Effect of Autonomous Maintenance (AM) on Plant Reliability ...

EFFECT OF AUTONOMOUS MAINTENANCE ON PALNT RELIABILITY AND

OVERALL EQUIPMENT EFFICIENCY (A CASE STUDY OF LAFARGE SURMA

CEMENT LIMITED, BANGLADESH)

BY

PROSENJIT DAS

A Thesis work submitted in partial fulfillment of the requirements for the degree of Master of

Advanced Engineering Management

Department of Industrial and Production Engineering

Bangladesh University of Engineering & Technology

APRIL, 2011

ii

CERTIFICATE OF APPROVAL

The thesis work titled " Effect of Autonomous Maintenance on Plant Reliability and Overall

Equipment Efficiency (A case study of Lafarge Surma Cement Ltd., Bangladesh)", submitted

by Prosenjit Das, Roll No.- 100508135, Session- April, 2005 has been accepted as

satisfactory in partial fulfillment of the degree of Master of Advanced Engineering

Management on 16 April, 2011

BOARD OF EXAMINERS

Dr. A. K. M. Masud Professor & Head Department of Industrial and production Engineering BUET, Dhaka-1000

Chairman(Supervisor)

Dr. Abdullahil Azeem Professor Department of Industrial and production Engineering BUET, Dhaka-1000

Member

Dr. Zohrul Kabir Professor Department of MCE, IUT, Gazipur-1704

Member

Department of Industrial and Production Engineering Bangladesh University of Engineering & Technology

Dhaka-1000, Bangladesh.

APRIL, 2011

iii

CANDIDATE’S DECLARATION

It is hereby declared that this thesis or any part of it has not been submitted elsewhere for the

award of any degree or diploma.

Prosenjit Das

iv

ACKNOWLEDGEMENT

It is a great pleasure for me to acknowledge the assistance and contributions of many

individuals in making this dissertation a success.

First and foremost, I would like to thank my supervisor, Dr.A.K.M. Masud, Professor &

Head of IPE, for his assistance, ideas, and feedbacks during the process in doing this

dissertation. Without his guidance and support, this dissertation can not be completed on

time.

Secondly, it is a pleasure to express my thanks to all employees of LSC for their cooperation

and heartiest support to collect all the data. I also like to convey my special thanks to Mr.

Harpal Singh, Sr. Manager- Maintenance and Mr. Ashim K Mondal, Asst. Manager-

Methods, for their constant effort to make me knowledgeable about the incident management

system in LSC. Without their support it was not possible to collect the incident data and

analyze them and understand the total maintenance process that is in practice. I also like to

express my gratitude to Mr. Arun K Saha for his cordial help to access the production budget

which is also considered a confidential document form the company business point of view.

I also like to express my gratitude to Mr. Chang J Song, Plant Manager for his kind approval

to access all the data those are use for internal performance management and allow me to

participates in the reliability committee meetings as well

Lastly, I wish to express my sincere gratitude to my family for their encouragement and

moral support.

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ABSTRACT

This thesis work highlights one of the powerful approaches to improve reliability and

predictability of the plant using Autonomous Maintenance (AM), a pillar of Total Productive

Maintenance (TPM). This explains the underlying concepts, issues, and benefits of AM

implementation through a case study. The company discussed in this study is a Multinational

Company (MNC), manufacturing cement in Bangladesh. Lafarge Surma Cement Limited

(LSCL) has a good organizational structure to support the AM but lack of understanding they

are paying a lot. In this thesis work I collected all the stoppages and segregated them in

different classes. Then all the incidental stoppages were analyzed and identified the stoppages

which could be avoided if the AM was in place. It was also highlighted what is the effect of

those incidental stoppages on Plant Reliability and on Overall Plant Effectiveness. Some

tools were developed to support the LSCL for better management of the stoppages and also

provided some tools to help them implementing the AM. Finally some recommendations

were made based on the findings.

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TABLE OF CONTENTS

CERTIFICATE OF APPROVAL ...................................................................................................................................... II

CANDIDATE‘S DECLARATION ................................................................................................................................... III

ACKNOWLEDGEMENT ............................................................................................................................................... IV

ABSTRACT ..................................................................................................................................................................... V

TABLE OF CONTENTS ................................................................................................................................................ VI

LIST OF TABLES .......................................................................................................................................................... IX

LIST OF FIGURES .......................................................................................................................................................... X

CHAPTER-1: INTRODUCTION .......................................................................................................................................1

INTRODUCTION .............................................................................................................................................................1

1.1 BACKGROUND .................................................................................................................................................1

1.2 PRESENT STATE OF THE PROBLEM ..............................................................................................................1

1.3 IDENTIFICATION AND ASSESSMENT OF OPTION .......................................................................................2

1.4 OBJECTIVE AND SCOPE OF THE STUDY .......................................................................................................4

1.4.1 OBJECTIVE ...................................................................................................................................................4

1.4.2 SCOPE............................................................................................................................................................4

CHAPTER-2: LITERATURE REVIEW .............................................................................................................................6

2.1 OVERVIEW OF TPM IN PROCESS INDUSTRY ...............................................................................................6

2.2 PILLARS OF TPM ..............................................................................................................................................8

2.3 AUTONOMOUS MAINTENANCE ................................................................................................................... 14

2.3.1 EQUIPMENT SELECTION AND TEAM FORMATION .............................................................................. 16

2.3.2 INITIAL CLEANING ................................................................................................................................... 19

2.3.3 ELIMINATE SOURCES OF CONTAMINATION AND INACCESSIBLE AREAS ....................................... 19

2.3.4 ESTABLISH CLEANING AND INSPECTION STANDARDS ...................................................................... 20

2.3.5 ESTABLISHING BASIC EQUIPMENT CONDITIONS ................................................................................ 20

2.3.6 EDUCATION/TRAINING TO OPERATORS AND TECHNICIANS ............................................................ 22

2.4 FEATURES OF PROCESS INDUSTRIES ......................................................................................................... 22

2.5 MAXIMIZING PRODUCTION EFFECTIVENESS IN PROCESS INDUSTRIES .............................................. 25

2.5.1 PRODUCTION EFFECTIVENESS IN PROCESS INDUSTRY ..................................................................... 25

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2.5.2 PROCESSING LOSSES ................................................................................................................................ 25

2.5.3 OVERALL EQUIPMENT EFFECTIVENESS ............................................................................................... 27

2.5.4 MAXIMIZING THE EFFECTIVENESS OF PRODUCTION INPUTS ........................................................... 29

CHAPTER-3: OVERVIEW OF LSCL.............................................................................................................................. 30

3.1 LAFARGE SURMA CEMENT- AT A GLANCE ............................................................................................... 30

3.2 PROCESS DESCRIPTION ................................................................................................................................ 30

3.2.1 CRUSHING SYSTEM .................................................................................................................................. 31

3.2.2 RAW GRINDING SYSTEM ......................................................................................................................... 31

3.2.3 BURNING SYSTEM .................................................................................................................................... 33

3.2.4 FINISH GRINDING SYSTEM ...................................................................................................................... 34

3.2.5 PACKING & DISPATCH ............................................................................................................................. 35

3.3 MAINTENANCE DEPARTMENT-LSC ............................................................................................................ 35

3.4 MAINTENANCE PHILOSOPHY ...................................................................................................................... 39

3.5 DOWNTIME AND KPI IN LSCL ...................................................................................................................... 40

3.5.1 DOWN TIME RECORDING ......................................................................................................................... 40

3.5.2 OPERATING HOURS .................................................................................................................................. 41

3.5.3 HOURS OF STOPPAGE ............................................................................................................................... 41

3.5.4 PERFORMANCE INDICATORS FOR LSC .................................................................................................. 42

3.5.5 CLASSIFICATION OF DOWNTIME ........................................................................................................... 44

CHAPTER-4: DATA COLLECTION AND ANALYSIS .................................................................................................. 48

4.1 DATA COLLECTION ....................................................................................................................................... 48

4.2 STOPPAGES ANALYSIS ................................................................................................................................. 50

4.2.1 STOPPAGES DISTRIBUTION BY DISCIPLINE.......................................................................................... 50

4.2.2 PARETO ANALYSIS ................................................................................................................................... 50

4.2.3 ROOT CAUSE ANALYSIS (RCA) ............................................................................................................... 57

4.3 EFFECT OF AM ON RELIABILITY ................................................................................................................. 59

4.3.1 BURNING SYSTEM .................................................................................................................................... 59


4.3.3 FINISH GRINDING SYSTEM (LINE-1) ....................................................................................................... 60


4.4 EFFECT OF AM ON OEE ................................................................................................................................. 62

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4.4.1 BURNING SYSTEM .................................................................................................................................... 62




CHAPTER-5: RESULTS AND DISCUSSIONULTS AND DISCUSSION ........................................................................ 65

5.1 RESULTS.......................................................................................................................................................... 65

5.2 DISCUSSION .................................................................................................................................................... 66

CHAPTER-6: CONCLUSION AND RECCCOMMENDATION ...................................................................................... 77

6.1 CONCLUSION.................................................................................................................................................. 77

6.2 RECOMMENDATION ...................................................................................................................................... 82

REFERENCES ................................................................................................................................................................ 83

APPENDIX ..................................................................................................................................................................... 85

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LIST OF TABLES

Table No. Title Page

3.1 Example of RF & UF Calculation 44

4.1 Sample data analysis for proper allocation of incidental stoppages 49

4.2 Pareto analysis of stoppages in Burning System 52

4.3 Pareto analysis of stoppages in Raw Grinding System 53

4.4 Pareto analysis of stoppages in Finish Grinding System (Line-1) 54

4.5 Pareto analysis of stoppages in Finish Grinding System (Line-2) 56

5.1 Present status of plant performance and effect of AM 67

6.1 Checkpoints for Nut & Bolts Inspection 74

6.2 Checkpoints for Electrical Equipment Inspection 74

6.3 Checkpoints for Hydraulic Equipment Inspection 76

6.4 Checkpoints for Pneumatic Equipment Inspection 77

6.5 Checkpoints for Transmission Equipments Inspection 78

6.6 Lubrication points inspection checkpoints 78

6.7 Checkpoints for General Purpose Equipment Inspection 79

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LIST OF FIGURES

Figure No. Title Page

2.1 Pillars of TPM 9

2.2 Causes and accelerated deterioration 21

2.3 Production Effectiveness in Process Industries 25

2.4 Eight Major Losses 27

3.1 Raw Material Extraction and Crushing 32

3.2 Vertical Raw Mill 33

3.3 Raw Mill Feed Preparation 33

3.4 Kiln 35

3.5 Coolax Cooler 35

3.6 Finish Grinding Process 36

3.7 Organizational Structure 37

3.8 Maintenance Function 38

3.9 Organization Chart-Maintenance 39

3.10 Organization Chart-Mechanical Maintenance 39

3.11 Organization Chart- Methods 40

3.12 Organization Chart-Instrumentation & Controls and Maintenance 40

3.13 ADAP 42

4.1 Distribution of Stoppages by percentage among different departments 51

4.2 Pareto Analysis for Burning System 52

4.3 Pareto Analysis for Raw Mill Grinding System 54

4.4 Pareto Analysis for Finish Grinding System (Line-1) 55

4.5 Pareto Analysis for Finish Grinding System (Line-2) 57

4.6 RCA Sample 59

5.1 Present status of plant RF and effect of AM 70

5.1 Present status of plant OEE and effect of AM 70

6.1 Distribution of maintenance activities within the discipline 81

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DEFINITIONS AND ABBREVIATIONS

AM Autonomous Maintenance

Apparent Cause The Equipment which causes the stoppages of the

process system CHSIM Cummulitative hours of stoppages due to Mechanical

incidents CHSIE Cummulitative hours of stoppages due to Electrical

incidents CHSIF Cummulitative hours of stoppages due to Production

incidents CHSIO Cummulitative hours of stoppages due to others

incidents Cause Underlying reason that cause the equipment stoppage

CHS Cummulitative hours of Stoppages

CHSI Cummulitative hours of stoppages due to incident

CHSP Cummulitative hours of Planned Stoppages

CHSC Cummulitative hours of stoppages due to Circumstance

WH Working Hours

LSCL Lafarge Surma Cement Limited

MTTR Mean Time To Repair

MTBF Mean Time Between Failure

MMT Million Metric Ton

NS Number of Stoppages

NSFI Number of Stoppages due to Incident

NSFP Number of Scheduled stoppages

NSFC Number of stoppages due to Circumstances

NSFIM Number of stoppages due to Mechanical Incident

NSFIE Number of stoppages due to Electrical Incident

NSFIF Number of stoppages due to Production Incident

NSFIO Number of stoppages due to Other Incident

OEE Overall Equipment Efficiency.

OH Operating Hours

PD Work Generated by Predictive Maintenance)

PG Work Generated by Preventive Maintenance

PF Performance Factor.

PM Preventive Maintenance

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RF Reliability Factor

RCA Root Cause Analysis

TPM Total Productive Maintenance

TQM Total Quality management

SOP Standard Operating Procedure

UF Utilization Factor

316FA01, 416LU01 Primary Air Fan, Lubrication Unit for Cement Mill 1

Drive (Lafarge codification system)

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CHAPTER-1: INTRODUCTION

INTRODUCTION

1.1 Background

Lafarge Surma Cement Ltd. (LSCL) is an integrated cement manufacturing company in

Bangladesh. Lafarge Group of France, one of the world leaders in building materials is the

majority shareholder of LSCL. Although LSCL competes with a large number of cement

manufacturers in the country, it has a few unique advantages. While all other manufacturers

import clinker, only LSCL has the capacity to manufacture clinker in-house using limestone

from a owned quarry. [1]

In terms of cement production, Bangladesh ranks about 40th in the world. Cement

manufacturing is a highly fragmented business in Bangladesh. During the 1990s, many small

cement companies entered the market as soon as the government started encouraging local

production with favorable tariff differential. Currently 123 companies are listed as cement

manufacturers in the country. Of them 63 have actual production capacity while about 30 do

not have any production at all. The current installed capacity is 22.0 MMT. However,

because of supply constraints for power and clinkers, the actual capacity is about 17.0

MMT.[2] Bangladesh is one of the few sizable producers of cement that does not have its

own supply of limestone and cannot produce clinkers domestically. Except for LSCL, all

other cement manufacturers of Bangladesh are in essence grinders of clinkers. There is a

strong tax-support for local cement manufacturers in Bangladesh. They receive a significant

import tax advantage over finished cement (about 15% for raw-materials versus 100% for

finished cement). This tariff differential helps most to operate profitably. A change in the

tariff structure is not anticipated in the near future [2].

1.2 Present state of the problem

The industry realized about 20% sales growth in 2009, mostly because of the latent demand

from last years. On a secular basis, ongoing demand growth is expected to be about 8%, the

outlook for the cement industry seems positive for a number of reasons. First, the government

seems to be on a war footing to increase both the amount and the efficiency of spending in

2

social and physical infrastructure under the Annual Development Programs (ADP). Second,

the private sector is also energized because of certain tax advantages for undeclared funds if

they are invested in real estate. Third, a number of large infrastructure construction projects

(such as the Padma Bridge) are on the horizon. Both the government and the private sector

are soliciting funds for such projects. If implemented, these projects would significantly

improve demand for construction materials.

The largest 10 cement manufacturers hold about 70% of the market share. While Heidelberg,

Holcim and Cemex are the leaders among multinational cement manufacturers; Shah, Akij

and MI are the leading domestic manufacturers. Shah cement is the market leader with close

to 12% of the market share, closely followed by Heidelberg with about 10% of the market

share.[2]

Being the market leader in the building material on the glove LSCL is having only 8% (2008)

market share in the Bangladesh cement market. To cost recovery they need more revenue

which can be achieved by lowering the production cost or/and increasing the sales i.e.

capturing more market share. Lafarge is enjoying a superior supply change system specially

in the distribution system as the plant is located on the bank of Surma river with a

experienced and well structured marketing team which can ensure the creating demand for

their product ―SuperCreate‖ in near future. So now the challenge is to increase the

production to meet the increasing market demand as well as lowering the manufacturing cost

[1].

1.3 Identification and assessment of option

Although LSCL competes with a large number of cement manufacturers in the country, it has

a few unique advantages. While all other manufacturers import clinker, only LSCL has the

capacity to manufacture clinker in-house using limestone from a owned quarry. This provides

the company the benefit of significantly higher gross margins. Because of its affiliation with

Lafarge worldwide, LSCL is considered a leading brand in a competitive market, and it

enjoys price premium because of a perceived quality leadership. Lastly, Lafarge has one of

the largest production plant in the industry (1.2MT, expandable to 1.5MT) [1]. In a

fragmented industry where smaller producers are being gradually squeezed out of the market,

LSCL has the advantage of scale. As and when consolidation starts in the market, LSCL

stands prepared to benefit because of its staying power [2].

3

Demand for cement was particularly weak in 2007-08 for several reasons. First, the anti-

corruption drive of the military-backed caretaker government subdued expenditure of

undeclared funds. Most of these funds usually go to the construction sector. Second, a rapid

climb of raw materials and shipping costs in the global market escalated the price in the local

market for cement and other construction materials, further squeezing consumers out of the

market. Third, government spending in construction under the annual development programs

(ADP), which constitutes a large part of the cement market, was particularly slow in these

years. Consequently, many of the smaller and some major cement manufacturers operated at

less than 50% capacity and incurred large losses during these years [2].

The industry realized about 20% sales growth in 2009, mostly because of the latent demand

from last years. On a secular basis, ongoing demand growth is expected to be about 8%. The

outlook for the cement industry seems positive for a number of reasons. First, the government

seems to be on a war footing to increase both the amount and the efficiency of spending in

social and physical infrastructure under the Annual Development Programs (ADP). Second,

the private sector is also energized because of certain tax advantages for undeclared funds if

they are invested in real estate. Third, a number of large infrastructure construction projects

(such as the Padma Bridge) are on the horizon. Both the government and the private sector

are soliciting funds for such both the government and the private sector are soliciting funds

for such projects. If implemented, these projects would significantly improve demand for

construction materials [1, 2].

So to meet the increased the demand it is essential to increase the productivity. The

approaches that are applicable at the shop-floor level are the ones that have direct impact on

the productivity. The second industrial revolution that was triggered in 1970s saw the advent

of automation in the shop floor. Automation became popular among Japanese manufacturers.

Automation eliminates the drudgery of manual labor, improves the quality, and reduces costs.

However, automation fails if the equipments are not maintained properly. Japanese

manufacturers started to move towards an approach that would guarantee Zero Accidents,

Zero Defects, and Zero Breakdowns [3, 4].

Thus, TPM (Total Productive Maintenance) came into existence. One of the main pillars of

TPM is Autonomous Maintenance (Tajiri and Gotoh, 1992). The uniqueness of Autonomous

Maintenance is that the maintenance is carried by the Production Department (shop-floor

4

personnel) [4] and not by the conventional Maintenance Department. The success of TPM

depends upon the success of the Autonomous Maintenance program.

1.4 Objective and Scope of the study

1.4.1 Objective The main objective of this study is to evaluate the effect of AM on the plant

reliability, utilization factor as well as on overall plant effectiveness which will also

includes-

Management of the stoppages (unwanted plant shutdown)

Study and identification of the incidental stoppages which are manageable by

implementing AM

1.4.2 Scope The scope of the study includes

(i) The cement manufacturing process

(ii) Maintenance Management System of LSCL

(iii) Performance Criteria of LSCL

(iv) Collection of the data for all the stoppages

(v) Analyzing the data

(vi) Calculation of reliability factor

(vii) Calculation of utilization factor

(viii) Calculation of performance factor

(ix) Calculation of overall equipment efficiency

The following steps were carried out to complete the project was sequentially:

(a) Data Collection

In LSCL the stoppages are automatically log in into a software named ADAP (Advance

Downtime Analysis program), and then manually segregated the stoppages in their

different types. I collected all the data and segregate the incidental stoppages.

(b) Data Analysis /RCA

Data Analysis phase includes to identify the stoppages in different categories and to select

the stoppages which are due to lack of autonomous maintenance i.e. which can be

5

avoided by implementing the Autonomous Maintenance by the means of RCA. I also find

the duration of the stoppages and justify how those stoppages can be avoided by

implementing AM.

(c) Pareto Analysis

After that I carried out the Pareto analysis to find the main contributor in the loss of

reliability. Only the major incidents those who are contributor in the 80% of total loss in

reliability will be addressed.

(c) Calculating Effect on Reliability

Then I calculated the effect of individual stoppage on the Reliability of the particular shop

and as well as the plant reliability. In LSC the shops are VRM (Vertical Raw Mill),

KILN, CM1 (Cement Mill-1), CM2 (Cement Mill-2).

(d) Calculating Effect on OEE

I also calculated the OEE relating with RF, PF and UF. So an increase in RF will

definitely affect the OEE of a plant. Here I calculated the increased OEE resulting from

the increase in RF.

6

CHAPTER-2: LITERATURE REVIEW

LITERATURE REVIEW

2.1 Overview of TPM in Process Industry

Japan‘s process industries introduced preventive maintenance (PM) relatively early because

production output and rate, quality, safety, and the environment depend almost entirely on the

state of plant and equipment. The preventive and productive maintenance systems introduced

by Japanese process industries played a major role in improving product quality and

productivity [4].

They contributed significantly to overall process in maintenance management and expertise

in such areas as setting up specialized maintenance organizations, creating equipment

management systems, improving equipment technology, and raising maintenance

productivity.

While the process industries focused on preventive and productive maintenance, the

fabrication and assembly industries invested heavily in new equipment in an effort to become

less labor intensive. The equipment used by these industries has become increasingly

automated and sophisticated, and Japan is now the world leader in the use of industrial

robots. This trend toward automation, combined with the trend toward just-in-time

production, stimulated interest in improving maintenance management in the fabrication and

assembly industries [3].

This gave birth to a uniquely Japanese approach called total productive maintenance (TPM),

a form of productive maintenance involving all employees.

TPM first took root in the automobile industry and rapidly became part of the corporate

culture in companies such as Toyota, Nissan, and Mazda, and their suppliers and affiliates. It

has also been introduced by other industries, such as consumer appliances, microelectronics,

machine tools, plastics, film, and many others [5].

Having introduced preventive maintenance, the process industries then began to implement

TPM. An increasing number of process plants have introduced TPM over the past few years

in industries such as food, rubber, oil refining, chemicals, pharmaceuticals, gas, and cement,

papermaking, iron and steel, and printing [3].

7

Initially, corporate TPM activities were limited to departments directly involved with

equipment, such as production, however, administrative and support departments, while

actively supporting TPM in production, are now applying TPM to enhance the effectiveness

of their own activities, TPM improvement methods and activities are also being adopted in

production development and sales departments.

This last trend underlines the increasing tendency to consider production process as

equipment at the product development stage in an effort to simplify production, improve

quality assurance, and enhance and reduce the startup period for new production. These

issues are of particular concern in process industries today as product diversification

continues and product life cycles shorten. Interest in TPM outside Japan has also expanded in

recent years. Many companies in the United States, Europe, Asia, and South America are

Planning to or are actively pursuing TPM.

There are three main reasons why TPM has spread so rapidly throughout Japanese industry

and why companies outside Japan are becoming interested: It guarantees dramatic results,

visibly transforms the workplace, and raises the level of knowledge and skill in production

and maintenance workers.

Companies practicing TPM invariably achieve starting results, particularly in reducing

equipment break-downs, minimizing idling and minor stops (indispensable in unmanned

plants), lessening quality defects and claims, boosting productivity, trimming labor and costs,

shrinking inventory, cutting accidents, and promoting employee involvement.

Through TPM, a filthy, rusty plant covered in oil and grease, leaking fluids, and spilt

powders can be reborn as a pleasant, safe working environment. Customers and other visitors

are impressed by these changes, and their confidence in the plant‘s products increases.

As TPM activities begin to yield concrete results (improving the working environment,

minimizing breakdowns, improving quality, reducing changeover times, and so on), workers

become motivated, involvement increase, and improvement suggestions proliferate. People

begin to think of TPM as part of their Job.TPM helps operators understand their equipment

and widen the range of maintenance and other tasks they can handle. It enables them to make

new discoveries, acquire fresh knowledge, and enjoy new experiences. It strengthens

motivation, engenders interest in and concern for equipment, and fosters the desire to

maintain equipment in peak condition [6~10].

8

2.2 Pillars of TPM

There are three mainly eight pillars in the TPM. Which are-

1. Pillar-1: Focused Improvement

2. Pillar-2: Autonomous Maintenance

3. Pillar-3: Planned Maintenance

4. Pillar-4: Training

5. Pillar-5: Early Management

6. Pillar-6: Quality Maintenance

7. Pillar-7: Office TPM

8. Pillar- 8: Safety and Environmental Management

Pillar-1: Focused Improvement

Focused improvement is an improvement activity performed by cross-functional project

teams composed of people such as production engineers, maintenance personnel, and

operators, these activities are designed to minimize targeted losses that have been carefully

measured and evaluated.

In addition to the seven major losses experienced in fabrication and assembly industries,

process industries sustain three additional types of loss: people related losses such as work

and mis-operation losses; raw-materials losses such as yield, unit-consumption, and recycling

losses; and management losses such as shutdown maintenance and energy losses.

In process industries, focused improvement activity is directed at a specific object such as a

process, a flow system an item of equipment, or an operating procedure. For example,

process design must be an integral part of product development and improvement. A focused

improvement project can address vital, related issues such as establishing criteria for

selecting processes and their conditions, discovering deficiencies in process conditions, and

finding and closing gaps between actual and ideal process conditions.

The trend toward unattended operation is well advanced in process industries and will

probably be taken even further in the future. For this reason, ideas for stabilizing processes

and eliminating equipment breakdowns, idling, and minor stops are also important topics for

focused improvement.

When the focus is strictly on equipment, project teams follow a similar approach to that

developed in fabrication and assembly industries. They document and analyze the major

9

equipment-related losses, then study the equipment carefully to identify the process

conditions it is required to provide and to ensure that it can fulfill them.

Whether the focus is on the process, work flow, equipment, or operation procedures,

however, focused improvement activity is founded on effective use of cause analysis

methods, such as why-why analysis and P-M analysis [11]

Fig 2.1: Pillars of TPM

Pillar-2: Autonomous Maintenance

Autonomous maintenance is one of the most distinctive activities in TPM. After preventive

maintenance was introduced into Japan, Operation and maintenance were formally separated,

as operators lost ownership of their equipment; they gradually lost their sense of

responsibility for maintaining it.

10

The autonomous maintenance practiced in TPM reverses this tendency. Operators become

involved in routine maintenance and improvement activities that declined the deterioration

rate by halves, control contamination, and help prevent equipment problems.

Because process plants employ a small number of operators in relation to the number and size

of equipment units, strategies for achieving autonomous maintenance goals must be adapted

somewhat from the traditional approach followed in fabrication and assembly industries.

When tailoring autonomous maintenance to individual process environments, planning teams

must consider

how autonomous maintenance steps can be conducted most effectively on different

types of equipment

Investigate the relative importance of different equipment items and determine

appropriate maintenance approaches.

Prioritize maintenance tasks

Allocate responsibilities appropriately between production and specialized

maintenance personnel

Autonomous maintenance activities are typically implemented in steps and are only effective

if the progression form one step to the next is strictly controlled. To manage this, appoint

official auditing groups and lay down pass/fail standards. A plant‘s top management should

give final approval for groups to graduate from one step and move on to the next.

Why is close control so important? Initial cleaning (pillar-1), for example, involves much

more than merely cleaning and tidying the equipment and adjacent areas. If team efforts are

not focused on identifying and treating problems found in the course of thorough cleaning,

the goals of eliminating and controlling deterioration cannot be achieved.

Similarly, depending on the plant‘s location, salt spray, rain, snow, and so on, liquids, solids,

gases, etc can also accelerated deterioration of equipment, through scattering, leaking, blocks

and so forth. How such deterioration is treated will depend in part on the environment, the

equipment, or form of the product. However, if Step 2 of an autonomous maintenance

program (action against contamination sources and inaccessible places) is not properly

implemented, the program will slip right back to step 1 or step 1 or even further. Step-by-

step auditing of team activities to keep them properly focused is essential for successful

implementation of autonomous maintenance [1, 2, 11]

11

Pillar-3: Planned Maintenance

Planned or scheduled maintenance, embraces three forms of maintenance: breakdown,

preventive, and predictive. Like other TPM activities, building a planned-maintenance system

can be done systematically, one step at a time.

The purpose of performing predictive and preventive maintenance is to eliminate

breakdowns, but even when systematic maintenance practices are carried out, unexpected

failures still occur, of maintenance plans and highlight ineffective recurrence-prevention

measures. In TPM, Planned maintenance a activities emphasize monitoring mean times

between failures (MTBF) and using that analysis to specify the intervals for tasks in annual,

monthly, and weekly maintenance calendars [9~12]

A classic example of planned maintenance activity is shutdown maintenance. To make

them more effective, companies are preparing for shutdown earlier and earlier. Their goal is

to lay out reliable plans before the job begins. Because the tasks performed during shutdown

maintenance follow a set pattern, it is helpful to base the work plan on a work breakdown

structure (WBS) diagram. This diagram facilitates accurate estimation of the tasks to be

performed during shutdown maintenance, along with their sizes. It can be used to gauge the

staff and materials needed for the job and to monitor the budget and the achievement of the

objectives [5, 9, 10 ].

Pillar-4: Training

A company‘s workforce is a priceless asset, and all companies must train their employees

systematically. Process-industry Workers are becoming increasingly elite, and more multi

skilled. So training must be an integral part of a career development system.

Visualize the type of people you want your training programs to produce. In other words,

identify the specific knowledge, skills, and management abilities you want them to have and

then design training that will achieve your vision.

Training must also be tailored to serve the individual‘s needs. Assess each person to measure

his or her grasp of the required knowledge and skills and pinpoint weaknesses, the use the

results to make the general training more effective. Workers and their supervisors should

discuss the results of this assessment annually and use them to set the next year‘s targets and

plan the next phase.

Also set firm schedules for achieving program targets. Decide the king of people you want to

have in how many year‘s time, the draw up comprehensive plans for on-the-job and off-the-

job training (including seminars and courses) designed to achieve this [5, 11]

12

Pillar-5: Early Management

Early management includes both early product management and early equipment

management. The purpose of these activities is to achieve - quickly and economically -

products that are easy to make and equipment that is easy to use. This section highlights early

equipment management.

Early equipment management concerns equipment users, engineering companies, and

equipment manufactures, and addresses the following areas-

Equipment investment planning

Process design

Equipment design, fabrication, and construction

Test operation

Startup management.

All activities from the initial design of a piece of equipment to its installation and test

operation can view as a single, giant project. The project starts with process design, basic

plant design, and detailed design and unfolds to include procurement, fabrication,

construction, and test operation. In planning such a project, the project team determines the

plant and equipment‘s required technical levels (functions and performance) together with its

availability levels (reliability, maintainability, etc.) and then establishes budgets and

schedules to achieve them.

In designing a plant, various designs are performed: functional design, reliability and

maintainability design, safety design, and economy design. Establishing maintenance

prevention (MP) specifications and performing MP design, in particular, help ensure that the

plant and equipment are reliable and easily maintained. Several design reviews should be

performed in the course of designing, fabricating, and constructing a plant.

After completing these activities, teams install the equipment, perform test operation, and

initiate the startup management phase. Startup management is an activity designed to achieve

as quickly as possible the conditions for its own termination, that is, conditions that enable

the plant to start producing stable quality product with zero failures. In TPM this efficient

approach to stable, full scale production is known as ―vertical startup‖ [3, 9,11]

13

Pillar-6: Quality Maintenance

Quality maintenance (QM) is a method for building in quality and preventing quality defects

through the process and through the equipment, in quality maintenance, variability in a

product quality characteristic is controlled by controlling the condition of equipment

components that affect it.

Quality characteristics are mainly influenced by the four production inputs: equipment,

materials, people‘s actions (skills), and methods used. The first step in quality maintenance is

to clarify the relationships between these factors and a product‘s quality characteristics by

analyzing quality defects. In process industries, the effect of equipment on quality

characteristics is particularly important.

In process industries, the process determines the type of equipment needed. Therefore, teams

should focus first on the process, then on the equipment. In other words, first clarify the

relationships between product quality and process conditions and ascertains the precise

process conditions required for producing perfect product.

Equipment is a means of implementing a process. Therefore, applying a QM approach in

equipment design, teams begin by identifying the components that will affect the product‘s

quality characteristics. These are called ―quality components.‖

Next, they pinpoint the quality component conditions required to maintain the quality

characteristics. Quality maintenance used in this way assures quality at the very beginning of

the production process [5, 7, 11].

Pillar-7: Office TPM

Administrative and support departments play an important role in backing up production

activities. The quality and timeliness of the information supplied by administrative and

support has a major impact on these activities.

TPM activities performed by administrative and support departments must not only support

TPM in the workplace; they should also strengthen the functions of the departments

themselves by improving their own organization and culture. Compared with production,

however, it is not as easy for administrative and support departments to measure the effects of

their activities. [4, 8 , 10].

A TPM program in such a department must aim to create an ―information factory‖ and apply

process analysis to streamline the information flow. Think of administrative and support

departments as process plants whose principal tasks are to collect, process, and distribute

14

information. This understanding makes it easier to promote and measure maintenance,

focused improvement, and other TPM activities in an office environment.

Autonomous maintenance in administrative departments aims for efficient, trouble-free work

execution from two angles: administrative function and administrative environment.

Implemented step by step, the first set of activities reduces costs and boost efficiency by

improving administrative processes.

The second set of activities removes obstacles to effective work hidden in the physical and

psychological environment. Focused improvement of administrative tasks aims to improve

their efficiency and speed and reduce the number of staff required. To achieve this, automate

office tasks and install electronic data-processing system. At the same time, increase

administrative efficiency to support the planning and decision-making of executives and

managers.

Pillar- 8: Safety and Environmental Management

Assuring safety and preventing adverse environmental impacts are important issues in

process industries.

Operability studies combined with accident prevention training and near-miss analysis are

effective way of addressing these concerns. Safety is promoted systematically as part of TPM

activities. As with all TPM activities, safety activities are implemented step by step. Certain

issues are of particular importance in the process environment. For example, it is particularly

important to incorporate fail-safe mechanisms - that is, to design equipment that will remain

safe even when people do not take the proper precautions. Assuring safety during shutdown

maintenance is also important. In process industries, shutdown maintenance requires

considerable assistance from outside subcontractors, as do operation such as cleaning. This

makes it doubly important to ensure safety during such operations. Check the skills and

qualifications of subcontract workers well in advance whenever possible. Take every

practicable step to assure safety, including giving rigorous safety training and carefully

supervising the work itself [11].

2.3 Autonomous Maintenance

TPM refers to small group activities calling for total employee involvement and implemented

primarily by the production, maintenance, and plant engineering departments to maximize

15

productivity. In short, it is a strategy to realize Zero Accidents, Zero Defects, and Zero

Breakdowns (Gotoh, 1991; Tajiri and Gotoh, 1992).

TPM implementation must take into account the conditions that exist in each company or

factory, such as plant configuration, organization, local history, and culture at the plant site.

In today‘s industrial scenario huge losses/wastage occur in the manufacturing shop floor.

This waste is due to operators, maintenance personal, process, tooling problems and non-

availability of equipment in time etc. Other forms of waste includes idle machines, idle

manpower, break down machine, rejected parts etc are all examples of waste. The quality

related waste are of significant importance as they matter the company in terms of time,

material and the hard earned reputation of the company. There are also other invisible wastes

like operating the machines below the rated speed, start up loss [4], break down of the

machines and bottle necks in process. Zero oriented concepts such as zero tolerance for

waste, defects, break down [7] and zero accidents are becoming a pre-requisite in the

manufacturing and assembly industry. TPM is the revolutionary concept in this aspect. One

of the important pillars of the TPM is Autonomous maintenance [3], by which the machine

downtime and unavailability related loss can be eliminated.

In another version, autonomous maintenance is called self maintenance. Self maintenance

which geared towards developing production operators to be able to take a care of small

maintenance task, thus freeing up the skilled maintenance people to spend time on more

value added activity and technical repairs. The operators are responsible for upkeep of their

equipment to prevent it from deteriorating. This feeling can appear with joining all level

management starting from top management to bottom management. They work together to

solve machine problem, then give a thrust to operator to maintain by himself after they pass a

kind of machine operation setting skill test. On its development, many tools and methods are

used to speed up the skill level of operator to take a good care for machine. In the next step of

self maintenance, FMEA (Failure Mode Effect Analysis) [6,7,12] method has been started to

analyze the problem. It is held by maintenance together with production and engineering, and

its impact really felt to reduce machine problem moreover reach no breakdown machine on

production time. Moreover, another method to level up production side to do well self

maintenance is using Production-Maintenance mechanism. This motto does not only raise up

the spirit of production to do maintain their machine hardly but also on maintenance side

which feel that they have to study more and more to level up their skill because the next

demand will be different whereas maintenance not just stand to fixed up a simple problem but

drive to be a specialist one [9].

16

AM implementation process may be interpreted as a process of organizational change (Fruin,

1997). One model of organizational change is based on cycles of compliance which refers to

the conforming or nonconforming behavior of those who are in the midst of organizational

change, measured against the expectations and performance goals of those in charge of

planning and managing change. The model predicts that large-scale change activities move

through a predictable sequence of four phases: education and promotion; commitment;

performance; decline and withdrawal.

The main goal of Autonomous Maintenance is as follows.

Prevent equipment deterioration through correct operation and daily checks

Bring equipment to its ideal state through restoration and proper management

Establish the basic conditions needed to keep equipment well-maintained

The steps to be followed in the AM program are (Motorola Internal Document, 1999):

2.3.1 Equipment selection and team formation

Selection of the right equipment during the initial stages of implementation of AM is very

important. A quick success in the initial stages will always provide sufficient momentum

to the whole TPM program. TPM emphasizes on cross-functional teams. The team members

must be from departments like Engineering, Equipment, and Manufacturing. By having a

cross-functional team all aspects can be looked into and each team member is given a specific

task to accomplish.

Today, the relationship between production and maintenance departments is often

adversarial. When production stops due to equipment failure, production departments

complain bitterly:‖Maintenance doesn‘t know its job‖; ―It takes too long to fix the

equipment‖; or, ―this equipment is so antiquated, no wonder it breaks down.‖ Then they say

they are too busy to do vital daily checks. [11]

17

Maintenance Techniques and Activities

The maintenance activities can be classified in different ways but the most effective away is

as mentioned below.

Normal Operation Correct operation, correct adjustment, correct setting

(prevention of human errors)

Preventive Maintenance Daily maintenance (basic equipment conditions, checking,

minor servicing)

Periodic maintenance (periodic checking, periodic overhaul

inspection, periodic servicing)

Predictive Maintenance Condition monitoring, medium-interval and long-interval

servicing

Breakdown Maintenance Prompt abnormality detection, emergency repairs,

recurrence prevention (troubleshooting)

Improvement Activities:

Extend Equipment life

Shorten the time require to perform maintenance

Make maintenance unnecessary

All the maintenance activities are the responsibility of all the personnel in the organization

and they are can be listed as below…

Activities of the Production Department

1. Preventing deterioration:

Correct operation — preventing human errors

Correct adjustment — preventing process defects (quality defects)

Basic housekeeping (establishing basic equipment conditions) — cleaning,

lubricating, and tightening

Early prediction and prompt detection of abnormalities — forestalling failures and

accidents

Keeping maintenance records — feeding back information for recurrence prevention

and maintenance-prevention design

18

2. Measuring deterioration:

Daily inspection — patrol checks and five-senses checks during operation

Periodic inspection — part of overhaul inspection during plant shutdown or

shutdown maintenance

3. Predicting deterioration:

Minor servicing — emergency measures when abnormal conditions arise and simple

parts replacement

Prompt, accurate reporting of failures and problems

Assistance with repairing unexpected failures

Maintenance Department Activities

Provide instruction in inspection skills and help operators prepare inspection

standards (checkpoints, checking intervals, and so on

Provide training in lubrication techniques, standardize lubricant types, and help

operators to formulate lubrication standards (lubrication points, lubricant types,

intervals, and so on)

Deal quickly with deterioration, minor flaws in equipment conditions, and

deficiencies in basic equipment conditions (I.e., carry out maintenance work

identified by operators promptly)

Contribute technical assistance in improvement activities such as eliminating

contamination sources, making areas more accessible for cleaning, lubrication, and

inspection and boosting equipment effectiveness.

Organize routine activities (morning meetings, rounds to take orders for maintenance

tasks, and so on).

Research and develop new maintenance technologies

Prepare maintenance standards manuals

Build systems for keeping maintenance records, handling maintenance data, and

measuring results

19

Develop and use failure-analysis techniques and implement measures to prevent the

recurrence of serious failures Assist equipment design and development departments

(participate in MP design and early equipment management activities)

Control spares, jigs, tools, and technical data

2.3.2 Initial cleaning

This step emphasizes on hands-on activity. First, the surrounding area is cleaned and all

unnecessary items around the equipment are removed. Once the surrounding area is clean, the

team can start focusing on the equipment itself. Initial cleaning of the machine consists of

cleaning of dust, dirt, grime, oil, grease, and other contaminants in order to expose the hidden

defects inside the equipment. All covers, guards, and compartments should be opened up to

expose the actual condition of the machine. Based on the TPM philosophy ―cleaning is

inspection‖, inspection is a step to detect any abnormalities or ―Fuguai‖. The process of

combing through the machine and identifying all the abnormalities is called ―Fuguai

mapping‖. Figure 1 shows an example of Fuguai mapping. A sketch of the machine is drawn

by hand and fuguais are tagged and classified as long and short-term fuguais. The fuguais are

removed and the progress is monitored closely. The mapping and the removal processes

enable the team to identify the critical cleaning points. Then proper cleaning procedures and

the time taken for cleaning can be established and monitored. The task is explained with a

diagram to facilitate easy understanding to the operator. The ―Cleaning check sheets‖ lists all

the tasks that need to be carried out by the technicians and operators in a very systematic

way. The operators and technicians must be trained and educated on the significance of

cleaning and its impact on the safety. At this stage of AM minor flaws like excessive play,

deformation and wear can be detected and corrected.

2.3.3 Eliminate sources of contamination and inaccessible areas

The basic objective of this step is to identify the sources of contamination and to provide

solutions to permanently correct these sources. This could be done by either eliminating the

source or by containing the contamination in such a way that it does result in losses. This is

done by ―Why Why‖ analysis method. This type of analysis starts with a current problem

being faced and goes through each level of analysis with a ―Why?‖ question. Subsequently

all answers are treated with ―Why?‖ question again. The series of ―Why?‖ helps in

20

identifying the root cause of the problem. The other objective of this step is to identify the

hard-to-access areas for the operator to do the cleaning. The solutions are worked out to make

these areas accessible for cleaning [8].

2.3.4 Establish Cleaning and Inspection Standards

In this step, the focus is on the mechanics of equipment. This step emphasizes on prevention

of any malfunction by studying the lubrication system of the equipment and the equipment as

a whole. Proper lubrication guarantees smooth running of the equipment and reduces the

wear and tear on the equipment. The AM standards are set describing the tasks to be

performed, the tools to be used in performing the task, standard time to be taken to perform

the task, and the frequency of performing the task (daily, weekly etc.). The critical inspection

points on the equipment like gauges, levels are identified and these critical points are added

to the AM standards on cleaning and inspection. However, please note that these standards

are developed after working on preventive solutions to minimize/eliminates cleaning and

inspection time by preventing abnormalities. AM standards are institutionalized and

displayed on the equipment. The technicians and operators can follow this checklist in

maintaining the equipment. It is also important to record the observations made during

cleaning and inspection. The operators must be trained in recording the observations. This

data can be further analyzed to predict any impending problem [11,13]

2.3.5 Establishing Basic Equipment Conditions

Establishing Basic Equipment Conditions Eliminates Causes of Accelerated Deterioration. To

establish the basic condition we need to be familiarized with the different types of failures.

Failures are the consequent of deterioration. This deterioration is normally prevented by the

means of corrective maintenance or by establishment of equipment basic condition. The total

sequence is shown in the figure below.

21

Fig 2.2: Causes of Accelerated Deterioration

For establishment of the Equipment basic condition we need to understand the failure,

defects, deterioration, loss and importance of cleaning and inspection.

Failure

Dirt and foreign matter penetrates rotating parts, sliding parts, pneumatic and hydraulic

systems, electrical control systems, and sensors, etc., causing loss of precision, malfunction,

and failure as a result of wear, blockage, frictional resistance, electrical faults, etc.

Quality Defects

Quality defects are caused either directly by contamination of the product with foreign matter

or indirectly as a result of equipment malfunction.

Accelerated Deterioration

Accumulated dust and grime make it difficult to find and rectify cracks, excessive play,

insufficient lubrication, and other disorders, resulting in accelerated deterioration.

Speed Losses

Dust and dirt increase wear and frictional resistance, causing speed losses such as idling and

under performance.

Key points of Cleaning

1. Clean equipment regularly as part of daily work.

2. Clean deeply - remove all the layers of grime and scale built up over many years.

22

3. Open previously ignored covers, guards, and so on, to expose and remove every speck of

dirt from every corner and crevice.

4. Clean attachments and accessories as well as main units, e.g. conveying equipment, control

boxes, and lubricant tanks (both inside and out).

5. Do not give up when a part gets dirty again soon after cleaning. Instead, carefully note how

long it takes the part to become contaminated again, where the contamination is coming from,

and how severe it is?

Key Points for Inspection

1. Search for invisible as well as visible defects, such as looseness, subtle vibrations, and

slight overheating that only touch can detect.

2. Search carefully for worn pulleys and belts, dirty drive chains, blocked suction filters, and

other problems likely to lead to malfunctions.

3. Note whether equipment is easy to clean, lubricates, inspect, operate and adjust. Identify

hindrances such as large, obstructive covers, ill-positioned lubricators, and so on

4. Ensure that all meters operate correctly and are clearly marked with the specified values.

5. Investigate any leak of product, steam, water, oil, compressed air, and so on.

6. Also hunt for hidden problems such as corrosion inside insulating materials on pipes,

columns, and tanks, and blockages inside chutes and dusts

2.3.6 Education/Training to Operators and Technicians

Unless the operators are trained and educated about the impact the autonomous maintenance

on the quality of the product, scrap rate, and ultimately the cost of production, they will never

be able to appreciate its importance. This step helps in developing ―knowledgeable‖ operators

who can solve/avoid most of the equipment and quality related problems on the shop floor.

AM attempts to achieve Zero Breakdowns, Zero Accidents, and Zero Defects situation on the

shop floor. If AM is implemented in a systematic and phased manner in the shop floor, it can

bring in substantial benefits [7,9,11]

2.4 Features of Process Industries Certain unique features and concerns distinguish process industries from the fabrication and

assembly industries where TPM was born.

23

Diverse production systems

The term ―process industry‖ covers a wide variety of industries including oil refining, patriot-

chemicals, general chemicals, iron and steel, power generation, gas, papermaking, cement,

food, pharmaceuticals, and textiles. Process Plants in these industries employ a mixture of

different production regimes, ranging from completely continuous integrated production to

pure batch production. Also, the trend toward increased product diversification and high-

variety, small-lot production has led in many cases to both process and fabrication/assembly

production in the same plant.

Diverse equipment

In process industries, production processes consist of a combination of unit operations such

as pulverization, dissolution, reaction, filtration, adsorption, concentration, crystallization,

separation, molding, drying, cooling, and screening, together with the handling and

transportation of various substances. Equipment includes static units such as pumps,

compressors, motors, and turbines, and the piping, electrical, and instrumentation systems

that connect them.

Use of static equipment

Static equipment is a particularly noteworthy feature of process industries. The special nature

of such equipment requires TPM quality and includes techniques for diagnosing corrosion,

cracking, burning, blocks, leaks, and so on.

Centralized control and few operators

Unlike in fabrication and assembly industries, control in process industries is centralized.

Many process industries employ continuous, integrated production with centralized control of

large equipment complexes. A wide range of equipment is often controlled by a handful of

operators [13]

Diverse equipment-related problems

In addition to blocks, leaks, and other process problems, process industry equipment is often

plagued by faults such as cracking, rupture, corrosion, seizure, fatigue, slack, parts falling off,

wear, distortion, burning, short-circuiting, faulty insulation, wire breaks,misoperation, current

24

leaks, and overheating. The most common problems, however, are corrosion, leaks, and

blocks.

High energy consumption

Many processes in process industries, such as dissolution, reaction, crystallization, baking,

and drying, are energy intensive and consume large amounts of electrical power, fuel, water,

and so on.

Standby units and bypasses commonly used

To alleviate the effects of breakdowns, it is standard practice to install standby equipment,

bypasses, and so on.

High accident and pollution risk

Some processes handle hazardous or poisonous substances and are operated at high

temperatures and pressures, risking explosion and pollution of the plant and its surroundings.

This makes strict plant management essential, as well as careful adherence to various

statutory regulations

Poor working environment

Intermediate and final products handled in process industries usually consist of bulk powders,

or solids. While it is considered inevitable that the working environment will become dirty as

a result of these being scattered, overflowing, leaking, and so on, such conditions frequently

cause equipment problems.

Shutdown maintenance

Shutdown maintenance is a major feature of process industries. Carefully planned,

systematically implemented shutdown maintenance is considered the most effective way of

preventing breakdowns. However, since shutdown maintenance is time-consuming and labor-

intensive, it is also expensive. Finding the most effective way of performing shutdown

maintenance in view of its cost and the losses it incurs is therefore a perennial concern in

process industries [7].

25

2.5 Maximizing Production Effectiveness in Process Industries 2.5.1 Production Effectiveness in process industry

Production effectiveness in the process industry depends on different input variables. The different input variables and their outputs are shown in the figure 2.3.

Fig 2.3: Production Effectiveness in Process Industry

2.5.2 Processing Losses

The major losses in the process industry are the processing loss. During the processing phase

different types of losses occurs in different stages which are mainly categories into eight

classes. The different process losses are explained below with the help of examples.

The 8 Major Plant Losses

1. Shutdown Loss 2. Production Adjustment Loss 3. Equipment Failure Loss - Function: Failure Loss - Function: Reduction Loss 4. Process Failure Losses 5. Normal Production Losses 6. Abnormal Production Losses 7. Quality Defect Losses 8. Reprocessing

Failure zero Defect zero Problem zero Trouble zero

26

Loss Definition Units Example

1 Shutdown

Loss

Time loss when production

stops for planned annual

shutdown maintenance or

periodic servicing

Days Shutdown work, periodic

servicing, statutory

inspections, autonomous

inspections, general repair

works, etc.

2 Production

Adjustment

Loss

Time lost when changes in

supply and demand require

adjustment to production plans

Days Production adjustment,

shutdown inventory-

reduction, etc

3 Equipment

failure Loss

Time lost when equipment

suddenly losses

Hours Failed pumps, burned

motor, damaged bearings,

broken shafts, etc.

4 Process

failure Loss

Time lost in shutdown due to

external factors such as changes

in chemical or physical

properties of materials being

processed, operating errors,

defective raw material, etc.

Hours Leaks, spills, blocks,

corrosion, erosion, mis-

operation, etc.

5 Normal

Production

Loss

Rate and time losses at plant

startup, shutdown or

changeover

Rate

decreas

e hours

Loss during plat start up,

cool down, shutdown

process

6 Abnormal

Production

Loss

Rate loss due to

underperformance caused by

malfunctions and abnormalities

Rate

decreas

es

Low load operation,

operation at lower than

rated capacity

7 Quality

defect loss

Losses due to producing reject

product, physical losses due to

product downgrading

Hrs,

tons,

dollars

Defective product

manufacture

8 Processing

loss

Recycling losses due to passing

material back through the

process

Hrs,

tons,

dollars

Recycling defective

products

Definition & Example of different losses

27

Those losses have a close relationship with the production duration. Normally startup loss

occurs during the start up of the production. The different losses related to the production

time are presented graphically in below.

Fig 2.4: Eight Major Losses

2.5.3 Overall Equipment Effectiveness

To determine the overall Equipment Effectiveness we need to know about the different terminologies which are described step by step below.

1. Opening Hours

Number of hours on the calendar

=365D X 24H = 8,760 hours in a year

30D X 24H = 720 hours in a 30-day month

28

2. Working Hours

No of hours available for work

=Opening Hours — Production Adjustment — Periodic Servicing — Shut down

Maintenance

3. Operating time

=Working Hours – Shut down as a result of equipment – Process failures

4. Net Operating Times

=Standard Production Rate – Product rate reductions due to startup – Shutdown –

Change over

5. Valuable Operating Time

=Working Hours – wasted reprocessing – producing reject product

6. Availability

= X 100 (%)

Shutdown losses = shutdown maintenance loss + Production adjustment loss

Major stoppage loss = equipment failure loss + Production failure loss

7. Performance Rate

= X 100%

29

8. Quality Rate

Quality rate is expressed as the amount of acceptable product which equals to total

production less downgraded product, scrap, and reprocessed product as a percent of total

production.

Quality rate=

X100%

9. Overall plant Effectiveness (OEE)

= Availability x performance rate x Quality rate

2.5.4 Maximizing the effectiveness of production inputs To maximize the effectiveness of the production inputs we need to deploy the following

strategies…

1. Reducing raw material & Energy losses

2. Production costs and unit consumption

3. Control of unit consumption by production

4. Control of unit consumption by season

5. Control of unit consumption by product

6. Reducing Raw Material Losses

7. Preventing Raw Material Losses & saving Energy

8. Process Simplification

9. Reducing Maintenance Materials

10. Reducing work Losses

11. Reducing cleaning Losses

12. New control systems for personnel Reduction

13. Process centralization & Simplification

14. Reducing Distribution Losses

15. Reducing Administrative Losses

16. Reducing Testing & Inspection.

30

CHAPTER-3: OVERVIEW OF LSCL

OVERVIEW OF LSCL

3.1 Lafarge Surma Cement- At a glance

Lafarge Surma Cement (LSC), incorporated in January 2003 is the first multinational cement

manufacturer in the country with a fully integrated cement plant set up at a cost of US$

225mn at Sunamgong in the North East of the country. The company is promoted by Lafarge

of France and Cementos Molins the concrete & construction aggregates manufacturer in

Spain. The company commenced commercial production in October of 2006 and has a 10%

market share of the domestic cement market excluding its supply of clinker to other local

manufacturers.

Lafarge Surma Cement Limited‘s (LSC) integrated cement manufacturing plant has an

annual capacity of 1.5 million tonnes of grey cement and 1.15 million tonnes of clinker. The

Company extracts and processes the basic raw materials like limestone & shell from its own

quarry in Meghalaya, India. A 17km cross-border conveyor belt links the quarry with the

cement plant for transportation of raw materials. A separate 30 MW gas engine power

generation plant has been setup to supply uninterrupted power to the cement plant. The

company is now operating at full capacity after a court injunction in India resulted in a

temporary halt to the production of clinker in 2007. Legal proceedings are however ongoing

over a dispute over quarrying on forest land.

3.2 Process Description

The total manufacturing process is divided into 5 stages which are listed below from

upstream to downstream sequences…

1. Crushing System

2. Raw Grinding System

3. Burning System

4. Finish Grinding System

5. Packing & Dispatch System

31

3.2.1 Crushing System

The main raw materials used in Lafarge Surma Cement (LSC) for cement manufacturing

process are limestone, sand, shale, clay, and iron ore. The main material, limestone and shale

stone, is mined from their own quarry in Meghalaya, India.

Mining of limestone requires the use of drilling and blasting techniques. The blasting

techniques use the latest technology to insure vibration, dust, and noise emissions are kept at

a minimum. Blasting produces materials in a wide range of sizes from approximately 1-2

meters in diameter to small particles less than a few millimeters in diameter.

Material is loaded at the blasting face into trucks for transportation to the crushing plant.

Then the size of limestone is reduced using the primary & secondary crusher in India side.

And maximum size is 90-100mm which should not be more than more than 1% of the total

production. Then those raw materials are transferred to LSC plant located in Sunamgong by

the 17 km long cross boarder conveyor belt which capacity is 800 tph. The belt is operated

with 3 synchronizing motors among which two are located in Bangladesh side and another is

in the query side which is in India.

Fig 3.1: Raw material extraction & Crushing

3.2.2 Raw Grinding System

LSC has a vertical raw mill which is branded as ATOX 47.5 with RAR LVT 47.5 Separator

which is capable to produce 270 tpd dry powder raw meal at the fineness 90µm ( Max 12%

of the total production). Power requirement for the RAW Mill motor is 12.2Kwh/t where as

total requirement for the RAW Mill department is 24.6 Kwh/t.

Max. 1% on 90 – 100 mm

Silt Stone

Lime Stone

32

Fig 3.2: Vertical Raw Mill

The raw material for the RAW Mill feed is limestone, shale stone, sand & iron ore. Among

them limestone and shale comes from its own query in India and sand and iron ore are either

locally purchased or imported from India. The RAW Mill feed preparation are shown below.

Fig 3.3: Raw Mill feed preparation

33

Apron feeder and weigh feeder is most critical equipment here to achieve the quality product.

After the feed in the RAW mill the raw material are grinded into fine powder and transported

into Controlled Flow (CF) silo by the means of Separator and Air slides where the main

process parameter is differential pressure. The dry materials exiting mill are called "kiln

feed". The kiln feed is pneumatically blended to insure the chemical composition of the kiln

feed is well homogenized and then stored in silos until required.

From the CF Silo the raw meal is fed to Kiln where clinker the main constituent of cement is

produced.

3.2.3 Burning System

Burning system of LSC consists of Kiln with duplex burner, ESP, Coolax cooler, Pre-heater,

Calciner & Silo.

The raw meal is fed into Kiln from the CF silo with an uniformity index (KFUI) and then

undergoes a combination of physical / chemical process which includes drying of raw mix,

removal of water of crystallization, calcining of raw mix (expulsion of CO2), formation of

compounds, C2S, C3A, C4AF, Formation of C3S, nodulisation and cooling.

All those chemical & physical changes are occurs in the kiln where the raw meal are burned

form 100-1450°C. This results in a final black, nodular product known as "clinker" which has

the desired hydraulic properties.In LSC, kiln feed is fed to a preheater tower, which is about

150.0 meters. Material from the preheater tower is discharged to a rotary kiln which diameter

is 4.55 m and 58 meter long. The preheater tower and rotary kiln are made of steel and lined

with special refractory materials to protect it from the high process temperatures. The rotary

kiln is fired with an intense flame, produced by natural gas supplied from Jalalbad gas.

Preheater towers is also equipped with firing as well.

The rotary kiln discharges the red-hot clinker under the intense flame into a clinker cooler.

The clinker cooler recovers heat from the clinker and returns the heat to the pyroprocessing

system thus reducing fuel consumption and improving energy efficiency. Clinker leaving the

clinker cooler is at a temperature conducive to being handled on standard conveying

equipment.

34

Fig 3.4: Kiln Fig 3.5: Coolax Cooler

3.2.4 Finish Grinding System

The finish grinding section consists of 2 lines. Each line is having a Ball Mill (grinding),

Separator, Vent Fan, Separator fan & Silo. Clinker (94 - 97%) and Gypsum (3 -6%) is

grinded together to get Ordinary Portland Cement (OPC).

During the final stage of cement production, the clinker is ground with other materials (which

impart special characteristics to the finished product) into a fine powder. Up to 3-6% gypsum

is added to regulate the setting time of the cement. LSC also add some percentage of

limestone to prepare the composite limestone cement.LSC use hammer crusher to achieve a

preliminary size reduction of the clinker and gypsum. These materials are then sent through

ball (rotating, horizontal steel cylinders containing steel alloy balls) which performs the

remaining grinding. The grinding process occurs in a closed system with an air separator that

divides the cement particles according to size. Material that has not been completely ground

is sent through the system again for regrinding

35

Fig 3.6: Finish Grinding Process

3.2.5 Packing & Dispatch

The finish product is transferred using bucket elevators and conveyors to two large, storage

silos in the shipping department. There the cement is packed into 50 kg bags using three

rotary packers. Then the cement is distributed to the dealers and retailers by the means of

barges & trucks. LSC is having two barge loaders with the loading capacity of 3600 tpd.

3.3 Maintenance Department-LSC

World leader in building materials, Lafarge is now operating in 78 countries all over the

world and they structured their organization from the experience of 170 years of operation

which is almost same in all the plants. The prescribed organization structure is as below.

Lafarge Surma Cement is following the chart-1 with the splitting Electrical and

Instrumentation maintenance department in two separate departments which are electrical

maintenance department and Instrumentation maintenance department.

36

Fig 3.7: Organizational Structure

The six functions on the organization is based on are-

01. Management:

Organise and manage the department's human, financial and material resources to optimise

the quality of its services and its technical and economical performance

Ensure in the short, medium and long term the optimum equipment availability and

performance at minimum cost

02. Inspection:

Follow and measure equipment condition, analyse trends, and identify the needs for

maintenance (for mechanical/electrical/ mobile/instrumentation equipment and civil works),

taking into account production constraints

02. Planning:

Define the methodology, the manpower, the spares and the other resources necessary to

achieve efficient and safe maintenance in line with technical standards

37

04. Scheduling

Define the work program according to operational priorities, manpower, resources and

equipment availability

05. Execution:

Complete maintenance jobs with the highest level of quality, safety and effectiveness at

minimum cost to maximise equipment availability

Fig 3.8: Maintenance Function

06. Improvement:

Reduce maintenance repair work throughout equipment life cycle by upgrading materials and

practices to improve technical and economical performance

The maintenance department in LSC is as in the next pages…..

38

Fig 3.9: Organization Chart-Maintenance

Fig 3.10: Organization Chart- Mechanical Maintenance

39

Fig 3.11: Organization Chart-Methods

Fig 3.12: Organization Chart- Instrument & Control and Electrical maintenance

3.4 Maintenance Philosophy

Mainly the structure was defined in the basis of

Priority should be given to condition-based preventive maintenance;

An organisational structure based on 6 functions, three of which form the main pillars:

Inspection, Planning and Implementation;

Scheduling of tasks which call for co-ordination between the different departments

within the Works;

40

Willingness by all players to propose on-going Improvements to equipment and

practices, with results that can be measured in terms of cost and reliability, driven and

encouraged by the Management …continuously;

The development of common methods and tools (risk analysis, Best Practices, ADAP,

MAXIMO, Lafarge Codification) promoting capitalisation and making good use of

experience within the Division … to ensure progress is made more quickly.

The main goal of the maintenance department is to increase the availability of the plant

equipment as well as plant reliability. To achieve the best performance some criteria was

defined which are as below.

MTTR : Mean Time To Repair

MTBF : Mean Time Between Failure

OEE : Overall Equipment Effectiveness = Availability x Performance x Quality. Key

performance indicator in the TPM approach.

PG (Work Generated by Preventive Maintenance): maintenance based on

significant equipment condition parameters analysis using five senses and simple

measurement techniques. Examples: replacement of liners, replacement of V-belt, of

conveyor belts.

PD (Work Generated by Predictive Maintenance) : maintenance activities based

on significant equipment condition parameters analysis using advanced detection

techniques. Examples : replacement of bearings using vibration analysis, oil

replacement using oil analysis, tightening of bolts of bus bar using thermo graphic

inspection.

SOP : Standard Operating Procedure

But it was noticed that although having a structured maintenance organization LSC failed to

meet the set KPI (Key Performance Indicator). So it is essential to find the hole which is

responsible for the low performance.

3.5 Downtime and KPI in LSCL

3.5.1 Down Time Recording

In LSC (Lafarge Surma Cement) the stoppages are automatically logon through a software

named ADAP (Advance Downtime Analysis program), and then manually segregated into

different types. ADAP is connected to all the major drive of all process area i.e. Crusher,

41

LBC, VRM, Kiln, Cement Mill-1, and Cement Mill-2. When any of them tripped a stoppage

is logged on into ADAP automatically and ends when the equipment starts again. To

evaluate the stoppages in different stoppage category the following reliability definitions are

used throughout the thesis work.

Fig 3.13: ADAP

3.5.2 Operating Hours

For kiln, Operating hours as counted from feed starts to feed-off

Other equipment, hours of operation for system‘s main motor (ex: mill motor for

grinding system)

3.5.3 Hours of Stoppage

There are 3 types of stoppages in LSC which are Circumstantial stoppage, Scheduled stoppege and incidental stoppege.

42

3.5.3.1 Circumstantial stoppage hours

Stoppages due to external factors such as strikes, market, full inventories, etc. Events on

which the plant has no or limited control.

3.5.3.2 Scheduled stoppage hours

Actual stoppage as scheduled at budget preparation.

For a kiln, if the scheduled stoppage is moved up more than 15 days, the first 5 days are

considered as incident stoppages. If the stoppage is extended for technical reasons, the

excess time is also considered as an incident.

For other equipment such as mills, downtime is deemed scheduled when planned at least one

month in advance.

3.5.3.3 Incident stoppage hours

Defined as unscheduled stoppages due to electrical, mechanical, production, process, etc.

Events on which the plant can impact.

3.5.3.4 Other Type of Hours

Available Hour

Available hours in month of January=31 x 24 = 744 hours

Available hours in 2005= 365 x 24 = 8760 hours

3.5.3.5 Budgeted scheduled downtime

For a kiln, a stoppage is deemed scheduled when planned during preparation of the annual

budget. Budgeted scheduled downtime can cover downtime for technical (overhaul) or

economical (market, etc.) reasons.

For other equipment, the scheduling has to be made at least one month in advance.

3.5.4 Performance Indicators for LSC

3.5.4.1 Number of Incident Stoppages

Number of times the equipment is stopped for incident.

43

3.5.4.2 Reliability

For a given equipment, operating hours divided by (operating hours + hours for incident

stoppages).

RF = Operating hours / [Operating hours + Incident stoppage hours]

3.5.4.3 Utilization

For a given system, operating hours divided by available hours.

UF = operating hours / avalable hours

Table 3.1: Example of RF & UF calculation

Type of Hours year(a) year(b) Month

Available hours 8760 8760 720

Circumstance stoppage hour 24 48 80

Stoppage for scheduled downtime 672 672 16

Incident stoppage hours 168 144 6

Operating hours 7896 7896 618

Utilization (%) 0.901 0.901 0.858

Reliability (%) 0.979 0.982 0.99

3.5.4.4 Overall Plant Effectiveness

OEE = Availability x performance rate x Quality rate

= Reliability x Utilization Factor x Quality rate (In LSC term)

As the reliability is the same representative of the Availability in the Lafarge doctrine is used

for calculating the OEE. On the other hand as Lafarge doctrine use to calculate the UF and

this actually represents the performance of the equipment in terms of time ratio instead of

capacity ratio.

44

3.5.5 Classification of Downtime

All the stoppages logged on into the ADP has to be classified into different stoppages time as

described earlier. For different process stages the stoppages classification are descrived

below.

3.5.5.1 Crushing System

For calculating the reliability LSC use the equipment which represents the true state of

production. In LSC the primary crusher represents the true picture of the crushing system.

But unfortunately it experienced a major breakdown within the 1Q of the commissioning and

stored data are not the true representative, Hence this process stage is left out from our

analysis.

3.5.5.2 Raw grinding system

Separator, product adjustment.

Stoppage in order to adjust the separator for a product change, is considered a Scheduled

stoppage when performed on a regular basis.

Situation 1:

At 2 a.m., an incident occurred on the mill. Production was not required to meet kiln feed.

The corrective actions (duration 1 hour) were performed the following morning at 6 a.m.

Mill was put back into operation by 10 a.m.

Incident Stoppage hours: 1 hour

Circumstance stoppage hours: 7 hours (4 + 3)

If cooling and reheating periods were required before and after the corrective actions, it

should be part of the Incident Stoppage Hours.

3.5.5.3 Burning System

Situation 1:

45

Change of budget dates done for circumstance reasons: remains Scheduled or Circumstance.

Kiln shutdown initially beginning on March 1st for 21 days is moved to accommodate a

market change. Actual date is February 1st and it lasts for 21 days. The 15 day criteria does

not apply.

Stoppage for scheduled downtime: 21 days

Situation 2:

Scheduled shutdown is longer than expected for technical reasons like an unexpected

equipment damage or longer period of time required to perform the activity: the extra

duration is considered Incident stoppage.

Situation 3:

Shutdown is extended for circumstance reason: the extra duration is Circumstance stoppage

hours (the work is performed on one shift instead of two).

Situation 4:

Anticipating the market conditions, at budget time, the shutdown dates are scheduled.

Budgeted Scheduled Downtime should cover the required time to perform the work under

normal conditions. If conditions allow to stretch the duration of downtime by using less

overtime, etc., then the additional time is considered Circumstance stoppage hours.

Due to a weak market, the kiln is going to be down for 9 weeks. That opportunity is taken to

perform a major repair on the precipitator (critical path task). The kiln shutdown for repairs

lasts 5 weeks. Under good market condition, this would have taken 3 weeks using overtime

and contractors.

Stoppage for scheduled downtime: 504 hours (3 weeks)

Circumstance stoppage hours: 1008 hours (6 weeks)

Situation 5:

Duration of shutdown is shorter than budgeted: Scheduled Downtime duration is equal to

actual.

Situation 6:

Budgeted/actual stoppage date (15 day criteria)

May 1st is the budgeted stoppage date. Due to nose ring failure, actual date is April 1st. The

first 5 days are considered Incident Stoppage hours, the following days are Scheduled.

May 1st is the budgeted stoppage date. Due to nose ring failure, actual date is April 16th.

The total downtime is considered Scheduled Downtime.

46

May 1st is the budgeted stoppage date. Due to nose ring failure, actual date is April 13th.

The first 2 days are Incident Stoppage hours.

May 1st is the budgeted stoppage date. Actual scheduled down day is June 1st and lasts 15

days: total duration is considered Scheduled.

Situation 2:

2 weeks in advance a 16 hour kiln shutdown is scheduled to replace grates in the cooler, the

downtime is considered Incident Stoppage Hours.

3.5.5.4 Finish grinding system

Situation 1:

Type of incident, product adjustment

Stoppages in order to adjust the separator for a change of product is considered a Scheduled

Stoppage when done on a regular basis.

Situation 2:

At 11 p.m., an incident occurred on the mill. Production was not required to meet market

demand. The corrective actions (duration 3 hours) were performed the following morning at

8 a.m. The mill was back in production by 11 a.m.

Incident Stoppage hours: 3 hours

Circumstance stoppage hours: 9 hours

If a cooling and reheating period was required before and after the corrective actions, it

should be part of the Incident Stoppage Hours.

Situation 3:

A mill must be stopped due to cement quality problems, downtime is recorded as Incident.

3.5.5.5 Impact of an incident from one system to another

If an upstream incident caused the shutdown of a downstream system due to lack of

material or hot air, the downtime on the downstream system is deemed Incident

Stoppage Hours.

The raw mill is down for lack of material feed. A failure occurred on the quarry

crusher. The mill downtime is recorded as Incident Stoppage Hours except in the

case of a subcontracted quarry over which you have no control.

47

Hot clinker from the kiln must be diverted to the hot bin via an equipment which is

part of the mill system. Therefore, the mill has to be stopped. The mill was able to

run, but the shift foreman decided to divert the production to keep the kiln in

operation. Mill downtime is Circumstance Stoppage.

3.5.5.6 Power downtime

Power contract

If the power contract is such that a piece of equipment has to be down for a certain period of

time during the day or during the year, there are two possibilities in case of Stoppages:

a) no work is performed on the equipment (yard, maintenance. . . ), the downtime is a

Circumstance type.

b) the stoppage is used to perform some work, then it becomes Scheduled or Incident

downtime depending on the degree of Scheduling. Most of the time it should be considered

as Scheduled

A power stoppage occurs on a piece of equipment which belongs to the plant. It is an

Incident stoppage. If, however, the failure is due to an «Act of God», over which the plant

has no control, or is not expected to have protection from, it is a Circumstance.

Note: Each plant must develop an envelope of circumstances which would apply here.

Plant generates its own electricity

When the incident on a piece of equipment from one system (e.g. kiln or boiler) results in the

shutdown of another system (e.g. mill #1) to match the power generation, the downtime of

the last system (mill #1) is Circumstance Stoppage. The plant could have avoided the

situation by purchasing electricity for production.

However in the case of an incident on a piece of equipment due to a switch from plant power

station to the local electricity distributor, the event would be considered as an incident

stoppage.

48

CHAPTER-4: DATA COLLECTION

AND ANALYSIS DATA COLLECTION AND ANALYSIS

4.1 Data collection

All the stoppages are logged on in software named ADAP (Advanced Downtime Analysis

program). All these data are entered into the software automatically and the CCRO (Central

Control Room Operator) segregate the stoppages in the different types as per the guideline

described in chapter 3.Then the incidental stoppages are classified into the 4 different

subtypes. Subtypes are classified according the discipline i.e. Mechanical, Electrical,

Production and Others. The stoppages which are caused by Mechanical fault is denoted by

―M‖ and by ‗F‖, ―E‖ & ―O‖ which are caused by production, electrical and others reason

respectively. In most of the cases CCRO segregate the stoppages into their subtypes and

method manager validate them. Although LSC has an excellent system in-place to classify

the stoppages, it was noticed that most of the stoppages was not segregated properly to their

types and subtypes. To eliminate this problem a tool was developed as below and the CCRO

was educated on the stoppages classification guideline. The most important thing a guideline

was developed so that all the stoppages can be segregated effectively and scope was also

generated so that discipline heads can provide their feedback in the monthly reliability

meeting as well as any time within the month.

Table 4.1: Sample data analysis for proper allocation of different incidental stoppages

FINISH GRINDING SYSTEM (LINE- 1)

Total Stoppage Hrs Incident Planned Circumstance Description total hrs Frequenc

y total hrs

Frequency total hrs Freque

ncy CM-1 99.91 15 0 0 368.68 3

49

Incident Stoppage Hrs/Dept

total hrs

Frequency total days

Cement Loss (KT)

CM-1 mechanical 67.34 3 2.81 5.66

CM-1 electrical 10.65 7 0.44 0.89

CM-1 production 9.13 2 0.38 0.77 Others (Incident) 12.7

9 3 0.53 1.07 Not Considered 0 0 0.00 0.00 Total 99.9

1 15 4.16 8.39

Causes for Incident Stoppage

Apparent Causes Designation frequency

hours %

Clinker transport belt to hooper (402BC01) Belt torn out 2 55.4 55.4

Power failure/Dip (External) Gas engine maintenance 3 12.8 12.8

Power distribution site Insulation of 6.6 KV power line damage 2 5.97 6.0

Gypsum/Additive apron feeder (403AF01)

Input pinion of geared motor damage 1 12 12.0

Clinker weigh feeder (416WF02) Load cell replacement 2 1.77 1.8 Separator gearbox lubrication unit (416LU03) Low temperature 1 8.09 8.1

Separatoe fan (416FA04) RTD malfunctioning 1 1.64 1.6 Slide shoe bearing outlet lubrication unit (416LU02)

Cooling water LL level malfunctioning 1 1.04 1.0

Silo feed bucket elevator (418BE01) Belt sway 1 0.72 0.7

Mill Venting fan (416FA07) Damper Electrical feedback missing 1 0.56 0.6

Total 15 99.9 100.0

After evaluating all the stoppages in their right types and subtypes a study was carried out to

identify the incident which are most likely to be considered as avoidable my the means of

Autonomous Maintenance i.e. by implementing proper inspection, cleaning, restoring the

equipments in their original state and providing the proper training to the operators and

50

technician and all establishing the involvement of all departments i.e. maintenance,

production and process in maintaining the equipments. Collected data and actions where AM

are suggested are included in appendix A, B, C & D for different process systems.

4.2 Stoppages Analysis

4.2.1 Stoppages distribution by discipline For identifying the discipline strength, weakness in the system and better understanding of

the causes all the incidental stoppages were divided into the subtypes which are presented in

the figure 4.1. It was distributed as a percentage of stoppages hours caused by the particular

discipline to the total stoppages hours. It was also calculated after eliminating the stoppages

by the means of AM how they are distributed.

Fig 4.1: Distribution of stoppages by percentage among different discipline

4.2.2 Pareto Analysis

Pareto analysis is a statistical technique in decision making that is used for selection of a

limited number of tasks that produce significant overall effect. It uses the Pareto principle –

the idea that by doing 20% of work, 80% of the advantage of doing the entire job can be

generated

Pareto analysis is a formal technique useful where many possible courses of action are

competing for attention. In essence, the problem-solver estimates the benefit delivered by

each action, then selects a number of the most effective actions that deliver a total benefit

reasonably close to the maximal possible one.

Pareto analysis is a creative way of looking at causes of problems because it helps stimulate

thinking and organize thoughts. However, it can be limited by its exclusion of possibly

30%

27%

19%

24%

Stoppages before AM

CHSIM

CHSIE

CHSIF

CHSIO

29%

26%21%

24%

Stoppahes after AM

CHSIM

CHSIE

CHSIF

CHSIO

http://en.wikipedia.org/wiki/Statistics

http://en.wikipedia.org/wiki/Decision_making

http://en.wikipedia.org/wiki/Pareto_principle

51

important problems which may be small initially, but which grow with time. It should be

combined with other analytical tools such as failure mode and effects analysis and fault tree

analysis for example

4.2.2.1 Burning System

Table 4.2: Pareto Analysis of stoppages in Burning System

App. Causes Code

Cause Code Designation Hours % Frequ

ency % Average %

8 0 137.46 36.77 18 18.18 27.47 1 0 66.87 17.89 4 4.04 10.96 312SM01 0 9.56 2.56 19 19.19 10.88 316BP01 9 Refractory 28.41 7.6 1 1.01 4.3 313XY01 0 3.26 0.87 7 7.07 3.97 317CC01 3 Plugging 17.33 4.63 3 3.03 3.83 5 0 5.4 1.45 6 6.06 3.75 26 0 12.11 3.24 4 4.04 3.64 317CC01 4 Snowmen 18.57 4.97 2 2.02 3.49 314FA01 7 Bearings 21.63 5.79 1 1.01 3.4 314FA01 6 Motor 7.04 1.88 4 4.04 2.96 313CA01 5 Sensors / Instrumentation 2.74 0.73 5 5.05 2.89 312XY01 0 2.48 0.66 5 5.05 2.86 312BE01 4 Sensors / Instrumentation 4.6 1.23 4 4.04 2.63

317CR01 4 Internals (Hammers, Jaws, Cone…) 14.84 3.97 1 1.01 2.49

317CC01 0 6.61 1.77 3 3.03 2.4 6 0 1 0.27 4 4.04 2.15 317CR01 8 Overloading 12.16 3.25 1 1.01 2.13 316DR02 12 Vibrations 0.6 0.16 4 4.04 2.1 312FA07 7 Bearings 1.22 0.33 3 3.03 1.68

Fig 4.2: Pareto Analysis for Burning System

0

5

10

15

20

25

30

8 1

312

SM0

1

316B

P01

313

XY0

1

317

CC

01

5

26

317C

C01

314F

A01

314F

A01

313C

A01

312

XY0

1

312B

E01

317

CR

01

317

CC

01

6

317

CR

01

316

DR

02

312F

A07

%

Apparent Causes

http://en.wikipedia.org/wiki/Failure_mode_and_effects_analysis

http://en.wikipedia.org/wiki/Fault_tree_analysis



52

4.2.2.2 Raw Grinding System

Table 4.3: Pareto Analysis of stoppages in Burning System

App. Causes Code

Cause Code

Designation Hours % Frequency % Average %

216FE04 0 127.19 19.25 40 11.83 15.54 216VV01 0 23.62 3.57 40 11.83 7.7 216SP01 4 Casing 93.46 14.14 2 0.59 7.37 216HO02 0 38.52 5.83 25 7.4 6.61 5 0 32.2 4.87 25 7.4 6.13 8 0 50.43 7.63 10 2.96 5.3 216BC02 1 Alignment 12.56 1.9 24 7.1 4.5 216PU01 0 32.39 4.9 11 3.25 4.08 19 0 39.22 5.93 6 1.78 3.86 212QR01 0 19.17 2.9 9 2.66 2.78

216BE01 4 Sensors / Instrumentation 8.78 1.33 13 3.85 2.59

216WF02 7 Drum assembly 24.72 3.74 3 0.89 2.31 212BC05 3 Plugging 14.93 2.26 6 1.78 2.02 212QR02 0 6.63 1 10 2.96 1.98 216WF02 3 Plugging 8.03 1.22 9 2.66 1.94 216WF02 0 8.01 1.21 9 2.66 1.94 216BE01 3 Plugging 14.85 2.25 5 1.48 1.86

216LU04 3 Sensors / Instrumentation 4.73 0.72 9 2.66 1.69

216FA05 0 19.68 2.98 1 0.3 1.64 9 0 3.81 0.58 7 2.07 1.32 216HO01 0 7.29 1.1 5 1.48 1.29 212BC04 3 Plugging 7.12 1.08 5 1.48 1.28

216MV01 6 Sensors / Instrumentation 5.1 0.77 5 1.48 1.13

216BC02 5 Slippage 3.1 0.47 6 1.78 1.12 216WF02 2 Belt 8.21 1.24 3 0.89 1.06 212DG02 5 Chain / Links 6.03 0.91 4 1.18 1.05 216MV01 0 3.25 0.49 5 1.48 0.99 216MV01 12 Overloading 3.01 0.46 5 1.48 0.97

216LU01 3 Sensors / Instrumentation 2.91 0.44 5 1.48 0.96

216FA05 8 Temperature 2.87 0.43 5 1.48 0.96 216DR01 0 2.11 0.32 5 1.48 0.9

216FA05 2 Sensors / Instrumentation 5.97 0.9 3 0.89 0.9

212HO01 0 3.73 0.56 4 1.18 0.87 216AW01 0 5.61 0.85 3 0.89 0.87

216BC02 4 Sensors / Instrumentation 3.6 0.55 4 1.18 0.86

216LU03 8 Oil / Grease 3.15 0.48 4 1.18 0.83 216WF01 11 Transmission 4.82 0.73 3 0.89 0.81

53

Fig 4.3: Pareto Analysis for Raw Grinding System

4.2.2.3 Finish Grinding System (Line-1)

Table 4.4: Pareto Analysis of stoppages in Finish Grinding System (line-1)

App. Causes Code

Cause Code


5 0 65.73 8.28 27 11.44 9.86 403CR01 0 67.08 8.45 4 1.69 5.07 416LU02 6 Filter 52.73 6.64 8 3.39 5.01 416LU02 8 Oil / Grease 48.14 6.06 8 3.39 4.73 403CR01 8 Overloading 54.09 6.81 6 2.54 4.68 402BC01 6 Belt assembly 55.36 6.97 2 0.85 3.91

416MB01 10 Rings, Slide shoe bearings 23.04 2.9 11 4.66 3.78

416MB01 11 Bearing temperature 19.8 2.49 11 4.66 3.58 418VV01 0 22.74 2.86 10 4.24 3.55 416HO03 0 26.78 3.37 7 2.97 3.17 416WF01 5 Sensors / Instrumentation 26.49 3.34 7 2.97 3.15 416FA07 12 Damper 15.59 1.96 8 3.39 2.68 416LU02 10 Pump 17.73 2.23 6 2.54 2.39 416WF02 3 Plugging 22.61 2.85 4 1.69 2.27 416FA02 2 Sensors / Instrumentation 15.46 1.95 6 2.54 2.24 26 0 9.26 1.17 6 2.54 1.85 416VN03 0 8.84 1.11 6 2.54 1.83 416LU01 1 Automation 8.81 1.11 6 2.54 1.83 921CM04 0 24.55 3.09 1 0.42 1.76 416DC02 4 Sensors / Instrumentation 10.66 1.34 5 2.12 1.73 416WF01 3 Plugging 3.83 0.48 7 2.97 1.72 403AF01 10 Motor 21.42 2.7 1 0.42 1.56 416LU01 3 Sensors / Instrumentation 3.51 0.44 6 2.54 1.49

0

2

4

6

8

10

12

14

16

18%

Apparent Causes

54

App. Causes Code

Cause Code


418AS03 0 9.86 1.24 4 1.69 1.47 19 0 8.47 1.07 4 1.69 1.38 9 0 6.46 0.81 4 1.69 1.25

416LU02 7 Leakage (Gasket, Bolting…) 12.87 1.62 2 0.85 1.23

0 0 4.53 0.57 4 1.69 1.13 416SP01 3 Sensors / Instrumentation 7.38 0.93 3 1.27 1.1 416DC02 1 Automation 5.96 0.75 3 1.27 1.01 428VV01 0 2.35 0.3 4 1.69 1 403AF01 12 Reducer 11.98 1.51 1 0.42 0.97 921CM04 8 Motor 11.76 1.48 1 0.42 0.95 416SC02 2 Plugging 4.49 0.56 3 1.27 0.92 426DC02 6 Bags 11.16 1.4 1 0.42 0.91 416DR01 5 Gearbox lubrication 4.34 0.55 3 1.27 0.91 416LU02 0 3.96 0.5 3 1.27 0.88 416HO02 0 7.13 0.9 2 0.85 0.87 416SP01 2 Plugging 3.17 0.4 3 1.27 0.84 416AW01 0 3.16 0.4 3 1.27 0.83 416FA02 0 6.39 0.8 2 0.85 0.83 416VV03 0 3.02 0.38 3 1.27 0.83 416DC01 2 Plugging 9.36 1.18 1 0.42 0.8 418AS03 3 Plugging 2.4 0.3 3 1.27 0.79 416WF01 4 Calibration 5.56 0.7 2 0.85 0.77 416WF02 5 Sensors / Instrumentation 2.19 0.28 3 1.27 0.77 416LU01 0 2.17 0.27 3 1.27 0.77 416LU01 10 Pump 2.04 0.26 3 1.27 0.76 416LU02 3 Sensors / Instrumentation 1.94 0.24 3 1.27 0.76 416LU03 4 Heat exchanger 8.09 1.02 1 0.42 0.72 402VV02 0 7.9 0.99 1 0.42 0.71

Fig 4.4: Pareto Analysis for Finish Grinding System (Line-1)

0

2

4

6

8

10

12

5

416L

U0

2

403C

R01

416M

B0

1

41

8VV

01

416

WF0

1

416L

U0

2

416F

A02

41

6VN

03

921

CM

04

416

WF0

1

416L

U0

1

19

416L

U0

2

41

6SP

01

42

8VV

01

921

CM

04

426D

C02

416L

U02

41

6SP

01

416F

A02

416

DC

01

416

WF0

1

416L

U0

1

416L

U0

2

40

2VV

02

%

Apparent Causes

55

4.2.2.4 Finish Grinding System (Line-2)

Table 4.5: Pareto Analysis of stoppages in Finish Grinding System (line-2)

App. Causes Code

Cause Code


5 0 46.38 5.56 22 11.6 8.57 428VV01 0 37.59 4.5 15 7.89 6.2 403CR01 0 62.59 7.5 6 3.16 5.33 403CR01 8 Overloading 55.87 6.69 6 3.16 4.92 426DC02 2 Plugging 27.23 3.26 8 4.21 3.74 426WF01 5 Sensors / Instrumentation 37.59 4.5 4 2.11 3.3 402BC01 6 Belt assembly 45.99 5.51 1 0.53 3.02 9 0 19.34 2.32 7 3.68 3 19 0 17.67 2.12 7 3.68 2.9 426MB01 0 23.27 2.79 5 2.63 2.71 402BC01 0 37.22 4.46 1 0.53 2.49 426LU02 8 Oil / Grease 8.78 1.05 7 3.68 2.37 426DC02 6 Bags 27.35 3.28 2 1.05 2.16 426DR01 3 Sensors / Instrumentation 13.58 1.63 5 2.63 2.13

426DC02 5 Leakage (Gasket, Bolting…) 15.54 1.86 4 2.11 1.98

426DR01 5 Gearbox lubrication 14.02 1.68 4 2.11 1.89 426WF01 4 Calibration 17.56 2.1 3 1.58 1.84 426HO03 0 12.16 1.46 4 2.11 1.78 426FA04 13 Vibrations 23.47 2.81 1 0.53 1.67 26 0 5.66 0.68 5 2.63 1.65 403AF01 10 Motor 22.68 2.72 1 0.53 1.62 426MB01 11 Bearing temperature 9.35 1.12 4 2.11 1.61 428BE01 0 13.73 1.64 3 1.58 1.61 426DC02 0 8.66 1.04 4 2.11 1.57 426DR01 7 Motor 11.43 1.37 3 1.58 1.47 426FA04 0 19.71 2.36 1 0.53 1.44 426MB01 12 Mill shell, Doors 17.24 2.07 1 0.53 1.3 426BE01 13 Overloading 8.43 1.01 3 1.58 1.29 428BE01 1 Alignment 7.62 0.91 3 1.58 1.25 420DH03 0 2.73 0.33 4 2.11 1.22 416DR01 7 Motor 5.62 0.67 3 1.58 1.13 921CM04 8 Motor 12.63 1.51 1 0.53 1.02 426LU03 8 Oil / Grease 3.63 0.44 3 1.58 1.01 426FA04 2 Sensors / Instrumentation 3.6 0.43 3 1.58 1 426DR01 10 Bearings 3.34 0.4 3 1.58 0.99 402BC02 3 Plugging 11.54 1.38 1 0.53 0.95 426DC02 4 Sensors / Instrumentation 2.55 0.31 3 1.58 0.94 403BC03 3 Plugging 11.15 1.33 1 0.53 0.93 418FA07 0 11.08 1.33 1 0.53 0.93 426VV03 0 1.77 0.21 3 1.58 0.9 428BE01 4 Sensors / Instrumentation 5.85 0.7 2 1.05 0.88 403AF01 3 Plugging 5.18 0.62 2 1.05 0.84 402VV02 0 9.51 1.14 1 0.53 0.83 426SM01 0 4.83 0.58 2 1.05 0.82 402PA01 0 8.71 1.04 1 0.53 0.78

56

App. Causes Code

Cause Code


6 0 4.25 0.51 2 1.05 0.78 402PA01 0 8.32 1 1 0.53 0.76 402FV06 0 3.83 0.46 2 1.05 0.76 403AF01 5 Slippage 8.04 0.96 1 0.53 0.74 426DC02 8 Cleaning system 7.98 0.96 1 0.53 0.74 426RA08 2 Plugging 3.44 0.41 2 1.05 0.73 418AS01 3 Plugging 7.74 0.93 1 0.53 0.73 426LU03 6 Filter 3.31 0.4 2 1.05 0.72 426LU04 8 Oil / Grease 3.09 0.37 2 1.05 0.71 403CR01 3 Casing 7.12 0.85 1 0.53 0.69 403BC01 0 6.36 0.76 1 0.53 0.64

Fig 4.5: Pareto Analysis for Finish Grinding System (Line-2)

0

1

2

3

4

5

6

7

8

9

5

403C

R01

402B

C01

426M

B01

426D

C02

426D

R01

426F

A04

426M

B01

426D

R01

426B

E01

416D

R01

426F

A04

426D

C02

426V

V03

402V

V02

6

403A

F01

418A

S01

403C

R01

%

Apparent Causes

57

4.2.3 Root Cause Analysis (RCA)

Root cause analysis (RCA) is a class of problem solving methods aimed at identifying the

root causes of problems or events. The practice of RCA is predicated on the belief that

problems are best solved by attempting to address, correct or eliminate root causes, as

opposed to merely addressing the immediately obvious symptoms. By directing corrective

measures at root causes, it is more probable that problem recurrence will be prevented.

Causes of all the data collected is not readily identified on site. The apparent cause i.e the

equipment which is responsible for the particular incident can by identified easily, but the

underlying cause is often stayed hidden and for better management of the down time it is

essential to identify all of them. In LSC RCA is used to identify those all possible root causes

using APPOLP RCA methodology. Basically RCA was conducted for the causes identified

by Pareto analysis.

Here is an example (part of RCA conducted for the incident of Kiln stoppages due to

313FA01

http://en.wikipedia.org/wiki/Problem_solving

http://en.wikipedia.org/wiki/Root_cause

58

Fig 4.6: RCA Sample (Flow diagram)

59

4.3 Effect of AM on Reliability


Opening hour (year 2008)

Number of total days in 2008 is 366

So, Opening hour in 2008 = 366X24 = 8784 hours

Cummulitative hours of stoppages in 2008 is 402.81 hrs


= Hours Worked / [Hours Worked + Incident stoppage hours]

RF= 8784/ (8784+402.81)

= 95.03 %

UF = Operating hours / Avialable hours

= Working Hours/ Opening Hours

= 7704.38/8784

=87.71%

After proposed AM

Cummulitative hours of stoppages in 2008 after AM is202.27 hrs

RF= 8784/ (8784+202.27)

= 97.51 %

UF = 7904.9/8784

=89.99%






60



RF= 8784/ (8784+774.56)

= 89.97 %



= 6944.43/8784

=79.06%

After proposed AM

Cummulitative hours of stoppages in 2008 after AM is 334.07 hrs

RF= 8784/ (8784+334.07)

= 95.67 %

UF = 7384.92/8784

= 84.07%

4.3.3 Finish Grinding System (Line-1)







RF= 8784/ (8784+928.21)

= 81.23 %



= 4018.14/8784

=45.74%

61

After proposed AM


RF= 8784/ (8784+298.79)

= 93.96 %

UF = 4647.56/8784

= 52.91%








RF= 8784/ (8784+937.13)

= 84.67 %



= 5174.43/8784

=58.91%

After proposed AM


RF= 8784/ (8784+349.92)

= 94.27 %

UF = 5761.65/8784

= 65.59%

62

4.4 Effect of AM on OEE


Rated capacity of the kiln= 3600 tpd

Total production in year 2008 = 1371762 ton

Actual Average Output=3438 tpd

Performance Rate

= X 100%

= (3438/3600) X 100%

=95.05%

Overall Equipment Efficiency


= Reliability x performance rate x Quality rate (In LSC term)

=95.03%X95.50%X1

=.91

Note: (As rejection rate for quality problem is almost zero quality rate is considered 1)

After proposed AM


=97.51%X95.50%X1

=.93


Rated capacity of the kiln= 278 tph


Actual Average Output=246 tph

Performance Rate

63

= X 100%

= (246/278) X 100%

=88.49%




=89.97%X88.49%X1

=.80

Note: (As rejection rate for quality problem is almost zero quality rate is considered as

1.

After proposed AM


=95.67%X88.49%X1

=.85





Performance Rate

= X 100%

= (85/120) X 100%

=70.83%



64


=81.23%70.83%X1

=.58


1)

After proposed AM


=93.96%X70.83%X1

=.67





Performance Rate

= X 100%

= (100/120) X 100%

=83.33%




=84.67%X83.33%X1

=.71


1)

After proposed AM


=94.27%X83.33%X1

=.79

65

CHAPTER-5: RESULTS AND DISCUSSIONULTS AND DISCUSSION

RESULTS AND DISCUSSION 5.1 Results

Table 5.1: Present status of plant performance and effect of AM

Present Status After proposed AM

Kiln VRM CM1 CM2 Kiln VRM CM1 CM2 OEE 0.91 0.80 0.58 0.71 0.93 0.85 0.67 0.79

PF (%) 95.50 88.49 70.83 83.33 95.50 88.49 70.83 83.33

RF (%) 95.03 89.97 81.23 84.67 97.51 95.67 93.96 94.27

UF (%) 87.71 79.06 45.74 58.91 89.99 84.07 52.91 65.59

OH (Hrs) 8784 8784 8784 8784 8784 8784 8784 8784

HW (Hrs) 7704.36 6944.43 4018.14 5174.43 7904.9 7384.92 4647.56 5761.65

Output (Tph) 3438 246 85 100 3438 246 85 100

Rated Capacity (Tph) 3600 278 120 120 3600 278 120 120

CHS (hrs) 1079.64 1839.57 4765.86 3609.57 879.1 1399.08 4136.44 3022.35

NS (nos) 194 518 398 333 106 247 232 215

CHSI (hrs) 402.81 774.56 928.21 937.13 202.27 334.07 298.79 349.92

CHSP (hrs) 611.98 704.88 236.88 200.71 611.98 704.88 236.88 200.71

CHSC (hrs) 64.85 360.13 3600.77 2471.72 64.85 360.13 3600.77 2471.72

NSFI (Nos) 147 435 295 238 58 172 143 140

NSFP (Nos) 37 16 13 12 37 16 13 12

NSFC (Nos) 11 59 76 63 11 59 76 63

CHSIM (%) 44.88 48.3 27.75 39.65 39.69 58.68 32.24 25.11

CHSIE (%) 13.12 23.06 32.74 32.23 11.56 29.30 42.20 52.77

CHSIF (%) 38 28.64 39.51 28.12 45.65 12.02 25.50 22.07

CHSIO (%) 4.00 0.00 0.00 0.00 3.10 0 0 0

NSFIM (Nos) 24 124 83 63 8 39 43 24

NSFIE (Nos) 69 132 137 107 23 90 74 79

NSFIP (Nos) 45 179 75 68 18 43 26 37

NSFIO (Nos) 9 0 0 0 9 0 0 0

66

The result shows that performance of the plant is not meeting the group standard which is

98% in terms of reliability.

Above table represents all the calculations for OEE for the different process systems. It

shows the different types of stoppages and their duration. It also shows the subtypes of

the incidental stoppages with duration and frequency. This table also represents the rated

production capacity for each section and as well achieved rate and ultimately the

performance rate.

5.2 Discussion

From the analysis and calculation it found that the performance of the plant is not meeting

the group standard which is 98% in terms of reliability. These triggered to the

requirement of better management of all the equipment as well as the plant. As LSCL is a

cement manufacturing company which raw material is shale, sand , iron ore, limestone ,

gypsum etc. it is a real challenge to achieve the cleaning standard and maintain the basic

equipment condition without having the underneath goal of those. A better team effort is

the key to be successful in achieving the target by implementing AM. Management also

needs to pay more concern for managing the stoppages in better way and addressing the

recurrence stoppages.

Fig 5.1: Present status of plant RF and effect of AM

Kiln VRM CM1 CM2

Before 95.03 89.97 81.23 84.67

After AM 97.51 95.67 93.96 94.27

0

20

40

60

80

100

120

%

RF for Diiferent Process System

67

The figure shows the effect of AM on the reliability factor. It shows that the reliability factors

for the burning systems can be increased with out putting to much effort but implementing

the AM by 2.48% i.e the down time can be reduced by 200.54 hours. This also increase the

reliability factor of the Raw Grinding Systems, Finish Grinding System (Line-1) & Line 2 by

5.7%, 12.73% and 9.6% respectively which are equivalent to reducing the downtime by

440.49 hrs, 629.42 hrs and 587.21 hrs respectively.

Fig 5.2: Present status of plant OEE and effect of AM

The figure 5.2 shows the effect of AM on the Overall Plant Effectiveness. It shows that OEE

for the burning systems can be increased with out putting to much effort but implementing

the AM by 0.02 and by .05, 0.09 and 0.08 for the process stages Raw Grinding Systems,

Finish Grinding System (Line-1) & Finish Grinding (Line 2) respectively.

The analysis also revealed that competency of the present staffs is quite impressive to meet

the requirement for better management of the stoppages but need specific training on this

particular issue. The management level also need to provide more emphasis so that all the

data are managed in the proper way otherwise the reliability of the data will be questionable.

And wit out reliable data any sort of analysis will present a false impression. So all the

relevant staffs need to achieve better understanding of the stoppage guideline and ADAP.

CHSIM CHSIE CHSIF CHSIO

Before 0.91 0.80 0.58 0.71

After AM 0.93 0.85 0.67 0.79

0.000.100.200.300.400.500.600.700.800.901.00

OEE of different process systems

68

From the analysis result it is highly recommended to implement the Autonomous

Maintenance involving all the respective discipline. For implementing the AM following

steps are recommended which will well adjust with the existing LSCL organization.

Perform Initial Cleaning

The goal of the initial cleaning should include

o Eliminate dust and dirt from main body of equipment

o Expose irregularities such as slight defects, contamination sources,

inaccessible places,

o Sources of quality defects

o Eliminate unnecessary and seldom-used items, and simplify equipment

Address contamination source and inaccessible places

The goal of the addressing contamination source and inaccessible places is to reduce

housekeeping time by eliminating, sources of dust and dirt, preventing scatter, and improving

parts that are hard to clean, check, lubricate, tighten, or manipulate

Establish cleaning and checking standard

The activities for this step includes

o Formulate work standards that help maintain cleaning, lubricating, and

tightening levels with minimal time and effort

o Improve the efficiency of checking work introducing visual controls

Conduct general equipment inspection


o Provide inspection skills training based on inspection manuals

o Get individual equipment items into peak condition by subjecting them to

general inspection

o Modify equipment to facilitate checking. Make extensive use of visual

controls

Perform general process inspection


o Provide instruction in process performance, operation, and adjustment and in

methods of handling abnormalities in order to improve operational reliability

by developing process competent operators

69

o Prevent inspection duplications and omissions by incorporating provisional

cleaning and inspection standards for individual equipment items into periodic

inspection and replacement standards for entire processes or systems

Systematic autonomous maintenance


o Achieve quality maintenance and safety by establishing clear procedures and

standards for dependable autonomous maintenance

o Improve setup procedures and reduce work-in-process

o Establish a system of self-management for workplace flow, spares, tools,

work-in-process, final products, data, et

Practice full self-management


o Evolve activities and standardize improvements in line with company and

plant policies and objectives, and reduce costs by eliminating workplace waste

o Improve equipment further by keeping accurate maintenance records (e.q.,

MTBF) and analyzing the data in them

For implementing the steps 3, 4 and 5 some generic standard are presented in below…

Table 6.1: Checkpoints for Nuts and Bolts

Slight Defects

Are any nuts or bolts loose?

Are any nuts or bolts missing?

Bolt Lengths Do all bolts protrude from nuts by 2-3 thread length

Washers

Are flat washers used on long holes?

Are tapered washers used on angle bars and channels?

Are spring washers used where parts are subject to vibration?

Are identical washers used on identical parts?

Attachment of

Nuts and Bolts

Are bolts inserted from bottom, and visible from the outside?

Are devices such as limit switches secured by at least two bolts?

Are wing nuts on the right way around?

70

Table 6.2: Checkpoints for Electrical Equipments

Control

Panels

Are the interiors of distribution boards, switchboards, and control

panels kept clean, tidy, and well-organized by the application of the

5S principles?

Have any extraneous objects or flammable materials been left

inside?

Is the wiring inside control panels in good condition?

Are any wires coiled or trailing?

Are all ammeters and voltmeters operating correctly and clearly

marked?

Are any instruments or display lamps broken? Are any bulbs

faulty?

Are any switches broken? Do all switches work correctly?

Are control panel doors in good condition? Do they open and close

easily?

Are there any unused holes? Are control panels waterproof and

dustproof?

Electrical

Equipment

Are all motors free of overheating, vibration, and unusual noise and

smells?

Are all motor cooling fans and fins clean?

Are any attachment bolts loose? Are pedestals free of cracks and

other damage?

Sensors Are all limit switches clean and free of excessive play?

Are the interiors of all limit switches clean?

Are any wires trailing? Are all covers in good condition?

Are any limit switches incorrectly installed?

Are any limit switch dogs worn, deformed, or the wrong shape?

Are all photoelectric switches and proximity switches clean and

free of excessive play?

Are any sensors out of position? Are correct positions clearly

indicated?

Are all lead wires unchafed, and is insulation intact at entry points?

71

Switches Are all manual switches clean, undamaged, and free of excessive

play?

Are all switches installed in the correct position?

Are emergency stop switches installed in appropriate locations, and

are they working correctly?

Piping and

Wiring

Are any pipes, wires, or power leads loose or unsecured?

Are any ground wires damaged or disconnected?

Are any pipes corroded or damaged? Are there any bare wires or

wires with damaged insulation?

Are any wires coiled on the floor or dangling overhead?

Table 6.3: Checkpoints for Hydraulic Equipments

Hydraulic

Units

Is the correct quantity of fluid in hydraulic reservoirs, and is the

correct level indicated?

Is fluid at the correct temperature? Are the maximum and minimum

permissible temperatures indicated?

Is fluid cloudy (indicating air entrainment)?

Are all fluid inlets and strainers clean?

Are any suction filters blocked?

Are any fluid reservoir breather filters blocked?

Are all fluid pumps operating normally without any unusual noise

or vibration?

Are hydraulic pressures correct, and are operating ranges clearly

displayed?

Heat

Exchangers

Is any fluid or water leaking from fluid coolers or pipes?

Are temperature differences between fluid and water inlets and

outlets correct?

Are any tubes blocked?

Hydraulic

Equipment

Are there any fluid leaks?

Are hydraulic devices properly secured without any makeshift

fastenings?

72

Are hydraulic devices operating correctly without speed losses or

breathing?

Are hydraulic pressures correct, and are all pressure gauges

working correctly (zero points, deflection) ?

Piping and

Wiring

Are all pipes and hoses securely attached?

Are there any fluid leaks?

Are any hoses cracked or damaged?

Are all valves operating correctly?

It is easy to see whether valves are open or shut?

Are any pipes, wires, or valves unnecessary?

Table 6.4: Checkpoints for Pneumatic Equipments

FRLs Are FRLs always kept clean?

Is it easy to see inside them?

Are they fitted the right way around?

Is there sufficient oil, and are the drains clear?

Is the oil drip rate correct (approximately 1 drop for every 10

strokes)?

Are FRLs installed no more than 3m from the pneumatic

equipment?

Are pressures adjusted to the correct value and are operating ranges

clearly indicated?

Pneumatic

Equipment

Is any compressed air leaking from pneumatic cylinders or solenoid

valves?

Are all pneumatic cylinders and solenoid valves firmly attached?

Are any makeshift fixings in use (wire, adhesive tape, etc.)?

Is speed controllers installed the right way around?

Is there any abnormal noise or overheating of solenoid valves, and

are any lead wires chafed or trailing?

73

Piping and

Wiring

Are there any places in pneumatic pipes or hoses where fluid is

liable to collect?

Are all pipes and hoses clipped firmly into place?

Are there any compressed-air leaks?

Are any hoses cracked or damaged?


Is it easy to see whether valves are open or closed?

Are any pipes, wires, or valves unnecessary?

Table 6.5: Checkpoints for Transmission

V-belts and

Pulleys

Are any belts cracked, swollen, worn, or contaminated by oil or

grease?

Are any belts twisted or missing?

Are any belts stretched or slack?

Are multiple belts under uniform tension and all of the same type?

Are top surfaces of belts protruding above the pulley rims?

Are the bottoms of any pulley grooves shiny (indicating a worn belt

or pulley)?

Are pulleys correctly aligned?

Roller Chains Are any chains stretched (indicating worn pins or bushings)?

Are any sprocket teeth worn, missing, or damaged?

Is lubrication between pins and bushings sufficient?

Are sprockets correctly aligned?

Shafts,

Bearings, and

Couplings

Is there any overheating, vibration, or abnormal noise due to

excessive play or poor lubrication?

Are any keys or set bolts loose or missing?

Are any couplings misaligned or wobbly?

Are any coupling seals worn? Are any bolts slack?

Gears Are gears properly lubricated with the right amount of lubricant?

Are the surroundings clean?

Are any teeth worn, missing, damaged, or jammed?

Is there any unusual noise or vibration?

74

Table 6.6: Lubrication Checkpoints

Lubricant

Storage

Are lubricant stores always kept clean, tidy, and well-organized by

thorough application of the 5S principles? *

Are lubricant containers always capped?

Are lubricant types clearly indicated and is proper stock control

practiced?

Lubricant

Inlets

Are grease nipples, speed-reducer lubricant ports, and other

lubricant inlets always kept clean?

Are lubricant inlets dust proofed?

Are lubricant inlets labeled with the correct type and quantity of

lubricant?

Oil-level

Gauges

Are oil-level gauges and lubricators always kept clean, and are oil

levels easy to see?

Is the correct oil level clearly marked?

Is equipment free of oil leaks, and are oil pipes and breathers

unobstructed?

Automatic

Lubricating

Devices

Are automatic lubricating devices operating correctly and supplying

the right amount of lubricant?

Are any oil or grease pipes blocked, crushed or split?

Lubrication

Condition

Are rotating parts, sliding parts, and transmissions (e.g. chains)

always clean and well-oiled?

Are the surroundings free of contamination by excess lubricant?

Table 6.7: Checkpoints for General-Purpose Equipment

Pumps Are pumps and their stands free of unusual noise, vibration,

and play?

Are pedestal bolts tight, corrosion-free, and undamaged?

Are stands and pedestals free of corrosion, cracking, and other

damage?

Is any liquid leaking or spraying from gland packings?

75

Is any liquid leaking or spraying from pipes or valves?

Are any pipes or valves blocked?

Are all pressure gauges, vacuum gauges, flow meters,

thermometers, and other measuring instruments working

properly and marked with the correct operating ranges?

Are starting current and operating current values correct? Are

these clearly indicated?


Is it easy to see whether valves are open or closed?

Fans Are fans and their stands free of unusual noise, vibration, and

play?

Are all pedestal bolts tight, corrosion-free, and undamaged?

Are all stands and pedestals free of corrosion, cracking, and

other damage?

Are any gland packings leaking air or gas?

Are any ducts or dampers leaking air or gas?

Are any ducts blocked or clogged?

Are all pressure gauges, vacuum gauges, flow meters,

thermometers, and other measuring instruments working

properly and marked with the correct operating ranges?

Are starting current and operating current values correct? Are

these clearly indicated?

Are all dampers operating correctly?

Is it easy to see whether dampers are opened or closed?

A general guideline was also produce to eliminate the conflict among the different

departments. It is always subjected to the review of the HODs and need their approval and

recommended to implement in daily activities.

76

Fig 6.1: Distribution of maintenance activities within the discipline

77

CHAPTER-6: CONCLUSION AND

RECOMMENDATION CONCLUSION AND RECOMMENDATION

6.1 Conclusion Demand for high quality products at a reasonable cost is driving most of the manufacturers

worldwide to embrace equipment management programs like TPM. As can be seen from the

case study, TPM/AM has significantly: (1) reduced the yield loss, (2) reduced the downtime

of equipment, and (3) reduced the cost of operations and improved profitability. There is no

doubt that TPM/AM provides tremendous competitive edge to the manufacturers.

If we consider the case of Lafarge we will find that there is huge improvement in the

reliability i.e. availability of the equipment but little improvement in the overall plant

efficiency especially for both the cement mills. The reason behind this is, Lafarge don‘t

consider equipment performance as a business unit KPI (key performance indicators) rather

than only considered as a production team‘s KPI. Rather than they give more emphasis on the

utilization factor which also subjected to the better plan. For the year of 2008 utilization for

both the cement mill was very less which was due to less demand in the market as they were

fairly new in the business in Bangladesh. Both the mill was also run with a lower capacity as

that was sufficient to meet the market demand. But it is sure that if autonomous maintenance

is implemented properly LSCL will enjoy a greater benefit from this.

82

6.2 Recommendation In this project I tried to analyze the existing system in the Lafarge Surma Cement Limited. I concentrated more in the maintenance side than that of the production side. From the result it is evident that the analysis did not show any increase in the production rate as that time I did not consider the factor which are responsible for the degraded output rate. Further work on this sector is recommended. In this project the human factor also not included and I did not counted the human factor which can also effect the down time as well as the production rate. This is also another sector which can be included in further study. All the calculation was made on the basis of hypothetical assumption, so it is highly recommended to impellent the recommendations which are proposed in the result section and calculate the effects from the real life. Man-machine hour was also not analyzed in the thesis work, this is also another sector on which we can focus and analyze the financial benefit from this.

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REFERENCES [1] Lafarge Surma Cement Ltd., Internal documents, 2008.

[2] Lafarge Surma Cement Limited, March4, 2010

http://eplbangladesh.com/brokerage/research/1297916433Lafarge%20Surma%20Cement%20

(March%204,%202010).pdf (Accessed 25 April, 2010)

[3] Total productive maintenance, Industrial Press Inc., 2004, 2nd Edition, by Terry Wireman

C H A P T E R 1, The History and Impact of Total Productive Maintenance,

[4] Lungberg.O (1998), Mearsument of overall equipment effectiveness as a basic for TPM

activities. International Journal of operation.and production management 18 (5):495-507.

[5] Hananto,‖ Production‘s Maintenance, A way to speed up Autonomous Maintenance,‖

Jakarta December 2004

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(Accessed 05 January, 2009)

[6] Leading manufacturing excellence: a guide to state-of-the-art manufacturing, Published

by John Wiley and Sons, 1997, Illustrated Edition, By Patricia E. Moody.

[7] Maintenance Engineering Handbook, McGraw Hill, 2008, Seventh Edition, By R. Keith

Mobley.

[8] W. Mark Fruin1 and Masao Nakamura (1997), ―Top-down Production Management: A

Recent Trend in the Japanese Productivity-enhancement Movement‖, Managerial and

decision economics, VOL. 18(7): 131–139

[9] TPM, total productive maintenance, Tokyo: Asian Productivity Organization, 1990,

English version, by Yoshikazu Takahashi.

[10] OEE-Overall Equipment Efficiency, ABB, by Francis Wauters and Jean Mathod

http://eplbangladesh.com/brokerage/research/1297916433Lafarge%20Surma%20Cement%20(March%204,%202010).pdf

http://eplbangladesh.com/brokerage/research/1297916433Lafarge%20Surma%20Cement%20(March%204,%202010).pdf

http://www.migas-indonesia.com/files/article/%5BMaintenance%5DZero_Breakdown.pdf

http://openlibrary.org/b/OL1626750M/TPM,-total-productive-maintenance

http://openlibrary.org/a/OL799185A/Yoshikazu-Takahashi

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http://library.abb.com/global/scot/scot296.nsf/veritydisplay/4581d5d1ce980419c1256bfb006

399b9/$File/3BUS094188R0001.pdf_-_en_OEE_Whitepaper_-

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[11] TPM Seminar for Management, BASF, KMAC, http://lo.lafarge.com (Accessed 11 July

April, 2009)

[12] Reliability in automotive and mechanical engineering, Springer,1985,2nd Edition, by

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[13] Electronic Reliability Design handbook, MIL-HDBK-338B, 1 October 1998

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http://lo.lafarge.com/

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APPENDIX

Effect of Autonomous Maintenance (AM) on Plant Reliability ...

Documents

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