
Raw Material Division
Pa
rt 2
Pa
rt 1
Bo
th
Wa
ste
Material Operating Materials Employee Equipment Space Energy
Figure 4-6 Contribution of each parameter for the QC’s waste cost
Contribution of each parameter for the QC’s waste cost
41
4.6. MFCA application conclusions
The MFCA analysis applied to the product’s production system supports the idea that this method can
be used to assist the company to understand the current state of its production system in terms of
monetary units. In addition, it reveals that MFCA allows an overall understanding about production
system’s cost flow by mapping the material’s movements. Concluding, this method can help to map and
support the analysis of the costs flows as well as the impact of the waste cost in the total production
system.
Before the application of MFCA, the company believed that the waste of material per material input of
this production line was lower than 1%. This is a consequence of company’s traditional cost accounting
method that estimates the waste cost calculation through the comparison between the raw material area
and the final product warehouse data However, when the auxiliary and operating material are included
to the MFCA application, the result obtained shows that the real material waste value represents more
than 3% (2.2% due to Part1, 1.2% due to Part2).
Moreover, this method can be applied as a diagnostic tool when combined with a careful observation to
detect wastes of material and resources during the production system. For those cases some
improvements were suggested:
• Reduce the number of mouldings rejected after stops - The defective parts are a consequence
of the defective products which are produced after the daily maintenance performance that
requires in theory twenty modulations until achieving a specified component. This assumption
motivated a detailed analysis to assess the possibility of material waste reduction.
Consequently, the 5th, 10th, 15th and 20th moulding after maintenance were subjected to a quality
control test. From the analysis of the results obtained was possible to conclude that after the
5th moulding each part met the requirements needed to be delivered to the customer. This
improvement would allow a saving more than one million products per year. (Annex E)
• The quality control destructive test performed to Part 1 is one of the major sources of waste
cost and material waste. Since the samples often present results within the required values,
the test frequency could be redefined. However, this quality control frequency is required from
the customer and consequently cannot be redefined, in that case, is suggested to train the
employees in order to eliminate the test performed by the quality technical, decreasing the QC
cost.
The careful observation of production system combined with the analysis of the MFCA application
allowed the recognition of some technical issues which increase the production cost and material waste.
The results of this analysis suggest that:
• The Hopper dryer QC should be eliminated from the production system. It is a total waste of
resources. This QC is not fundamental to the process, since the material used do not need to
be dryer consequently this QC is increasing the Work-In-Process.
42
• The moulds maintenance should be scheduled to obligate the mould maintenance after a
determined number of moulding. This action will avoid the existence of inoperative cavities
resulting in an improvement in material and energy use.
• The Raw Material aspiration system should be modified since it represents 27% of the Leader
work.
• The packaging phase should also be reformulated since the employees spend more than sixty
percent of their work in this activity. A layout change could be enough to decrease that value
avoiding produced part’s queue to be weight.
The actions suggested should be supported by a cost analysis to assess its consequence on the total
production cost.
The MFCA analysis is a significant tool to evaluate and comprehend the real waste cost and its impact
on a production system. It aims to motivate managers and engineers to re-define their strategy based
on the waste cost and the environmental and economic impact. The MFCA method is concerned about
the reduction of production costs through the decreasing of material consumed that can pass by the
material waste reduction. To perform this analysis a detailed and extensive data is required which could
also be used to enhance the company’s information and accounting system, offering a precise data for
future project decisions. Moreover, it could be a useful diagnostic tool to recognise some production
issues during the analysis and collecting data period when combined with a visual analysis.
The MFCA analysis is able to assess all material and resources waste based on an extensive data and
system characterization but is not prepared to recognise and deals with inefficiencies from the
manufacturing system point of view. In fact, after obtaining MFCA results is necessary to perform several
analysis to be able to conclude the overall performance of the system and its limitations. Moreover, the
extensive data collecting required from the MFCA analysis can be used for further systematic analysis
allowing the easy identification of critical points. This conclusion, and the necessity of a detailed
observation of the production system to propose solutions and assess some root causes of the material
waste motivated a study concerned about the possibility of integration MFCA with Lean tools.
43
5. Methodology for MFCA and Lean Tools Integration
The MFCA is a method to diagnose production systems based on the quantification of the material flows
separating de material used to manufacture the product from the material losses (waste). It allows the
identification of inefficiencies throughout the production system and presents the results regarding
product and waste cost flows. During the development of the first case study, presented in the previous
section, the MFCA allowed the identification of the waste in each QC and the sources of that waste.
Nevertheless, no information is provided about the critical level of those wastes (no target or benchmark
is defined) neither the root causes are systematically identified.
The MFCA maps and quantifies the places (QCs) and the amount of resources consumed, as well as
the material (and energy) losses. However, does not include a procedure for supporting the subsequent
phases of the diagnosis and implementation of improvement measures. Which includes: (i) the
identification of the critical QCs, (ii) the identification of the critical production steps or task in each QC,
(iii) the identification of the root causes of unnecessary resources consumption and losses; (iv) and
finally, the definition of the type solution required.
Thus, as it was referred to the previous case study, the use of Lean manufacturing related tools after
MFCA is recommended for the following reasons:
i) To identify the QC which has a critical value of waste (based on user experience and
its sensibility to assess the results – e.g. the use of Key Performance Indicators (KPIs)
could be useful);
ii) To identify the root causes (e.g. by applying 5 Whys);
iii) To develop a solution to improve the systems’ performance (e.g. Kaizen events, Gemba
walks for simple solutions; 8D problem solving, A3 report for more complex).
The necessity of applying Lean tools after the MFCA analysis motivates this study and its validation.
Despite most of this Lean thinking methods were suggested in the first case study; the impact and
performance of these suggestions were not applied during the internship due to production’s layout
modifications and the transition phase of the manufacturing line.
Consequently, this context motivated the proposal of a methodology which integrates the MFCA and
Lean management tools, taking advantage of their complementarities. On the one hand, MFCA aims to
present to the managers the real monetary value of the waste and the QC within the manufacturing
system that has the highest contribution to the waste cost. On the other hand, Lean Management tools
goals are related to physical flow analysis and problem-solving solutions. Thus, arises the research
question: How to integrate MFCA and Lean management tools for continuous improvement system? To
answer this question, an integration methodology is proposed. Further, is validated through its
application to a case study.
44
The present section is organised as follows. Firstly, a conceptual review related to MFCA and Lean
manufacturing tools focused on their complementarities is presented. Then, the proposed integration
methodology is described. In the third subsection, the methodology is applied to a case study of an
injection moulding system, including also the developed improvement solutions. The case study
application aims a preliminary validation of the proposed methodology.
5.1. MFCA and Lean approaches
Currently, in highly competitive markets and unstable economies, most of the companies in the
manufacturing industry face the challenge of increasing profit margins maintaining the levels of product
quality. Moreover, due to environmental concerns, companies have been pressured to increase the
resources’ efficiency of the processes reducing the material wasted and energy consumed. Such factors
are compelling the manufacturing companies to achieve higher productivity levels at the lowest possible
cost while reducing their environmental impact [1]. In the specific case of the injection moulding
companies, the customers (market) is constantly demanding for more complex parts with a higher level
of components/functions integration. The product’s life is decreasing, lowering gains related to economy
of scale and the technologies levelling worldwide tends to diffuse the type and location of competitors.
This introduces a high uncertainty in the business margins; therefore, the minimisation of production
and lead time, and of the resources consumed is a daily concern.
In this industrial framework, the MFCA is considered as a promising approach to tackle these challenges
[1]. According to ISO norm 14051 presented in [3], MFCA is a management tool that fosters the
transparency of energy and material flows and consumptions, through the identification and
quantification in physical and monetary units of the material and energy flows. In consequence, this
method has been developed to support industrial companies for increasing material and energy
efficiency and supporting management decisions. The MFCA evaluates the positive products (the
product) and negative products (waste-considering all types of losses) separately in order to enhance
the inefficiency of material and energy use and to motivate managers to reconsider their strategy
nurturing an increase of production efficiency. Once the waste cost is visible, the improvement
opportunities may be analysed in detail, elaborated and evaluated and – in the case of positive
opportunity – implemented; aiming at the reduction of resources used and, consequently, the reduction
of the overall production cost and environmental impact [32].
As explained in the literature survey, MFCA is a method of cost accounting which sub-divide the entire
production system in QCs: processes/actions/locals where materials are transformed or stocked and
consequently cause an increase in costs. For each QC, firstly, the inputs and output of positive and
negative products are identified. Then, their quantities are measured (physical units) and afterwards
their costs determined (monetary units). The MFCA data obtained during the analysis is presented in a
material flow cost diagram. It shows the allocated cost per QC, individually, of the total production system
or both Figure 5-1 shows schematically a cost related Sankey diagram is evincing its differentiation
between typical cost input items (material, energy, system cost) and outputs (product, waste cost). For
simplification reasons, the waste management cost is neglected. Finally, MFCA allows to understand,
45
not only, the contribution of each QC in the total production cost, but also evidences the influence of
every QC-section (QC- Material; QC- System; QC- Energy) within each QC.
As it can be concluded, the MFCA shows the performance of each QC, through the mapping of
information related to each QC. This information allows the stakeholders to identify critical processes
based only on the monetary aspect not being able to analyse the criticality level of the QC and its
correspondent QC-Section. This is due to the lack of indicators (within MFCA indicators) able to identify
single QC’s and QC-Section’s contributions for the Total Cost, or any parameter above the expected or
the desired value. Naturally, from the MFCA results the stakeholders can do side calculations to have
that information, however the MFCA do not present directly those indicators.
Having performed the calculations of MFCA, it is necessary to develop solutions and implement them.
The literature on MFCA largely neglects strategies for taking advantage of its detailed and monetary
based diagnosis as procedures of critical aspects’ identification and strategies to develop solutions.
Lean has a different approach for diagnosis and critical aspects identification. While MFCA is essentially
a diagnostic tool and is concerned to make “visible” the monetary value of the production waste, Lean
has a more incisive diagnostic supporting the identification of critical processes/tasks, as well as the
root causes, also including problem-solving tools/approaches. Lean approach is divided in diagnostic
tools, as VSM and Gemba Walk which analyse the production system in a macro perspective without a
direct relation to the monetary value of the processes and/or the production cost [33]. Nevertheless,
these analyses aim to identify the critical processes/tasks to launch continues improvement projects
(based on Kaizen principles – Plan-Do-Check-Act). In fact, the main goal of Lean diagnosis tools is to
identify non-value added activities and analyse them. - Plan phase – aiming to eliminate waste
regardless of its nature (8 MUDA [4] presented in Table 5-1).
Product
(total)
QC1 QC2
Material
cost
Energy cost
System cost
Material losses
cost (QC1)
Material losses
cost (QC2) Material losses (total)
Cost of semi-finished product (QC1)
System cost
Energy cost
Figure 5-1 Sankey diagram of a production system
Cost of finished product (QC2)
46
Table 5-1- A general description of 8 MUDA
Type of MUDA Description
Overproduction Occurs when a company produces more than the volume required for the
customer;
Waiting time When people or products have to wait for a work cycle to be complete;
Motion Any unnecessary movement of machines, people or parts, within the process;
Transportation Any unnecessary movement of machines, people or machines, between
processes;
Rework Occurs when a part is not in concordance with the customer specification and
the part need a correction;
Over Processing Processing beyond the customer standard specifications.
Wasted Talent Unused employee creativity as losing time, ideas, skills, improvements.
The action-plan application accomplishes the effective waste elimination – Do phase – where the
problem-solving tools as Kaizen events, A3 Problem Solving and 8D method (Table 5-2) (from Lean and
Kaizen inter-connection) are used to define cooperatively between the company collaborators. The
intrinsic characteristic of these tools leads to the need of data collection tasks in physical units to analyse
the results (sometimes with consecutive Gemba Walks). These results are then shown regarding non-
added value time (inefficiencies), defective parts, wasted movements, excessive transports…. During
these problem-solving methods supporting tools for root-cause identification are used. Namely, 5Whys,
5W+1H, Is/Is not, Fish-bone diagram, Pareto analysis, Correlation Diagrams, Yamazumi diagrams,…,
presented in Table 5-3. Then solutions are generated aiming to eliminate the root-causes, usually using
good-practices of Lean tools like 5Ss, SMED, Kanban, Mizusumashi, among others, presented in Table
5-4.
Table 5-2 Lean Tools description for problem-solving
Problem Solving
Kaizen event
A long-time team workshop with a specific(s) aim(s) for a critical area. Usually, this
type of events is led by a team leader and must include, training, data collection,
discussion and implementation. In the end, the improved results should be
communicated to the managers. [34]
A3 report
This problem-solving tool is based on the Deming Cycle, the PDCA Method. This
report involves all PDCA phases to problem-solving and continuous improvement.
This format is used to communicate all the relevant information efficiently due to its
high visual impact.[35]
8D method A method focused on product and process improvement to identify, correct and
eliminate issues. The 8D establish a correlative action of the problem and origin of
47
the problem. It is performed by following the 8 Disciplines (Plan; Form a team;
Describe the problem; Interim Containment Action; Root cause analysis; Permanent
corrective action; Implement and validate the previous D; Prevent Recurrence;
Closure and Celebration)[36][37]
Gemba
Walks
A walk to observe where the work is happening (shop floor) to analyse in person the
station or workplace, observing where the work is done and discussing the problems
close to the place. This last statement is performed throughout the interaction with
the employee in order to understand why the tasks are done like he does and finds,
as a team, possible solutions.[38]
Table 5-3 Lean Tools description for root cause identification
Root Causes
5Whys The method involves asking "Why?" five times. The purpose is to move beyond the
various aspects of the problem in order to identify the real cause(s).[39]
5W+1H
A method that involves asking four of the W’s (Who?; What?; Where?; When?) and
the one H (How?) and is used to comprehend the details, analyse the inferences
and judgment to get to the fundamental facts.[40], [41]
Is/Is not
The analysis is performed on board with two columns on cover “is” and “is not”. Thus,
questions like What, Where, When and How big is asked about the problem and the
answer is allocated to the relevant “is” and “is not” column.[42]
Fish-bone
Diagram
A diagram also known as the cause-effect diagram is an analysis that breaks the
“whole” problem in “parts”. Usually, the bones are used to indicate the impact of
causes (the bone's size measures the impact) consequently the larger bones close
to the fish’s head represent an activity or skill with big impact.[43]
Pareto
analysis
A technique based on the 80/20 rule. It is an analysis which separates a limited
number of inputs that represents a big impact on the output. This analysis is based
on the idea that 80% of the problems are due to 20% of the causes. Consequently,
this analysis aims to prioritise a range of items which have different levels of
significance by separate the “vital few” from the “useful many”.[43]
Correlation
Diagrams
A plot of points to study and identify the existence of a relationship between two
variables. It is often used in a follow-up to the fish-bone diagram to identify the
possibility of existing more than two variables between cause and effect.[43]
Yamazumi
Diagrams
A stacked bar chart which categorises the processes individually in Value added,
Non-Value added or Waste. The duration of each task is displayed within the
process’s bar chart and each task stacked to represent the entire process.[44]
48
Table 5-4 Lean Tools description for good practices
Good Practices
5Ss
A tool for organising the workplace in a clean, safe and efficient manner to provide
employee’s productivity and to ensure the standardised work. Based on five
Japanese words all beginning with S – Seiri (Organisation – Separate what is
essential from what is not); Seiton (Neatness – arrange the required items in an
orderly manner); Seiso (Cleaning – keep the workstation clean); Seiketson
(Standardization); Shitsuke (Discipline – follow the procedure).[45]
SMED
Single Minute Exchange of Dies is an approach used for reducing quality losses due
to changeovers. This approach is based on the study and the measurement of the
operations and then suppress on-added operations and convert internal into external
setup, thus try to simplify the design of the machine as well as the trials and
controls.[45]
Kanban
A technique that uses printed cards in a plastic cover which contains specific
information usually a product reference, part number and quantity required. The
word Kanban means “card you can see”. It is used to tell a producer what, when and
how much to produce a part.[46]
Mizusumashi
A person who manages all the logistical work of supply components, materials,
auxiliary materials required. This person gives the materials in small and pre-
established quantities in a specific time avoiding the WIP. This practice also helps to
eliminate the waste of transportation. Usually, this work is performed per
experienced workers, they know where the parts needed are storage and can serve
different workstations.[47]
The Kaizen process continues by assessing the impact of the implementation of the solution and by the
comparison between the expected and achieved results. Usually Lean uses the Visual Management
(VM) to access the production performance during the production time. In some cases, the VM displays
KPIs to assess if the action-plan is allowing the performance previously defined. This procedure
corresponds to the Check phase. After that, a beginning of a new procedure standardisation and
identifying the next critical area and (in case) analyse the aspects of the difference between the expected
and achieved results – Act and subsequent Plan phases.
Despite different approaches to identify wastes and achieve better performance of production system,
MFCA and Lean tools have the same aim and starting point: both analyse the production flow in physical
units and present the actual production performance status. However, Lean is mainly concerned about
reducing MUDAS and MFCA is concerned about the waste economic impact and its reduction based on
its cost. (Figure 5-2). On the one hand, MFCA’s goal is to demonstrate the improvement opportunity by
showing the waste cost but is not primarily designed for problem-solving nor to present specific
solutions. On the other hand, Lean management aims at reducing all types of waste and uses the
49
problem-solving methods and Lean tools to identify the root causes and to provide solutions. However,
is not designed to present the results in monetary units – such as MFCA. Consequently, a methodology
to integrate these two approaches is proposed taking advantage of their complementary aspects.
Figure 5-2 - Complementary aspects and integration opportunity
5.2. MFCA-Lean Methodology
The proposed methodology integrates MFCA structured phases with an adaptable application logic of
Lean tools, i.e., the tools should be selected according to with the production issues. It also incorporates
a very important rationale for the effective success of its implementation: the Kaizen continuous
improvement foundations. The Plan-Do-Check-Act cycle is imbibed in the MFCA-Lean methodology
although is not explicitly mentioned in the methodology sequential phases.
The MFCA-Lean Methodology is composed by the following steps:
• Objectives and Scope Definition:
o The company should define the “macro-level” improvement objectives aligned with their
internal strategy. For example, decreasing of human resources, the material waste,
energy consumption, parts out of specification…
• Operational KPIs definition:
o The MFCA- and Lean-based operational performance indicators should be selected
considering the objectives and scope: MFCA KPIs and Lean KPIs;
o The KPIs derived from MFCA are “mandatory”, the one from Lean are more dependent
on the objectives and scope.
▪ When the MFCA-Lean methodology is applied for the first time is possible that
the company does not have the necessary information about the process to
assign a Target Value to a specific KPI.
MFCA Method Lean Management
Calculation Model in monetary units
Motivate managers by presenting the waste
values
Based on physical units
Root-Causes and problem-solving tools
Present the improvement results in physical units
Manufacturing system
characterization in physical units
Increase efficiency by the waste elimination
Continuous improvement
system
50
o The Target Values for each KPI should be defined, according to with the company
strategy.
• MFCA application and data gathering:
o Application of the MFCA method, namely related to QC definition and related data
gathering;
o Additional data gathering related to the information required for the Lean-based KPIs.
• KPI calculation and process mapping
o Development of a calculation method based on the previously defined KPIs, and KPIs
computing;
o Performance mapping by the use of dashboards with KPIs values for each QC.
• KPIs vs Target Values
o Comparison of obtained KPIs values with Target Values to identify:
▪ The critical QCs – the ones contributing more for the total waste cost
▪ The critical KPIs – the ones with values more distant from the target
• Lean tools for continuous improvement
o Establishment of the opportunity of improvement, selected among the critical QCs
and/or KPIs.
o Considering the nature of the problems, analyse and select an appropriate Lean Tool
to increase the process efficiency, and reduce waste and cost (apply problem-solving
methods and Lean good-practice tools).
Thereafter, the solution definition and implementation, the MFCA should be re-applied considering the
Lean modifications and the potentially improved performance should be confirmed. Subsequently, a new
improvement cycle should begin, aiming to promote a continuous improvement cycle by incremental
changes – the application of the Demming Cycle, also known as PDCA, Plan, Do, Check and Act [45].
51
5.2.1. Objectives and Scope Definition
The first step of the integration approach is the definition of the objectives that should be aligned with
the company’s strategical planning. These “macro objectives” should be the translation of the strategic
objectives in operational performance figures. As an example, for the strategic goal “to be an
environmentally friendly company” or “to reduce our foot-print 20% in the next 2 years”. The subsequent
objective of the methodology application could be “reduction of the energy consumption in the production
line A on 10%” (Another example of application objectives can be: increase the added-value per worker,
or per part produced; the reduction of production costs in a specific amount or percentage, etc).
Furthermore, the scope definition will delimit the production system or part of it where the methodology
will be applied: e.g. a single process, a single product manufacturing line, or the whole production
system. The objectives and scope definition will influence the application process of the proposed
methodology.
5.2.2. Operational KPIs definition
The second step of the methodology is the KPIs identification and selection. A KPI is a management
tool which evaluates the business performance considering the company strategy and goals [33]. A
correct KPI definition allows the methodology to identify the critical points and relevant aspects aligned
with the company’s strategy. These KPIs should reveal the current performance regarding the pre-
established objectives.
According to the context of the present dissertation, the connection of the MFCA and Lean logics to
reduce MUDAs and production costs, some KPIs are recommended in the following table.
Table 5-5- KPI recommended for the integration approach and its application
Application KPI Definition
MFCA
Indicators
Final Output
and QC
indicators
Energy
consumption Cost
Monetary value of the energy consumed during the activity
System Cost Monetary value of the system components (machine
depreciation, employees and space) during the activity
Material Stock
Cost
Monetary value of the material stocked during the activity
Product Cost Value in monetary units of the product
Waste Cost Value in monetary units of production waste
Final Output Total Production
Cost
Cost of the total production
Figure 5-3- Overview of the MFCA-Lean methodology
52
Lean
Based
Indicators
Production Lead
Time
Time required to manufacture an item, from release of an
order to the shipment
Total Production
Time Time required for manufacture the entire order
Material rejected Total Material in Kg that is rejected during the production
activity
Rejected parts Total number of products that are rejected by the
production system
Indicator for
QCs
Associated Cost
Monetary value increased by the inputs in each QC,
caused by the energy, system and material consumption
costs.
Setup time and
cost
The time required to prepare an equipment or system to
be ready to start its task and the associated cost.
Waiting time and
cost
The time that people or parts are waiting for the previous
work cycle time to be complete and the associated cost.
Overall Equipment
Effectiveness
identifies (OEE)
The percentage of productive manufacturing time
considering all losses. The OEE calculation is based on
three factors the Availability the Performance and Quality.
The MFCA indicators (Table 5-5) might be unknown on the first time MFCA is applied so that no Target
Values can be defined. The recurrent use of the proposed methodology, in a Kaizen logic, will allow for
the perception of the aimed values for these KPIs. For a further KPI analysis, the Target Value should
be defined having in mind the figures used for the operational objectives. The Target Value definition
supports the proposed methodology since it establishes a milestone or a numerical goal for each KPI
allowing a better comprehension and evaluation of the current state of the company’s performance. The
Lean based KPIs (Table 5-5) are already applied in many businesses for manage and control systems
allowing a direct definition of Target Values for the corresponding KPI.
5.2.3. MFCA application and KPIs calculation
MFCA methodology should then be applied to appraise the production system current situation.
According to the ISO standard 14051 [3], the method application follows a specific and determined
sequence. For the proposed methodology that sequence was respected and additional tasks are
included aiming to calculate not only the MFCA related KPIs but also the Lean related ones. The steps
are defined as follows:
• Engaging Management
o First, the company management should recognise the practicability of the MFCA in
achieving the organisation's goals;
o Then, should provide the necessary information that is required for the analysis;
• Production system characterisation (defined in the scope):
53
o The scope and boundaries defined should be respected. The time period of the analysis
should also be determined– it should be large enough to take into account the process
fluctuations.
• Definition of QC
o The system should be divided into sub processes where the material passes throughout
a transformation process and/or is stocked, such as storage, production units, quality
control, etc..
• Identification of the inputs and outputs for each QC
o For each QC, the inputs and outputs should be defined. For example, the inputs can be
the materials involved in the process and energy required; the outputs can be the
product and material losses which correspond to nonmarketable products.
• Quantification of the material and energy flows in physical units, and additional QC information:
o Data related to the material and energy flows and human resources data should be
collected in physical units.
o Data gathering about QC performance besides material and energy flows, namely setup
time, waiting times, transports, maintenance time, etc.
• Quantification of the material and energy flows, as well as important operations/tasks, in
monetary units:
o The material and energy flows should be converted into monetary units by information
gathered from financial department or similar sources of information;
o The operations or tasks considered relevant to assess, e.g. setup, waiting,
maintenance, etc., should also be converted to monetary units.
The regular application of a MFCA analysis demands a calculation model to support the organisation to
understand the real waste cost and the consequences of the material used and lost. This calculation
model’s output presents only the “mandatory” MFCA KPIs, thus for the MFCA-Lean methodology, an
output/dashboard modification was performed. This modification allows the stakeholders to analyse
directly from the dashboard the production performance. Those dashboards are presented in detail in
the next section.
54
5.2.4. Process mapping: KPIs vs Target Values
At this point the current state of the production system is well-known, and the results can be analysed.
Aiming to facilitate the overall systems performance two types of dashboards are proposed (Figure 5-4),
one for each QC and the other showing the total performance of the system. Both dashboards suggested
have two main areas, one dedicated to the MFCA indicators, the other to the Lean indicators. Also, they
have a column which connects each KPI with the Target Value, e.g. by showing the direct ratio between
these two figures. Nevertheless, other metrics can be used by the company. The QC dashboard has
more detailed information related to specific operation or tasks, if existent, e.g. setup, waiting time, etc.
This dashboard also shows the contribution of each QC to the overall production cost. The dashboard
related with the total performance has the final MFCA typical indicators of performance as well as the
total cost involved. The contrast between the KPIs observed, and the Target Values indicates the current
state of the process where improvement opportunities might be visible.
Figure 5-4 A proposal of QC and Total Production System dashboards output data, the comparison with Target Values and the performance indicators.
KPI and TV
discrepancy Lean KPIs
Auxiliary data for KPI calculation
MFCA
MFCA
Lean KPIs
Auxiliar data
55
5.2.5. Critical QC and KPIs identification and Lean tools
application
Then, the determination of the critical QC and the critical KPIs can be made by the analyst or the team
through the observation and analysis of the dashboard. Several strategies can be followed,
nevertheless, in the present work is suggested the following.
• Identify the KPIs with “higher distance” to the Target Values, and consider them as critical;
• Identify the QC(s) with higher “QC associated cost” KPI and consider it(them) critical even
though the distance to the Target Value is small;
• Identify in the critical QC(s) the KPIs that most contribute to the bad performance (waste-, time-
, energy-related) and consider it as critical.
The selection of the critical QCs and KPIs allow on efficient and effective subsequent phases of root-
cause analysis, and solutions development and implementation. As proposed by the Kaizen philosophy,
the continuous improvement process should be accomplished by a step-by-step approach, launching
“only” a localised project with very specific objectives at the time.
Hence, the critical QC or QCs must be analysed in detail to understand the reasons behind the crucial
aspect through the application of the Lean diagnostic tools already mentioned. Therefore, an
improvement strategy can be defined through the appropriate problem-solving method. Finally, the Lean
tools for continuous improvement should be performed and the improvement results confirmed. For
example: If the issue is related with the OEE, then Availability, Performance and Quality performance
should be analysed. Moreover, If the problem is related to quality related KPI, the 5Whys method should
be used to achieve the root cause(s) for defective products and Kaizen events, A3 report or 8D problem-
solving methods should be applied. Furthermore, if the issue is related to the setup time KPI, the SMED
and 5s Lean tools can be implemented to eliminate wastes that result from a non-organized work area
or even to convert the internal activities to external and eliminate non-essential operations creating a
standardized setup work; if the critical KPI is related with the waiting time an A3 report or 8D method
can be developed to minimize waiting times.
Concluding, a Kaizen based strategy provided by the application of Lean tools should be performed,
and the improved results should be analysed by the reapplication of the proposed integrated
methodology.
5.3. MFCA-Lean Methodology application
This section presents the MFCA-Lean methodology application and is organised as follows. First, a brief
characterisation of the production system is presented, followed by the presentation of the objectives
defined by the company and the KPI selected for the study. Thereafter, the methodology for the
application of MFCA is presented, and the calculation model explained. Subsequently, the analysis of
the obtained results through the application of the MFCA is presented, followed by the KPI and Target
56
Values analysis. Finally, the solutions suggested, and the improvements achieved from to the application
of the Lean improvement solutions are described and discussed.
5.3.1. Production system and product characterisation
The production system selected to validate the methodology presented was developed in the same
injection moulding company as the first case study. Consequently, all the steps related to MFCA
collecting data are the same as presented in detail in section 4. The production is characterised by being
a Make-To-Order production which has been characterised in section 3. In contrast with the previously
presented case study, this production has not dedicated employees and machines/equipment.
Consequently, the system cost allocation follows a different perspective which is shown in the following
sections.
The manufacturing process was already described in section 3, thus only a brief description is
presented. The production process in study is divided into four main steps. The first is the Injection
Moulding process where the raw material is transformed into final product, then the product is subjected
to a quality analysis and then packed. Afterwards, the product is packed and stored until the client
delivered.
To understand the calculation model and the methodology application the characteristics of the product
are presented in Table 5-6, as the moulding’s constituents, the respective weight and the expected
duration of each cycle, as well as the total production volume. For confidentiality reasons only, the
necessary values are presented, and the part configuration cannot be displayed.
Table 5-6 – General dimensions of the production process and product
Units Weight
Parts per moulding 4 parts 2.12 g/part
Runners per moulding 1 4.1g/moulding
Production lot size 36000
Theoretic cycle time 12.3 sec/ moulding
The methodology applied to the production system is present in the next section.
5.3.2. Objectives, Scope and Operational KPIs Definition
The starting point is the objectives and scope definition. Therefore, the company defined as its main
goal the increase of profit and the reduction of material, energy and human resources. Then, the scope
was defined as the entire process from the material supply until the product delivered.
The next step of the methodology is the definition of the appropriate KPIs. Table 5-7 presents the
appropriate KPIs to analyse the current state of the production system considering the company’s
57
objectives. Since one of the objectives defined was increase the gain margin, the Total Production Cost
was selected as KPI to confirm and evaluate the actual cost. Then, considering the second goal, the
material reduction, the waste material was selected to provide the current performance to evaluate the
deviation between the real value and the expected to appraise improvement possibilities. To evaluate
the possible reduction of human and energy resources and its impact three different indicators were
selected: i) the Total System since the human resources cost is included on it; ii) the OEE which evaluate
the equipment performance and availability that is related to the energy consumption and labour’s work
duration due to the production time; iii) and the Set-up time which analyse directly the labours and
equipment occupation during a period that no product is produced.
The following phase is the Target Value definition/attribution presented in Table 5-7. This value can vary
according to the production characteristics. For this particular case, there is not yet Target Value for the
total production cost and for the total system cost because it was the first time the MFCA was applied.
For the total amount of material waste, the 3% of Target Value represents an average value aimed by
the company, including the material wasted due to discharges, material needed for replacement and
parts needed for the quality control destructive test. The definition of the Target Value for Set-up time
was based on an estimated value that has resulted from company’s previous study. The OEE is defined
based on the company experience, at this point the company aims to achieve at least 65%. This value
represents what they consider as a reasonable value for this parameter.
Table 5-7 – Key Performance Indicators to evaluate the performance considering the company’s goals.
Objective KPI Target Value
Increase the profit
Total Production Cost Undefined
% Material Waste <3%
Reduce the resources uses
Total System Cost Undefined
OEE >65%
Setup time <1h30min
The Target Values presented in Table 5-7are used to evaluate the current state of the production system
based on the aimed results it will support the Check phase of the cycle. This evaluation is presented in
the methodology dashboards for final results, section “KPI and TV discrepancy”.
The following section presents the method applied, and the calculation model developed based on the
information submitted above.
5.3.1. MFCA application and data gathering
To perform MFCA analysis, the steps presented in section 4 were followed. Firstly, the data collection
period was established as one production bunch, i.e. the time required to produce the total order (36
000 good parts). Then, the production system was sub-divided in QC, and the material flow was
58
analysed. Figure 5-5 illustrates a material flow map, where the QC are identified as well as the inputs,
positive product and negative product flows.
Once defined the QC, the inputs and outputs should be quantified in physical units. As explained before
each quantity centre identifies three different parameters, namely, the Material Stock, the Energy
consumption and the System. Consequently, the material consumption and energy were measured. On
the one hand, the material used was weighted and, on the contrary, the energy consumed was measured
directly from the machines. Then, the parameters of the third component, equipment and human
resources, were allocated by the total dedicated time to this particular production.
To analyse the MFCA inputs and outputs in physical units, an extensive data is required about the
following aspects:
• Raw Material – The amount of in Kg and the operating materials used in each QC.
• Material Stock – The amount of the material which is stored in each QC in Kg;
• Energy Consumption – The amount of energy consumed by each machine in each QC in KW
and subsequently the total working hours
• System:
o The employees - The total time for each employee/ leader and Project Manager
dedicated to the production to allocate its cost to each QC.
o The space – The total space in square meters required by the production (space
occupied by the machine; the packaging; the Raw Material…) allocated to each QC.
o The Equipment – The total time that the equipment was occupied for the current
production to allocate its cost to each QC.
Thus, is necessary to define a cost allocation criterion for each type of cost: material, energy and
system, these allocations are described in the next section.
Input
Raw material
area
Hopper dryer Injection
Machine
Packagin
g
Quality
Control
Final Product
Warehouse
Waste management
Product
Waste
Input Material flow
Positive product flow
Negative product flow
MFCA boundary
Figure 5-5- Material Flow model
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5.3.2. Energy, System and Material cost calculation
For the present production system, the Energy and Material cost quantification in monetary units follows,
not only, some of the criterion used for the previous study, but also the procedures developed to collect
the data. That can only be applied due to the processes similarities. Both products are produced through
an injection process and also the Equations used for the previous chapter’s cost calculation retracts the
reality of the present study. However, due to the production strategy the quantification system cost must
be adapted, and the production time is considered as a variable.
Energy Cost
The Energy cost is calculated through two steps. First the power consumed is measured, and the energy
required calculated using Equation (4.5). Then, the Energy cost is calculated by the Equation (4.6),
where is considered the energy consumed by the production system and the energy cost per kilowatt-
hour.
System Cost
The System cost is defined as being the sum of all expenses incurred during the production system,
namely the employee cost, the space cost and the equipment cost. Thus, it is calculated through the
Equation (4.7) presented in the previous chapter.
Employee’s Cost
The present production has not dedicated employees so each employee can have different tasks and
can be involved in different QC. To evaluate the contribution of each employee to the correct QC the
procedure described in section 4.3 is followed. Thus, a time distribution was performed considering the
total dedicated time within the production system (Table 5-8)
Table 5-8- Percentage distribution of employees per QC.
QC Project
Manager
Leader Leader
Assistant
Worker Warehouse
Employee
Raw Material 2% 8% 2%
66%
Hopper Dryer 1%
92%
Injection Machine 60% 92% 6% 5%
Quality Control 17.5%
Packaging 17.5%
93%
Final Product
34%
Waste Management 2%
2%
100% 100% 100% 100% 100%
The Project Manager and Leader allocation costs are calculated using Equation (5.1), where the
𝑐𝑜𝑠𝑡𝑝𝑟𝑜𝑗𝑒𝑐𝑡 𝑚𝑎𝑛𝑎𝑔𝑒𝑟 is the project manager or Leader cost per hour, the 𝑁𝑟 𝑜𝑓 𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛𝑠 is the number of
manufacturing systems that they are responsible for and the 𝑡𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 is the total production time.
60
Then, the Leader assistant, worker and warehouse employee allocation costs are obtained by Equation
(5.2), where 𝑐𝑜𝑠𝑡𝑒𝑚𝑝𝑙𝑦𝑒𝑒 is the employee cost per hour, the 𝑡𝑒𝑚𝑝𝑙𝑜𝑦𝑒𝑒 the time in hours spent by each
employee to the QC, and 𝑁𝑒𝑚𝑝𝑙𝑦𝑒𝑒𝑠 is the number of employees involved in a particular activity related to
the QC.
𝑃𝑟𝑜𝑗𝑒𝑐𝑡𝑚𝑎𝑛𝑎𝑔𝑒𝑟
𝐿𝑒𝑎𝑑𝑒𝑟𝑐𝑜𝑠𝑡[€] =
𝑐𝑜𝑠𝑡𝑝𝑟𝑜𝑗𝑒𝑐𝑡 𝑚𝑎𝑛𝑎𝑔𝑒𝑟/𝑙𝑒𝑎𝑑𝑒𝑟 [€/ℎ]
𝑁𝑟 𝑜𝑓 𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛𝑠 × 𝑡𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 [ℎ] (5.1)
𝐸𝑚𝑝𝑙𝑦𝑒𝑒 𝑐𝑜𝑠𝑡[€] = ∑ 𝑐𝑜𝑠𝑡𝑒𝑚𝑝𝑙𝑦𝑒𝑒 [€/ℎ] × 𝑡𝑒𝑚𝑝𝑙𝑜𝑦𝑒𝑒[ℎ] × 𝑁𝑒𝑚𝑝𝑙𝑦𝑒𝑒𝑠 (5.2)
Space’s and Equipment’s Cost
Space and equipment costs are calculated using Equations (5.3) and (5.4) respectively. The Space cost
is assigned to each QC individually based on the space required to perform the activities involved as
well as the space occupied by the equipment. Regarding that, the 𝑆𝑝𝑎𝑐𝑒−𝑄𝐶 is the space occupied by the
QC in square meters; the 𝑇𝑜𝑡𝑎𝑙 𝑆𝑝𝑎𝑐𝑒 is the total area rented in square meters; the 𝑅𝑒𝑛𝑡 𝐶𝑜𝑠𝑡 is the value
paid for the total area per hour, and the 𝑡𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 is the total production time in hours. Then, as presented
in section 4.3 the equipment cost is calculated based on the type of equipment (dedicated or non-
dedicated) for non-dedicated equipment the equipment cost is calculated using Equation (4.12)
considering the allocation criterion, Equation (4.11). Then, for dedicated equipment the Equipment cost
is allocated considering the 𝐸𝑞𝑢𝑖𝑝𝑚𝑒𝑛𝑡 𝑐𝑜𝑠𝑡 per hour that corresponds to the depreciation or rent value
per hour of the equipment required in each QC.
𝑆𝑝𝑎𝑐𝑒 𝑐𝑜𝑠𝑡−𝑄𝐶[€] =𝑆𝑝𝑎𝑐𝑒−𝑄𝐶 [𝑚2]
𝑇𝑜𝑡𝑎𝑙 𝑆𝑝𝑎𝑐𝑒 [𝑚2]× 𝑅𝑒𝑛𝑡 𝐶𝑜𝑠𝑡[€/ℎ] × 𝑡_𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛[ℎ] (5.3)
𝐸𝑞𝑢𝑖𝑝𝑚𝑒𝑛𝑡 𝑐𝑜𝑠𝑡−𝑄𝐶[€] = 𝐸𝑞𝑢𝑖𝑝𝑚𝑒𝑛𝑡 𝑐𝑜𝑠𝑡 [€/ℎ] × 𝑡𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛[ℎ] (5.4)
Material Cost
The Material cost for this production system is calculated using Equation (4.13). Moreover, the Injection
machine QC in this case study has a particularity which is a consequence of the mould design. The
mould used for manufacturing this product produces four parts and one runner. The runner is a waste
considering the MFCA rules/principles since it causes system and energy resources consumption.
Consequently, the allocation criterion for the waste components in the QC corresponds to the total
amount of material loss (7.37% of defective parts and 30.21% to the runner’s production for the
manufacture of 36028 right parts).
Output allocation
The material, energy and system costs were allocated to the output product and waste in the same way
presented in section 4. The energy costs allocated to the material loss are associated with the production
of defective parts, i.e., the energy consumed in each quantity centre is assigned to the output flow by
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the percentage of the total production that corresponds to product and material losses. For example, in
the Injection Machine, Table 5-9, 37.58% of the energy resources is considered waste because this
percentage corresponds to the material used to produce defective parts and for the runner produced
which is mandatory for the production of good parts. The same logic is followed for the Space and
Material allocation to Product and Waste.
Table 5-9- QC-Injection Machine
Output
Product 390.34 € Waste 237.58 €
% € % €
Inp
ut
Previous QC 509.41 € 62.42% 317.96 € 37.58% 191.45 €
Operating Materials 2.55 € - % - € 100.00% 2.55 €
Stock - € - % - € 100.00% - €
System 100.39 € 62.42% 63.69 € 37.58% 38.35 €
Energy 13.92 € 62.42% 8.69 € 37.58% 5.23 €
The Equations presented above were applied to each QC to develop a calculation model presented in
the next subsection.
5.3.3. Calculation model
The calculation model development was obtained by the combination of the typical MFCA calculation
model, presented in section 4, and the KPI defined, shown in Table 5-7.
The original MFCA calculation model integrates the information related to costs and material flows data
and has as outputs the monetary value of the product and the waste separately, to evaluate the
economic state of the manufacturing system. The MFCA-Lean methodology adds to the original
calculation model the necessary and relevant information in physical units to evaluate the operational
performance through the KPIs analysis of the production system. The following steps present the
calculation process of the model:
9. Material
a. Calculate the main material input in the 1st QC, in Kg and €.
b. Characterize the input and output of each QC by the proportion of positive and negative
product quantities and identify in physical units those quantities
c. Detect and calculate the operating material involved and assign them to the correct QC.
10. Energy
a. Calculate the energy cost and energy consumption of each equipment in each QC in €
and kW respectively.
b. For the present work, the energy cost and consumption were allocated the energy cost
and consumption by the proportion of positive and negative product quantity.
62
11. System
a. Calculate the cost of time spent by each employee in each QC.
b. Calculate the cost of the space needed for the production
c. Calculate the equipment cost during the production
d. Allocate the system cost as the same way as energy cost.
12. Calculate the product and waste costs for each QC
5.3.3.1. KPI calculation
After the MFCA application, the MFCA-Lean methodology next step is the KPI calculation and the
correlation criterion selection to incorporate in the original MFCA calculation model. The present
subsection presents the KPI calculation for QC and for the Total Production System as well as the
criterion selected to compare the KPIs and the correspondent Target Value.
5.3.3.1.1. KPI selection and calculation for QC
Considering the objectives exposed above, different types of evaluation can be selected. The first step
is the calculation of each KPI of each QC. For the QC analysis was selected four cost related and two
operational KPIs. Three of the cost related KPI appraise the contribution of each QC-Section within the
total QC Associated. This evaluation allows the stakeholders to recognise the impact of resources
consumption. Thus, the Material, Energy and System contribution are calculated using
Equations(5.5);(5.6);(5.7) respectively. The fourth KPI cost related presents the contribution of the QC
within the Total Production. This evaluation allows the identification of the QC that most contribute to the
Total Production and is calculated using Equation 5.8.
𝑀𝑎𝑡𝑒𝑟𝑖𝑎𝑙𝑐𝑜𝑛𝑡𝑟𝑏𝑢𝑡𝑖𝑜𝑛𝑄𝐶=
𝑀𝑎𝑡𝑒𝑟𝑖𝑎𝑙 𝑆𝑡𝑜𝑐𝑘 𝑐𝑜𝑠𝑡
𝑄𝐶 𝐴𝑠𝑠𝑜𝑐𝑖𝑎𝑡𝑒𝑑 𝑐𝑜𝑠𝑡(5.5)
𝐸𝑛𝑒𝑟𝑔𝑦𝑐𝑜𝑛𝑡𝑟𝑏𝑢𝑡𝑖𝑜𝑛𝑄𝐶=
𝐸𝑛𝑒𝑟𝑔𝑦 𝑐𝑜𝑠𝑡
𝑄𝐶 𝐴𝑠𝑠𝑜𝑐𝑖𝑎𝑡𝑒𝑑 𝑐𝑜𝑠𝑡(5.6)
𝑆𝑦𝑠𝑡𝑒𝑚𝑐𝑜𝑛𝑡𝑟𝑏𝑢𝑡𝑖𝑜𝑛𝑄𝐶=
𝑆𝑦𝑠𝑡𝑒𝑚 𝑐𝑜𝑠𝑡
𝑄𝐶 𝐴𝑠𝑠𝑜𝑐𝑖𝑎𝑡𝑒𝑑 𝑐𝑜𝑠𝑡(5.7)
𝑄𝐶𝑐𝑜𝑛𝑟𝑖𝑏𝑢𝑡𝑖𝑜𝑇𝑜𝑡𝑎𝑙𝑃𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝐶𝑜𝑠𝑡 =𝑄𝐶 𝐴𝑠𝑠𝑜𝑐𝑖𝑎𝑡𝑒𝑑 𝑐𝑜𝑠𝑡
𝑇𝑜𝑡𝑎𝑙 𝑃𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝐶𝑜𝑠𝑡(5.8)
The two operational KPI selection was explained before in subsection 5.3.2. The setup time is measured
and expressed directly in the output dashboard in hours, and the OEE is obtained using Equation (5.9).
The OEE calculation is based on three factors, the Performance, obtained by Equation (5.10), the
Availability, calculated by Equation (5.11) and Quality, obtained using Equation (5.12).
𝑂𝐸𝐸 = 𝑃𝑒𝑟𝑓𝑜𝑟𝑚𝑎𝑛𝑐𝑒 × 𝐴𝑣𝑎𝑖𝑙𝑎𝑏𝑖𝑙𝑖𝑡𝑦 × 𝑄𝑢𝑎𝑙𝑖𝑡𝑦 (5.9)
𝑃𝑒𝑟𝑓𝑜𝑟𝑚𝑎𝑛𝑐𝑒 =𝐼𝑑𝑒𝑙 𝐶𝑦𝑐𝑙𝑒 𝑇𝑖𝑚𝑒 × 𝑇𝑜𝑡𝑎𝑙 𝐶𝑜𝑢𝑛𝑡
𝑃𝑙𝑎𝑛𝑛𝑒𝑑 𝑃𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝑇𝑖𝑚𝑒 − 𝑆𝑡𝑜𝑝 𝑇𝑖𝑚𝑒(5.10)
𝐴𝑣𝑎𝑖𝑙𝑎𝑏𝑖𝑙𝑖𝑡𝑦 = 1 −𝑆𝑡𝑜𝑝 𝑇𝑖𝑚𝑒
𝑃𝑙𝑎𝑛𝑛𝑒𝑑 𝑃𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝑇𝑖𝑚𝑒(5.11)
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𝑄𝑢𝑎𝑙𝑖𝑡𝑦 =𝐺𝑜𝑜𝑑 𝑜𝑢𝑡𝑝𝑢𝑡 [𝑝𝑎𝑟𝑡𝑠]
𝑇𝑜𝑡𝑎𝑙 𝑝𝑟𝑜𝑑𝑢𝑐𝑒𝑑[𝑝𝑎𝑟𝑡𝑠] (5.12)
The KPIs selected and its calculation for each QC is further used for the evaluation of the production
performance, it allows the stakeholders to recognise if the results obtained met with the expected. The
analysis of the contribution of each QC-section and the OEE is then presented in the dashboard Figure
5-4), “Lean KPIs” and the calculation of the OEE factors is presented in the dashboard (Figure 5-4)
section “Auxiliary data for KPI calculation”.
5.3.3.1.2. KPI selection and calculation for Total
Production System
The cost related KPIs (Material, Energy and System contribution) follows the same approach as the
defined for the QCs. Thus, the cost contribution for the Total Production system is calculated using
Equations (5.13); (5.14); (5.15). Then, were added two KPI only for the Total Production System, the
Material Waste to evaluate the total amount of material lost in physical units and the Defective products
to analyse the amount of parts rejected within the total production volume. The calculation of these KPI
is performed using the Equations (5.16);(5.17) respectively.
𝑀𝑎𝑡𝑒𝑟𝑖𝑎𝑙 𝑐𝑜𝑛𝑡𝑟𝑏𝑢𝑡𝑖𝑜𝑛𝐹𝑃=
𝑀𝑎𝑡𝑒𝑟𝑖𝑎𝑙 𝐼𝑛𝑝𝑢𝑡 𝑐𝑜𝑠𝑡
𝑇𝑜𝑡𝑎𝑙 𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝑐𝑜𝑠𝑡 (5.13)
𝐸𝑛𝑒𝑟𝑔𝑦𝑐𝑜𝑛𝑡𝑟𝑏𝑢𝑡𝑖𝑜𝑛𝐹𝑃=
𝐸𝑛𝑒𝑟𝑔𝑦 𝑐𝑜𝑠𝑡
𝑇𝑜𝑡𝑎𝑙 𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝑐𝑜𝑠𝑡(5.14)
𝑆𝑦𝑠𝑡𝑒𝑚𝑐𝑜𝑛𝑡𝑟𝑏𝑢𝑡𝑖𝑜𝑛𝐹𝑃=
𝑆𝑦𝑠𝑡𝑒𝑚 𝑐𝑜𝑠𝑡
𝑇𝑜𝑡𝑎𝑙 𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝐶𝑜𝑠𝑡(5.15)
𝑀𝑎𝑡𝑒𝑟𝑖𝑎𝑙 𝑊𝑎𝑠𝑡𝑒 =𝑀𝑎𝑡𝑒𝑟𝑖𝑎𝑙 𝑊𝑎𝑠𝑡𝑒
𝑀𝑎𝑡𝑒𝑟𝑖𝑎𝑙 𝐼𝑛𝑝𝑢𝑡(5.16)
𝐷𝑒𝑓𝑒𝑐𝑡𝑖𝑣𝑒 𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑠 =𝐷𝑒𝑓𝑒𝑐𝑡𝑖𝑣𝑒 𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑠
𝑇𝑜𝑡𝑎𝑙 𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 (5.17)
5.3.3.1.3. KPIs vs Target Values
The present study has four Target Values defined by the managers presented in subsection 5.3.2. To
evaluate the production performance by the correlation between the system’s KPIs and the
correspondent Target Value two evaluation criteria were defined based on the KPI nature. The direct
ratio between the Target Value and the KPI was selected to appraise the variation of the Total Production
Time, using Equation (5.18), and the Setup time, by Equation (5.19). The correlation criterion to calculate
the discrepancy of the OEE and the defective products was the difference between the values
(percentage points), using Equation (5.20) and Equation (5.21). Since the OEE and the Defective parts
are a percentage number, this criterion makes the discrepancy more perceptible.
𝑇𝑜𝑡𝑎𝑙 𝑃𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝑇𝑖𝑚𝑒𝑑𝑒𝑣𝑖𝑎𝑡𝑖𝑜𝑛 =𝑇𝑜𝑡𝑎𝑙 𝑃𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝑡𝑖𝑚𝑒𝑇𝑉
𝑇𝑜𝑡𝑎𝑙 𝑃𝑟𝑜𝑑𝑢𝑐𝑡𝑖𝑜𝑛 𝑡𝑖𝑚𝑒𝑅𝑒𝑎𝑙
(5.18)
64
𝑆𝑒𝑡𝑢𝑝 𝑡𝑖𝑚𝑒𝑑𝑒𝑣𝑖𝑎𝑡𝑖𝑜𝑛 =𝑆𝑒𝑡𝑢𝑝 𝑡𝑖𝑚𝑒𝑇𝑉
𝑆𝑒𝑡𝑢𝑝 𝑡𝑖𝑚𝑒𝑅𝑒𝑎𝑙
(5.19)
𝐷𝑒𝑓𝑒𝑐𝑡𝑖𝑣𝑒 𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑠𝑑𝑒𝑣𝑖𝑎𝑡𝑖𝑜𝑛 = 𝐷𝑒𝑓𝑒𝑐𝑡𝑖𝑣𝑒 𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑠𝑅𝑒𝑎𝑙 − 𝐷𝑒𝑓𝑒𝑐𝑡𝑖𝑣𝑒 𝑝𝑟𝑜𝑑𝑢𝑐𝑡𝑠𝑇𝑉 (5.20)
𝑂𝐸𝐸𝑑𝑒𝑣𝑖𝑎𝑡𝑖𝑜𝑛 = 𝑂𝐸𝐸𝑅𝑒𝑎𝑙 − 𝑂𝐸𝐸𝑇𝑉 (5.21)
The information presented above as well as the necessary outputs to calculate the Lean related KPIs is
organised in each QC column as previously presented in subsection 5.2.4 - Figure 5-4
5.3.4. Critical QC and KPIs identification
The analysis of results and identification of critical QC and KPIs is performed based on the methodology
dashboard (Figure 5-4). It describes, not only, the costs per QC (input; output, product and waste) and
per QC-section as the original MFCA, but also, presents the actual performance of the process by the
KPIs presentation. Moreover, this MFCA-Lean dashboard presents also the discrepancy between the
KPI and the Target Value. Allowing the user to evaluate if the pre-defined plan was being fulfilled as
planned. These properties make the MFCA-Lean dashboard more extensive than the original MFCA
flow map and more detailed and objective than Lean analysis.
65
From the analysis of the obtained dashboards, it is possible to find the critical KPIs which allow the
identification of improvement opportunities. To perform that evaluation the analysis of different
categories proposed in section 5.2.5 is followed. For this specific case-study the KPI that presents the
highest distance to the TV were considered more appropriate for the analysis per QC; QC which has
Product Flow
Material Waste Flow
Figure 5-6 – Methodology dashboard for the production system per QC
Figure 5-7 Methodology general dashboard of Total Production System
66
the highest contribution to the Total Production cost and also the KPI which influences this contribution.
For the analysis of the TPS was also considered that an evaluation of the QC that most contributes to
the Total Production Cost was appropriate to assess the critical sub-section. Once performed a visual
analysis of the dashboard obtained, the results were compiled in a matrix for further analysis. This matrix
is organised considering the KPI, the associated cost of each KPI and the criticality level which in turns
evaluated using a colour system. The system colour is divided in two, the red highlight the most critical
value in terms of cost and percentage, and the yellow the second more critical. For each selection
category, the matrix presents the two worse performances, showing the two more critical parameters.
(Table 5-10)
Table 5-10 Identification of critical QC and KPI (per QC and TPS)
The matrix (Table 5-10) is an important MFCA-Lean methodology output: it allows some important
analyses, namely the identification of the QC and KPI critical. The study of this results is dependent on
the analysis and objective of the MFCA-Lean methodology user. In this case, the analysis performed by
the production system in the study is presented per QC and for the Total Production.
Per QC
• The Total Production Time is the KPI with the highest deviation to the respective TV. This
corresponds to 12 perceptual points more than the expected value which represents more than
74.01€ of the production costs;
• The QC with the highest associated cost is the Injection Machine. This QC represents 54% of
the Total Processes Cost that corresponds to almost 116€. It is followed by the QC -Packaging
that represents 33 perceptual points.
• The KPI that contributes more to the QC- Injection Machine is the Material Waste which
represents 37.58 perceptual points of the production which is translated in 237.58€.
For Total Production System:
• The KPI that has the highest contribution to the Production system cost is the Material Input
representing 72.4 perceptual points of the total costs, i.e. 515.37€.
67
From the evaluation of the Total Production System is possible to assess that this value comes in part
from the material wasted throughout the production system, 37.58%. However, 30.21% of that value
corresponds to a manufacturing condition and is mandatory for the manufacturing process.
Consequently, the percentage of material losses, which are a consequence of the runner production to
produce only the good parts, is considered as a material loss for the MFCA application but is a necessary
loss for the process. If the runner’s material were considered as required input, the amount of wasted
material would decrease to 7.37%. The meticulous analysis of the material’s waste nature shows that
within this 7.37%:
• 0.08% is related to the material replacement due to changes in production order;
• 2.41% represents discharges of material after setup;
• 4.88% comes from the production of defective parts and parts destroyed due to the destructive
quality control test.
To evaluate the improvement opportunity related to the material consumed, the analysis of the financial
impact of replacing the cold runner system by one with hot runners is suggested (used in production
system exposed in section 4). However, this evaluation is not part of the dissertation objectives, for that
reason the System cost is recognised as the critical KPI for this subject.
The re-evaluation of the Total Production System results identifies as critical the System contribution for
the entire production costs. Table 5-11 presents the input of each QC-system per QC within the System
cost of the Total Production System allowing the recognition of the QC that contributes more to the total
System costs.
Table 5-11 The contribution of each QC-System within the Total System Cost
System Cost %QC within Total
System Cost
Raw Material Area 3,73 € 2%
Hopper Dryer 5,53 € 3%
Injection Machine 100,40 € 56%
Packaging 53,14 € 30%
Quality Control 14,40 € 8%
Final Product Warehouse 3,48 € 2%
Waste Management - 2,74 € -2%
Total 177.95 € 100%
The analysis of Table 5-11 shows that the critical QC is the Injection Machine which represents 56% of
the total system cost, i.e. 100,40 €, followed by the QC- Packaging that is 30% of the total system costs.
Attempting that the QC Injection Machine and Packaging are also pointed as critical once are the QCs
with the highest associated cost, Table 5-10. Consequently, a root cause analysis should be performed
to these two QCs and the most critical must be selected for further analysis.
68
The Total Production Time, which is pointed as critical in Table 5-10 it is, not only, dependent on the
manufacturing time but also takes into account the Setup time (also pointed as critical KPI). For that
reason, it may be relevant the further analysis.
5.3.5. Lean application tools
The present section aims to reduce the KPIs which were considered as critical in the previous analysis
throughout the application of Lean tools. Considering the previous critical KPI and QC identification, a
different analyses were performed to each KPI considered critical to access the Root-Causes and then
possible solutions. This subsection is organised as follows. Firstly, a root-cause analysis is performed
to access the reason behind the critical KPI. Then, the most critical or the KPI that has the highest
influence on the Production System Cost is selected to further analysis. Finally, the Problem-Solving
solutions were applied and the MFCA-Lean methodology results confirmed.
5.3.5.1. Lean Root-Cause tools application
In the previous section was suggested that the QC- Injection Machine and the QC-Packaging were the
QC that has the highest contribution for the QC-System of the Total Production System. Thus, a root-
cause analysis was performed to these two QC using the 5Whys and 5Ws diagnostic tools.
Table 5-12 presents a detailed analysis of the system costs distribution for the critical QCs to support
the root-cause analysis presented above.
Table 5-12 Comparison value between System cost of Packaging and Injection Machine processes.
QC-Packaging QC- Injection Machine
Labour (total) 52,27 € 51,62 €
Responsible 2,70 € 9,26 €
Leader - € 16,30 €
Employee 49,56 € 2,66 €
Leader supporter - € 23,40 €
Space (total) 0,06 € 1,70 €
Equipment (total) 0,82 € 48,72 €
Total Process’s System Cost 53,14€ 102,04€
69
For QC-Injection Machine: Combined 5Whys and 5Ws for root-cause analysis Figure 5-8.
Figure 5-8 Root-cause analysis to the QC-Injection Machine
From the 5Whys analysis (Figure 5-8) is possible to conclude that the root-cause of the QC-System high
value in the Injection Machine is due firstly the equipment and labours involved in the process. However,
when the root-cause is analysed in detail is accessible that the Equipment value is a consequence of
the machine depreciation. However, the Labour cost is divided in Project manager (18%), Team Leader
(31.6%), Employee (5.1%) and Leader supporter (45.3%) (Table 5-12). As explained in chapter 3 the
Leader supporter main tasks are related to setup activity and the raw material supply. Hence, the root-
cause continuous to understand the reason behind that. Thus, the specialisation level required to
perform the setup activity is directly related to his hour cost. Moreover, the setup activity is also pointed
as the second more critical concerning about the KPI Target Value discrepancy (Table 5-10). Based on
the previous description, the setup is considered the root-cause of the QC-Injection Machine contribution
for the Total System Cost.
Why?
Root-Cause
Because of the Equipment and the Labours involved in this QC.
Why? Because is the QC with the highest resources consumption
The QC-Injection Machine is the 1st QC that contributes more for the TSC Why?
Why?
Because Injection Machine and
the mould are equipment’s with
expensive depreciations
Because this QC involves four
different levels of employees
Root-Cause
Which employee has the
highest contribution for
the labour’s cost??
Leader Supporter
Why?
Because he is a specialized
What does he do?
He performs the Setup Root-Cause
Statement
70
For QC-Packaging: 5Whys Root-cause analysis for System cost in QC-Packaging, Figure 5-9.
From the 5Whys analysis is possible to access that the contribution value which comes from the QC-
Packaging is related to the time spent by the employee to perform that task. The packaging activity has
specific requirements from the quality department, and the operator needs to perform these tasks
following the procedure. Since QC-Packaging is dependent on the quality requirements and that the
most critical QC has an operational cause. The QC-Injection Machine more specifically the Setup can
be improved by the application of a specific Lean tool this parameter is selected for further analysis.
For the Total Production Time:
The last critical KPI to be evaluated is the Total Production Time. To appraise the root-causes of this KPI
a cause analysis based on 5Whys is performed and presented in Figure 5-10. The first two causes are
related to the mould condition, and the third is related to Setup time. The setup time influences the Total
System time since this last is dependent on the manufacturing time but also takes into account the Setup
time which can be improved by the application of problem-solving solutions.
Labour is the sub-section of the QC-System in the QC-Packaging with the highest value. cost.
Why?
Because the packaging phase is the phase that the labour spends most of the time.
Why?
Because the product is packaged in concrete boxes that need to be tagged and this
work is performed by the employee.
Root-Cause
The QC-Packaging is the 2nd QC that contributes more for the Total System Cost Why?
Figure 5-9 Root-cause analysis to the QC-Packaging
71
Figure 5-10 Root-cause analysis to the Total Production Time
Based on the previous analysis is possible to conclude that a reduction of the setup time will reduce its
costs contribution leading, not only, to a positive result in the Labour component of the QC- System
within the injection machine, but also, to a positive impact in the Total Production Time. Thus, if the Total
Production Time is reduced, the cost contribution of the space and equipment would also be reduced.
Regarding these assumptions, the Setup time is selected as a parameter to be analysed carefully as an
improvement opportunity point.
As a primarily conclusion, the MFCA-Lean methodology allows the identification of the critical QC based
on the company's goals. Moreover, without the root-cause analysis performed through the application
of Lean tools, the root-causes of this production issues were not directly identified with the MFCA
application to the production system. Figure 5-11 presents a summary information analysis of the
present subsection to provide a clear idea about the influences
Root-Cause
Root-Cause
Why?
Why?
Production system worked
with a cycle time higher
than the expected
Overproduction: +2004
than the expected
Why?
Setup Time
Because the mould was
achieving the maintenance
time. Thus, some parts were
produced with defects.
Adding, considering the real
cycle time, 2.49 hours and
considering the ideal cycle
time 2.44 hours
Why?
Because it takes more 1.72
hours than the expected.
Why?
Total Production Time is higher than the expected
Why?
Because the mould was
achieving the maintenance
time. Thus, some production
parameters were adapted to
guarantee the production of
the components. These
adjusts are translated in 0.8
hours of additional
production time
Root-Cause
Statement
72
Figure 5-11 Cause analysis of the critical value of the total system cost
5.3.5.2. Lean problem-solving solutions application
The present section aims to reduce the most critical KPI pointed in the previous subsection throughout
the application of Lean problem-solving tools. Based on the root-cause information of the critical KPIs
(Setup time) a problem-solving solution was applied, and its improvement results analysed.
Firstly, a Gemba Walk was performed focused in the QC- Injection Machine [where the Setup occurs].
Then the Setup process was observed and some wastes of the time were identified. Based on that
identification, two different tools were applied, the 5S and SMED. The explanation of both tools is
presented in – subsection 5.1.
During the Setup observation, the following issues were identified:
i. The specific lubricant was not separated from the others and the employee wastes time looking
for it.
ii. The cleaning material was not close to the work area and the employee wastes time measuring
and transporting it.
iii. The new mould was far from the Machine. Consequently, the employee wasted time to look for
it into the mould warehouse.
iv. The assembling and disassembling tools were not organised and identified for the change of
the specific mould.
v. The new product folder warehouse is far from this machine and the employee wasted time.
Which parameters within the critical QC section of
the critical QC are influenced by the Total
Production Time? And how?
Space and Equipment cost due to the cost
allocation of these parameters is performed based
on the Total Production Time
Which parameters are analysed in
this section?
Labour Space Equipment
There is any unhoped value? Setup time and cost
Critical QC-Section within TPS: Total System Cost
QC that represents the highest contribution in the
QC-section above: QC -Injection Machine
Which parameter is influenced by Setup time?
Total Production Time
73
vi. The Quality control team was not expecting the approval call, and they take longer to approve
the product originating a waste of time and possibly of material since the production was already
started.
Considering these issues, a 5S tool was applied focused in the tools organisation and the preparation
of these accessories to obtain an organised and easy to access area. This tool application aims to
reduce the issues i, ii and iv listed above.
Firstly, the tools and consumables (lubricant and operating materials) were divided into the required
ones for the mould change and the ones not needed. Then, the necessary consumables were organised
on the top of the tool cart close to the Machine and organised having in consideration the sequence of
requirements. This sequence was selected based on the employee experience and the sequence of
events observed. Then, the additional equipment and materials were stored in the tool cart to promote
a clean work area.
In parallel with the previous tool, the SMED tool was also suggested to convert internal steps, into
external steps of the process. This tool’s application goal is to reduce i-v issues presented above when
combined with the previously suggested tool. The activities selected to transform into external activities,
i.e., the ones that should be performed before the mould change starts, includes the following:
1. The organisation tools, consequence of the 5S application, was performed before the end of
the previous production;
2. Prepare the new mould and storage the mould cart close to the machine;
3. Bring the overhead crane close to the injection machine;
4. Prepare the cleaning material and store it close to the tool cart;
5. Bring the new mould folder and the robot accessories to the support machine table;
6. Notify the quality control team that the setup is going to happen and they will be called in
approximately 1hr30min.
The results presented in Table 5-13 shows that the Lean tools allowed a setup reduction of 51%. After
the application of the improvement solutions, the MFCA was reapplied to check the enhancement results
based on the financial implications. Table 5-14 presents the global results of the manufacturing system
regarding the costs and the reduction after the application of the improvements.
Table 5-13 Setup time after lean tools application
Before tools
application
Expected after SMED and
5S application
Real after SMED and
5S application
Setup time 3hr 13 min 1hr 25 min 1hr 35 min
Setup reduction -56% -51%
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Table 5-14 Final Results after Lean application tools
TPS Improvement Results After problem-solving tools
Per production KPI of TPS Units
Energy - 0,53 € - 0,02% - 6,36 Kw
System - 16,15 € - 1,72%
Product - 10,98 € Kg
Waste - 5,69 € Kg
Total Production - 16,68 € - 2% -1,59 h
Total Production time -3%
Through the analysis of the Total System Results obtained after the MFCA-Lean methodology first
application (Table 5-14) is possible to conclude that the improvements applied allowed not only, the Total
System Cost and consequently the Total Production Cost reduction in 16.15€ (-1.72%) and 16.68€ (-
2%) respectively but also, the decrease of the energy consumed. It also led to the improvement of the
OEE in 5.4%.
Thereafter a the MFCA-Lean Methodology should be re-applied to promote a continuous improvement
cycle. A revaluation of the “new” critical factors and the reapplication of the entire methodology should
be performed and in case of a lack of discrepancy between the TV and KPI a parameter's reformulation
is suggested.
5.4. Methodology application conclusions
The application of the novel MFCA-Lean methodology allows (i) the identification of the real product
manufacturing state, (ii) the cost distribution per process, (iii) the identification of improvement
opportunities (iv) the diagnosis and problem-solving analysis and solutions to overcome the production
issues and (v) the update of the production performance using the data obtained through the application
of the problem-solving solutions.
The MFCA-Lean methodology should encourage the company’s managers to re-evaluate their strategy
through the production system performance, and support their decision-making promoting a continuous
improvement cycle to tackle the market pressure.
Furthermore, during the application of this integration methodology to a case study, the critical aspects
and the improvement solution were identified, as well as applied. Then, the results were evaluated, and
its study presents a reduction in the Total Production Costs considering the type of company and
production system. The application of MFCA-Lean methodology allows the comprehension of the 3% of
reduction in the total production time led to a cost decrease of 2% in a two days production system.
Since the mould's industry is characterised by being a non-stop industry a 3% time reduction can be
translated a great impact on the company’s economy and availability.
75
6. Conclusions
The present dissertation had two main objectives. The first one, related to the validation of the
application of MFCA methodology to a production system and the assessment of its benefits when
applied as a diagnostic tool. To assess that information, during the MFCA analysis a detailed observation
was performed. Once understood the main advantages and limitations of its application concerning
production flows, aims at the development of a methodology which could integrate MFCA method with
Lean tools. To accomplish these goals, a production unit which follows a MTS strategy was used as a
first case-study, then the MFCA-Lean methodology was developed and applied to a production unit
which follows a MTO strategy. This last was used as a second case-study to validate the MFCA-Lean
methodology.
The application of the MFCA analysis through the direct application of the ISO standard 14051 [3] to a
production unit supported the company to understand the magnitude of the resources used and flows
in terms of product and waste costs. The results obtained through MFCA application reveals that the
real waste percentage was three times higher than the company expected
Hence, MFCA proved to be an appropriate tool of diagnostic in terms of monetary values. i.e, the MFCA
is an effective tool to determine the resources uses and transformed as a product or loss in terms of
monetary performance. It presents the real production cost of the production system based on an
extensive data collected and allow the analyser to directly identify some obvious inefficiencies.
Moreover, it could be a useful diagnostic tool to recognise some production inefficiencies during the
analysis and data gathering period only if it is supported by a simultaneous careful observation. As a
primary conclusion, MFCA analysis allow the accounting of all material and resources wasted based on
an extensive data and system characterization but is not prepared to take care with inefficiencies from
the manufacturing system point of view – as Lean tools.
MFCA-Lean methodology appears to overcome the MFCA limitations presented. From the observation
performed concerning MFCA and Lean tools complementarities, a literature review of both was
performed to support the MFCA and Lean tools integration possibility. Then, the methodology was
developed and successfully applied to an injection moulding production system which follows a MTO
strategy.
From the application results it was possible to conclude that the MFCA-Lean methodology allows, not
only, the understanding of the costs incurred in its production systems and its flow, but also highlights
the critical KPI through its comparison with the aimed target values. In addition, it provides specific Lean
tools to evaluate the root-cause of the problem and uses problem-solving tools to solve the existent
issues. Moreover, after the application of the proposed solutions the methodology allows the
confirmation of results in monetary units due to the performance of the improvement activities,
consequently the second aims of this dissertation is achieved.
76
As final conclusions, the MFCA method and Lean tools can be integrated. This integration based on
steps procedure allows the accomplishment of aimed results directly aligned with company’s objective
and scope. MFCA-Lean methodology is able to present the real state of the production system in
monetary units for manager’s encouragement to re-evaluate their strategy and provide tools to recognise
root-causes, support and improve employees’ activities guiding efficiently their work. This methodology
should be implemented as a continuous improvement cycle so the production process moves closer to
the ideal optimized process.
7. Future Work
In this Chapter, a few suggestions for future work in the dissertation field are presented.
Firstly, is suggested that the development of a methodology or at least a guideline to model the energy
flows independently of the material flows. The allocation of the energy under the material flow usually
neglects several types of energy waste as, vibrations or heat transfer. The efficient identification of
energy efficiencies can improve the environmental performance of a company, as well as deeper
understanding of the environmental and economic performance
Thus, is suggested the application of the MFCA-Lean methodology developed in this work in different
manufacturing systems. Since it was only applied once and to an injection moulding production process,
the scope of its applicability should be extended to support the methodology validation.
77
8. References
[1] K. Kokubu and H. Tachikawa, “Material Flow Cost Accounting: Significance and Practical
Approach?,” in Handbook of Sustainable Engineering, Dordrecht: Springer Netherlands, 2013,
pp. 351–369.
[2] R. Sygulla, a Bierer, and U. Götze, “Material Flow Cost Accounting–Proposals for Improving the
Evaluation of Monetary Effects of Resource Saving Process Designs,” 44th CIRP Int. Conf.
Manuf. Syst., no. June, pp. 1–3, 2011.
[3] DIN EN ISO (14051:2011), “Environmental Management – Material Flow Cost Accounting-
General Framework (ISO 14051),” 2011.
[4] A. Schmidt, U. Götze, and R. Sygulla, “Extending the scope of Material Flow Cost Accounting -
Methodical refinements and use case,” J. Clean. Prod., vol. 108, pp. 1320–1332, 2015.
[5] S. J. Spear, “Learning to Lead at Toyota Learning to Lead at Toyota.”
[6] B. Wagner, “A report on the origins of Material Flow Cost Accounting (MFCA) research activities,”
J. Clean. Prod., vol. 108, pp. 1255–1261, 2015.
[7] K. L. Christ and R. L. Burritt, “Material flow cost accounting: a review and agenda for future
research,” J. Clean. Prod., vol. 108, pp. 1378–1389, 2015.
[8] U. Götze, A. Hertel, A. Schmidt, and E. Päßler, “Technology and Manufacturing Process
Selection,” pp. 281–296, 2014.
[9] R. Sygulla, U. Götze, and A. Bierer, “Material Flow Cost Accounting: A Tool for Designing
Economically and Ecologically Sustainable Production Processes,” Technology and
Manufacturing Process Selection, pp. 281–296, 2014.
[10] E. Guenther, C. Jasch, M. Schmidt, B. Wagner, and P. Ilg, “Material flow cost accounting -
Looking back and ahead,” J. Clean. Prod., vol. 108, pp. 1249–1254, 2015.
[11] M. K. Devaraju, M. Sathish, and I. Honma, “Handbook of Sustainable Engineering,” Handb.
Sustain. Eng., pp. 1149–1173, 2013.
[12] M. Schmidt and M. Nakajima, “Material Flow Cost Accounting as an Approach to Improve
Resource Efficiency in Manufacturing Companies,” Resources, vol. 2, no. 3, pp. 358–369, 2013.
[13] A. Bierer and U. Götze, “Energy Cost Accounting: Conventional and Flow-oriented Approaches,”
J. Compet., vol. 4, no. 2, pp. 128–144, 2012.
[14] K. L. Christ and R. L. Burritt, “ISO 14051: A new era for MFCA implementation and research,”
Rev. Contab., vol. 19, no. 1, pp. 1–9, 2016.
[15] Environmental Industries Office, Environmental Policy Division, Industrial Science and
Technology Policy and Environmental Bureau Ministry of Economy, and Trade and Industry
Japan, “Guide for Material Flow Cost Accounting,” no. March, pp. 1–48, 2007.
78
[16] M. Nakajima, “by Material Flow Cost Accounting ( MFCA ) the Nikkei Ecology of Sustainable
Management â€TM ( Nikkei,” vol. 8, no. 8, pp. 1–22, 2006.
[17] Ministry of Economy, Trade and Industry Japan (METI), “Material Flow Cost Accounting - MFCA
Case Examples,” 2011.
[18] Lean-Manufacturing-Japan, “MTO (Make To Order) | Lean Manufacturing.” [Online]. Available:
http://www.lean-manufacturing-japan.com/scm-terminology/mto-make-to-order.html. [Accessed:
05-May-2017].
[19] Lean-Manufacturing-Japan, “MTS (Make to Stock) | Lean Manufacturing.” [Online]. Available:
http://www.lean-manufacturing-japan.com/scm-terminology/mts-make-to-stock.html. [Accessed:
05-May-2017].
[20] M. R. Kamal, Injection Molding: Introduction and General Background, First Edit. Carl Hanser
Verlag GmbH & Co. KG, 2009.
[21] D. M. Bryce, Plastic injection molding : material selection and product design fundamentals.
Society of Manufacturing Engineers, 1997.
[22] T. Sakai and K. Kikugawa, Part II: Injection Molding Machinery and Systems: Injection Molding
Machines, Tools, and Processes, First Edit. Carl Hanser Verlag GmbH & Co. KG, 2009.
[23] D. V. Rosato, D. V. Rosato, and M. G. Rosato, Injection Molding Handbook. Springer US, 2000.
[24] “Mold Making & Plastic Injection – Page 2 – Blog of SFMA GROUP.” [Online]. Available:
https://sfmagroup.wordpress.com/category/mold-making-plastic-injection/page/2/. [Accessed:
19-Apr-2017].
[25] B. Saha, W. Q. Toh, E. Liu, S. B. Tor, D. E. Hardt, and J. Lee, “A review on the importance of
surface coating of micro/nano-mold in micro/nano-molding processes,” J. Micromechanics
Microengineering, vol. 26, no. 1, p. 40, 2016.
[26] NIIR Board of Consultants and Engineers, THE COMPLETE TECHNOLOGY BOOK ON
PLASTIC EXTRUSION, MOULDING AND MOULD DESIGNS, 1st ed. 2006.
[27] P. V. Vasconcelos, F. J. Lino, and R. J. L. Neto, “Estudo de injecção de termoplásticos em moldes
produzidos em compósitos de base epoxídica de alta temperatura,” Paginas.Fe.Up.Pt, 2003.
[28] D. E. Dimla, M. Camilotto, and F. Miani, “Design and optimisation of conformal cooling channels
in injection moulding tools,” J. Mater. Process. Technol., vol. 164–165, pp. 1294–1300, 2005.
[29] “Understand Cold Runner and Hot Runner Systems for Plastic Injection Molding.” [Online].
Available: http://info.crescentind.com/blog/bid/70016/Understand-Cold-Runner-and-Hot-
Runner-Systems-for-Plastic-Injection-Molding. [Accessed: 16-May-2017].
[30] “Injection Molding Process, Defects, Plastic.” [Online]. Available:
http://www.custompartnet.com/wu/InjectionMolding. [Accessed: 15-May-2017].
[31] “Hot Runner vs. Cold Runner Systems: Which Should You Use?” [Online]. Available:
79
https://www.simtec-silicone.com/injection-molding-feeding-systems-hot-runner-molds-vs-cold-
runner-molds/. [Accessed: 15-May-2017].
[32] A. Schmidt, U. Götze, and R. Sygulla, “Extending the scope of Material Flow Cost Accounting –
methodical refinements and use case,” J. Clean. Prod., vol. 108, pp. 1320–1332, 2015.
[33] R. Basu, Implementing Six Sigma and Lean: A practical guide to tools and techniques. 2008.
[34] T. L. Doolen and E. M. Van Aken, “Kaizen events and organizational performance: a field study,”
Int. J. Product. Perform. Manag., vol. 29, no. 5, pp. 494–519, 2009.
[35] D. K. Sobek and C. Jimmerson, “A3 Reports: Tool for process improvement,” IIE Annu. Conf.
Proceedings;, vol. m, pp. 1–6, 2004.
[36] M. Korenko, V. Kročko, M. Ţitňák, D. Földešiová, M. Adamik, and Š. Álló, “Application 8D Method
for Problems Solving,” 2008.
[37] Q-1 International - Discover the value, “8D | Eight Disciplines of Problem Solving | Quality-One.”
[Online]. Available: http://quality-one.com/8d/#what. [Accessed: 29-Aug-2017].
[38] S. Tyagi, A. Choudhary, X. Cai, and K. Yang, “Value stream mapping to reduce the lead-time of
a product development process,” Int. J. Prod. Econ., vol. 160, pp. 202–212, 2015.
[39] R. Basu and R. Basu, “Chapter 6 – Tools for analysis,” in Implementing Six Sigma and Lean,
2008, pp. 89–111.
[40] ValactionContinuousImprovment, “5W1H | Who, What, When, Where, Why, and How.” [Online].
Available: http://www.velaction.com/5w1h/. [Accessed: 05-Aug-2017].
[41] CreatingMinds, “The Kipling method (5W1H).” [Online]. Available:
http://creatingminds.org/tools/kipling.htm. [Accessed: 05-Aug-2017].
[42] S. Republic, “AN EASY WAY TO DETECT PROBLEM ´ S ROOT CAUSE : IS – IS NOT
ANALYSIS Yulia ŠURINOVÁ , Iveta PAULOVÁ,” pp. 18–21.
[43] R. Basu and R. Basu, “Chapter 5 – Tools for measurement,” in Implementing Six Sigma and
Lean, 2008, pp. 64–88.
[44] Adaptive Business Management Systems Ltd, “Yamazumi charts | Adaptive BMS.” [Online].
Available: https://www.adaptivebms.com/Introduction_to_Yamazumi_charts/. [Accessed: 29-
Aug-2017].
[45] R. Basu and R. Basu, “Chapter 7 – Tools for improvement,” in Implementing Six Sigma and Lean,
2008, pp. 112–132.
[46] R. Basu and R. Basu, “Chapter 10 – Qualitative techniques,” in Implementing Six Sigma and
Lean, 2008, pp. 195–240.
[47] KAIZEN INSTITUTE, “Mizumashi.” [Online]. Available:
http://pt2013.kaizen.com/formacao/glossario.html?no_cache=1&tx_contagged%5Bsource%5D
=default&tx_contagged%5Buid%5D=2863&cHash=630373e06873dfab8dc1dce5fd6a2507.
80
[Accessed: 02-Jun-2017].
I
9. Annexes
Annex A - Equipment identification
The equipment used for the manufacturing process through an injection moulding system are presented
in the following table.
Table A-1 – Machines for production and its description
Machine involved in the production Description
The first picture represents an injection machine,
this machines is used by the company to create
the plastic components. Those are working
according with the schedule and the needs.
Once the injection process works with specific
temperature becomes necessary the presence of
a chiller (second picture), this machine is
responsible for cooling the water that refrigerates
the necessary components
These component is a mould one of the most
important and expensive components of the
process. It has two important functions, moulding
the melted plastic and solidifying the moulded
product. Each mould is created to produce a high
quantity of parts with a high level of quality.
The first component is a hopper dryer, these
machine is responsible for drying the material,
when the specifications require it. The second
one is a vacuum pump, in this system the vacuum
pump is responsible for the material distribution.
The plastic shredder machine is responsible for
shredding the material. This equipment is used
for recycling the material
II
The transport equipment is responsible for carrying feedstock and auxiliary materials supply, storage
and product truck loading. All this equipment are managed and used by the logistic department. By its
understanding the allocation time of the employee who managed it and the equipment cost in the correct
quantity centre was possible. Thus, its description is presented in the following table
Table A-2- Machines involved in product transportation and its description
Machine involved in product transport Description
The first picture represents a stacker forklift,
these device is used to move the material or the
product in the warehouse, and it’s mainly used to
storage the product in shelves. The second one
is an electric forklift and it’s used to move heavy
loads, it’s mainly used to transport the raw
material from the outside to the inside of the
warehouse ɪ. Both devices requires a specialized
employee to handle it.
These component is a handle forklift, is similar to
the presented before, the difference is in these
case the employee needs to be in a vertical
position, and these equipment is only used for the
transportation of the material, inside the
warehouse.
The last equipment used is the vertical palletizer,
in this case, the pallet of final product is inserted
on the base, and this base had a rotational
movement and at the same time a film roll moves
vertically. Following this movement, the pallet is
totally palletized and in the end is ready to be
storage.
III
Annex B - Company’s Teams and departments
The description of the teams and departments involved in the support to the manufacturing process are
explained in the following table. These departments operate independently, however they all have a
fundamental contribution to a proper system conduct. The clear knowledge of the teams and
departments and, therefore, a clear understanding of the process stages was essential for the definition
of the Quantity Centres (key task of the MFCA method)
Table B-9-1-Teams and departments involved in the manufacturing process
Teams/Departments Description
Management Department The management department complains the financial and
business section.
Engineering Department
The engineering department is responsible for testing, adapt and
validate the possibility of new products being produce in the
company.
Logistic Department
The logistic department is responsible for the warehouse
management and must guarantee the flow of material in the
productive process. It is also responsible, for shipping the final
product, the stock management of material and the raw material
supply, as well as the production forecast and the schedule.
Quality Department
The quality department assures the high level of the product
quality as well as the client satisfaction and the accomplishment
of the ISO norms, dimensional and apparent aspect of the product.
Maintenance Team
The maintenance team is responsible for maintain the correct
functioning of all the equipment (machines, conveyor belts…),
through the last minute problem solving.
Production
The production team is responsible for regulate the injection
machine parameters to obtain a quality product, for guarantee the
correct material flow. It also should assure the correct number of
manufactured products, according with the scheduled plan
avoiding the overproduction as well as the underproduction. It is
also responsible for a type of preventive maintenance (cleaning
the mould once a shift and the machines once a week).
IV
Annex C - Operating materials – QC and utilisation
All the operating materials presented in this Annex are used for the production system of both Parts,
and is divided per QC where they are used.
Table C-1- Operating materials
QC Operating material Frequency
Injection
Machine
Alcohol 96% Shiftly maintenance
Cleaning Cloths all the maintenances
Tribol 4020/220-2 weekly and monthly
maintenance
Petraqua and Salt monthly maintenance
Tribol 800/460; 800/220 ; 3020/100 annual maintenance
Lubricant mass annual maintenance
Packaging
Boxes 1 per 2500 parts
Plastic bags 1 per 2500 parts
Adhesive tape 1 per box
Tags 1 per box
Pallets 1 per 48 boxes of Part1
1 per 16 boxes of Part2
Foam 1 per Pallet
Final Product Palletizing film 1 portion per pallet
V
Annex D - Employees’ time distribution per QC
This annex presents the time distribution per type of employee for both case studies.
Case-study of the MTS production strategy:
Dedicated employees : Project Leader, Team Leader and employee
Table D-1 – MTS production – Employees time distribution
Component QC Project Leader
Allocation Team Leader
Allocation Employee Allocation
Product Raw Material Area 2,0% 25,0% 5,0%
Hopper Dryer 1,0%
Part 1 Injection Machine 30,0% 35,0% 5,0%
Part 1 Lid QC 15,0% 10,0%
Part 1 Lid Packaging 1,0% 35,0%
Part 2 Cup IM 30,0% 40,0% 5,0%
Part 2 Cup QC 15,0% 10,0%
Part 2 Cup Packaging 1,0% 30,0%
Part 1 Lid - Rejected 2,5%
Part 2 Cup - Rejected 2,5%
Non-dedicated employees: Raw material area Employee, Employee responsible for grinding off-
specified parts, Final Product Warehouse employee.
The non-dedicated employee time distribution is based on the time spend per each employee do
performed their tasks within theirs work time.
Table D-2 – MTS production – non-dedicated Employees time distribution
Component QC Raw material
area Employee
Employee responsible for
grinding off-specified parts
Final Product Warehouse employee
Product Raw Material Area 2,0%
Hopper Dryer
Part 1 Injection Machine
Part 1 Lid QC
Part 1 Lid Packaging 2,0%
Part 2 Cup IM
Part 2 Cup QC
Part 2 Cup Packaging 2,0%
Part 1 Lid - Rejected 5.0%
Part 2 Cup - Rejected 5.0%
Part 1 Lid- Final Product 13%
Part 2 Cup – Final Product 13%
VI
Table D-3: Production system equipment - classification and allocation results per quantity centre
Qc Equipment Type And Allocation
Raw material area Fork Lift, Electric Stacker,
Manual Stacker (Two) Non-Dedicated – 43%
Hopper Dryer Vacuum Pumps (Two), Hopper
Dryer Dedicated – 100%
Part 1 – Injection
Injection Machines, Moulds
And Accessories (Three)
Chillers
Dedicated – 100%
Non-Dedicated – 50%
Part 2 – Injection
Injection Machines, Moulds
And Accessories (Three)
Chillers
Dedicated – 100%
Non-Dedicated – 50%
Part 1 – Quality Control Easy – Open Machine Dedicated – 100%
Part 2 – Quality Control Poka-Yoke Dedicated – 100%
Part 1 – Packaging Weight Scale
Manual Stacker
Dedicated – 52%
Non-Dedicated – 22%
Part 2 – Packaging Weight Scale
Manual Stacker
Dedicated – 48%
Non-Dedicated – 22%
Part 1– Final Product
Warehouse
Stretch Wrapper, Electric
Stacker, Manual Stacker (Two),
Electric Fork-Lift (Two)
Non-Dedicated – 11%
Part 2 – Final Product
Warehouse
Stretch Wrapper, Electric
Stacker, Manual Stacker (Two),
Electric Fork-Lift (Two)
Non-Dedicated – 43%
Part 1 – Waste Management
(Rejected) Shredding Machine Non-Dedicated – 22%
Part 2 – Waste Management
(Rejected Shredding Machine Non-Dedicated – 22%
VII
Annex E – Analysis to reduce the number of mouldings
rejected after stops
Considering the production conditions:
• machine 27 produces 32 lids each moulding, 40 produces 28 lids each moulding and 28
produces 15 lids each mounding.
• the daily maintenance is performed every 8 hours and the production system works 24h/day
• Is possible to reduce 15 mouldings
Is possible to save 1 231 875 products per year
Easy Open Test - Reference number kgf>5.5 and kgf<11.5
Machine 27 40 28
Moulding 5th 10th 15th 20th 5th 10th 15th 20th 5th 10th 15th 20th
Cavity Kgf
1 9.1 9.1 9.12 9.14 8.94 8.98 8.88 8.81 10.2 10.2 10.1 10.1
2 9.3 9.31 9.3 9.29 9.54 9.94 9.11 9.55 9.35 9.4 9.3 9.25
3 9.4 9.35 9.2 9.16 9.38 9.04 9.15 9.42 8.65 8.54 8.5 8.46
4 9.7 9.6 9.5 9.45 9.69 9.94 9.54 9.64 7.45 7.4 7.48 7.5
5 9.85 9.9 9.8 9.7 9.79 9.76 9.6 9.55 8.23 8.15 8.1 8.96
6 9.12 9.15 9.2 9.16 10.0 10.3 9.62 10.1 9.65 9.7 9.65 9.7
7 9.35 9.34 9.3 9.15 9.72 9.94 9.7 9.25 10.2 10.2 10.2 10.3
8 8.65 8.67 8.7 8.65 9.33 9.96 9.42 9.08 11.2 11.2 11.2 11.1
9 8.36 8.37 8.4 8.3 11.2 11.1 11.4 11.1 10.7 10.8 10.7 10.8
10 9.65 9.5 9.6 9.7 11.3 11.3 11.2 11.2 11. 11.2 11.5 11.1
11 8.45 8.6 8.6 8.7 11.3 11.3 11.4 11.3 11.1 11.1 11.1 11.1
12 7.36 7.4 7.36 7.4
10.2 10.2 10.2 10.2
13 7.41 7.6 7.34 7.15 11.3 11.4 11.3 11.2 10.5 10.7 10.6 10.5
14 7.25 7.8 7.81 7.75
10.9 10.5 10.4 10.4
15 10.6 10.5 10.4 10.3 11.2 11.2 10.7 10.5 8.28 9,00 9.01 9.5
16 10.5 10.9 10.6 10.2
17 11.2 11.1 11.1 11.1 11.3 11.2 11.2 11.2
18 10.6 10.5 10.2 10.2 11.1 11.1 11.3 11.4
19 9.58 9.6 9.4 9.4 11.3 11.3 11.2 11.2
20 11.3 11.4 11.2 11.2 10.9 11.0 10.5 11.0
21 8.45 8.6 8.5 8.5 10.7 10.9 10.1 11.2
22 8.55 8.6 8.4 8.4 11.2 11.2 11.3 11.3
23 9.58 9.6 9.5 9.51 11.2 11.3 10.9 11.0
24 7.56 7.71 7.72 7.7 10.9 11.3 11.0 11.3
25 9.47 9.52 9.6 9.5
26 9.65 9.7 9.5 9.5 9.15 9.94 9.45 9.74
27 8.93 8.94 8.8 8.81 9.93 10.4 9.47 10.0
28 10.6 10.7 10.6 10.7 9.18 9.13 9.23 9.5
VIII
29 10.2 10.3 10.2 10.3 9.5 9.7 10.0 9.98
30 11.2 11.1 11.1 11.1 9.35 9.43 9.28 9.74
31 10.4 10.3 10.4 10.3 9.35 10.6 9.45 10.0
32 11.2 11.3 11.2 11.1 9.57 9.59 9.01 9.99