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Journal of Engineering Research and Studies E-ISSN 0976-7916
JERS/Vol.I/ Issue II/Oct.-Dec.,2010/177-194
Research Article
USE OF SHAININ TOOLS FOR SIMPLIFYING SIX
SIGMA IMPLEMENTATION IN QMS/ISO CERTIFIED
ENVIRONMENT AN INDIAN SME CASE STUDY Anand K. Bewoor*, Maruti S. Pawar
Address for Correspondence
*1Mechanical Engineering Dept.,Vishwakarama Institute of Information Tech.,Kondhwa
(Bk), Pune 411048, Maharashtra, India 2Professor and Vice-Principal, B. M. I. T., Solapur University, Solapur Maharashtra, India.
E-mail: [email protected], [email protected]
ABSTRACT Six sigma for small- and medium-sized enterprises (SMEs) is an emerging topic among many
academics and Six Sigma practitioners over the last two to three years. Very few studies have been
reported about the successful applications of Six Sigma in SMEs. Main objective of this paper is to
examine the extent of usefulness of a simpler but not very frequently used methodology known as the
Shainin methodology for simplifying the implementing Six Sigma. To confirm whether Six Sigma
implementation is simplified, this paper highlights the comparison of three DOE approaches viz.
Classical, Taguchi and Shainin methodology.
A case study based research work done in ISO certified Indian SME, concludes that, Six Sigma
implementation process can be simplified by using Shainin tools and proper use companys ISO/QMS.
KEYWORDS Six Sigma, Shainin Tools, QMS, Indian SMEs.
1. INTRODUCTION
In recent past, academicians, practitioners
and organizational researchers have
recognized that the Quality Management
System (QMS) process and the Six-Sigma
process are disciplines that have a
powerful potential to affect an
organizations ability to compete within
an increasingly global and dynamic
marketplace (Falshaw et al., 2006). QMS
certification (such as ISO 9000, TS
16949) demonstrates the capability of an
industry to control the processes that
determine the acceptability of the product
or service being produced & sold. These,
traditional QMS are having some
limitations like methodological assistance
etc. (Bewoor and Pawar, 2008). But new
QM methods continue to grow (Xingxing
Zu et. al., 2008) for example, Six Sigma,
which is an organized and systematic
method for strategic process improvement
and new product and service development.
Six Sigma relies on statistical methods and
the scientific method to make dramatic
reductions in customer defined defect
rates (Linderman et al., 2003). Since its
initiation at Motorola in the 1980s, many
companies including GE, Honeywell,
Sony, Caterpillar, Johnson Controls etc.
have adopted Six Sigma and obtained
substantial benefits (Pande et al., 2000).
Spectacular development of an
organizational performance due to Six
Sigma implementation many companies
are reported in the published literature.
Antony and Banuelas (2002) presented the
key ingredients for the effective
introduction and implementation of Six-
Sigma in manufacturing and services
organizations as: Management commit-
ment and involvement, Understanding of
Six Sigma methodology, tools, and
techniques, Linking Six Sigma to business
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Journal of Engineering Research and Studies E-ISSN 0976-7916
JERS/Vol.I/ Issue II/Oct.-Dec.,2010/177-194
strategy, to customers, to suppliers, project
selection, reviews and tracking,
organizational infrastructure, Cultural
change, Project management skills,
Training. All these ingredients make the
Six Sigma process as a complex process
and very little efforts has been made for
simplifying the process of Six Sigma
implementation process by making use of
existing QMS and by selecting proper
implementation tools. Some of the
criticisms of the Six Sigma methodology
perhaps stems from the fact that it is
sometimes too statistical and beyond
comprehension of the people involved in
implementing it in practice. Eckes (2001)
is of the opinion that Six Sigma initiatives
can fail if the organization believes that
better quality is possible only through the
use of sophisticated statistical tools. The
objective of this paper is to examine as to
how to simplify and demystify the use of
Shainin tools for Six Sigma
implementation tools. At present, the
impacts of QMS and Six Sigma processes
on an organizations ability to compete
have been examined independently. Very
little emphasis has been given by the
researchers to conceptually examine the
potential impact of the synergistic effects
that might be gained from merging various
quality management principles and those
of Six-Sigma process. After doing clause-
wise analysis Bewoor and Pawar, (2008)
had proposed the Six Sigma+QMS/ISO
an integrated concept and successfully
validated its applicability with the help of
case study based research. This has
resulted in to more benefit on operational
level (Bewoor and Pawar, 2009). This
case based study helped us to understand
that if we use simple to use tools, we can
simplify Six Sigma implementation
process. The observations and experiences
in the above case study leads to question
about how to simplify the implementation
of Six Sigma with or without QMS/ISO
systems. The main complex part of the
implementation of Six Sigma is the
selection and use of tools for solving
problems. It is observed that, the efforts to
simplify the implementation of Six Sigma
are needed in the area of use of tools. One
of such efforts/studies is presented below.
2.PRESENT METHODOLOGIES FOR
SIX SIGMA IMPLEMENTATIONS
Pyzdek (2003) has classified Six Sigma
tools into three categories (refer table 1),
(i) Basic Six Sigma methods (are further
categorized as problem solving tools, 7M
tools, and knowledge discovery tools). (ii)
Intermediate Six Sigma methods include a
host of enumerative and analytical
statistical tools like Distributions,
Statistical inference, Basic control charts,
exponentially weighted moving average
(EWMA) charts etc.). (iii) Advanced Six
Sigma methods are Design of experiments
(DOE) Regression and correlation analysis
Process capability analysis etc. At the
heart of the Six Sigma approach is the
application of DOE techniques. These
techniques help to identify key factors and
to subsequently adjust these factors in
order to achieve sustainable performance
improvements.
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Journal of Engineering Research and Studies E-ISSN 0976-7916
JERS/Vol.I/ Issue II/Oct.-Dec.,2010/177-194
Table 1 : Basic Six Sigma Tools
Problem Solving Tools 7M Tools Knowledge Discovery
Tools
Process mapping Affinity diagrams Run charts
Flow charts Process decision program charts Descriptive statistics
Check sheets Matrix diagrams &
Tree diagrams
Histograms
Pareto analysis Interrelationship diagraphs Exploratory data analysis
Cause-and-effect
diagrams
Prioritization matrices
Scatter plots Activity network diagrams
(Source: Pyzdek, 2003)
While the basic and intermediate methods
are relatively easier to understand and use,
the advanced methods are perceived to be
difficult to comprehend and interpret.
Design of Experiments (DOE) is one such
tool. The complexity of these DOE
techniques that are often cited by
companies as to the reason why they are
unable to employ Six Sigma. A short
overview of the DOE techniques is
presented next.
2.1 Experimental Design using
Classical and Taguchi Approach
A classical DOE approach would have
meant application of factorial designs
requiring much more time and effort, and
above all, it would have required changes
in machine settings. Classical DOE
requires large data collection to conduct
the analysis. Six Sigma process
improvements consist of analyzing
relationships between an output variable
(Y) explained wholly or partly by process
variables (Xs) that affect the output. A key
step in Six Sigma projects is the
identification of the root cause of the
problem out of the potential Xs.
Experimental design is one of the tried
and tested statistical techniques long used
by industrial engineers to identify the key
variables affecting output. Through
designed experiments, changes are
deliberately introduced into the process to
better understand which of the Xs are
affecting the output variable.
There are two well-known approaches
to experimental design. The first approach
is the classical design of experiments
credited to Sir Ronald Fisher who initially
experimented in the field of agriculture.
However, this method is now widely used
in many fields. The second approach is the
Taguchi approach pioneered by Dr
Genichi Taguchi of Japan who adopted the
classical approach to reintroduce the
concept of orthogonal arrays used for
designing experiments in different fields
(Rao, et al.). The commonly used classical
Design of Experiment (DOE) tools are the
family of factorial experiments consisting
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of full factorial designs and fractional
factorial designs. A full factorial allows us
to test all possible combinations of factors
affecting output in order to identify which
ones are more dominant. A fractional
factorial tests just a fraction of the
possible combinations. Though a very
popular tool, many engineers and quality
practitioners find design of experiments
difficult primarily because of the
complexity of having to create the
conditions for conducting the experiments
in an industrial environment where
interrupting production lines and changing
machine settings may be sometimes
difficult and unproductive.
2.2 Shainin DOE Approach
An alternative to the Classical and
Taguchi experimental design is the lesser-
known but much simpler Shainin DOE
approach developed and perfected by
Dorian Shainin (Bhote and Bhote, 2000),
consultant and advisor to over 750
companies in America and Europe.
Shainins philosophy has been, Dont let
the engineers do the guessing; let the parts
do the talking. Shainin recognized the
value of empirical data in solving real-
world problems. He introduced the
concept of Red X, the dominant source of
variation, among the many sources of
variation of a problem that inevitably
accounts for nearly all the unwanted
effect.
In fact, Shainin (Shainin, 1995; 1993b)
had classified all causes of chronic quality
problems into three Xs, viz., the Red X,
the Pink X- the second most important
cause(s), and the Pale Pink X the third
most important cause(s). According to
him, these three Xs together account for
over 80 per cent of the variation that is
allowed within the specification limit and
when captured, reduced, and controlled,
these can eliminate this variation. Shainin
developed techniques (Shainin and
Shainin, 1990; 1992a; 1992b; 1993a;
1993b; Shainin, Shainin and Nelson,
1997) to track down the dominant source
through a process of elimination (Shainin,
1993b), called progressive search. These
techniques, also referred to as the Shainin
System for quality improvement,
developed over a period of over 40 years,
are simple but at the same time powerful
and easier to interpret and implement in an
industrial environment. In a way, these
may be considered as the non-parametric
equivalent of Taguchis DOE as they do
not make any restrictive assumptions
about population parameters. The Shainin
techniques are primarily known to
produce breakthrough improvements in
eliminating chronic quality problems.
These are highly effective in pinpointing
towards the root cause and validating it.
No statistical software was needed to
analyze the data. In fact, Shainin DOE
does not even require knowledge of
difficult statistical tools. Simple operation
like counts, additions, subtractions, etc.,
makes calculations relatively easy. In
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addition, the success of the projects can
lead to a very positive effect on the morale
of the employees in terms of convincing
them that Six Sigma can be implemented
without complex statistics and big jargons.
The subject of the Shainin methods is very
vast and this paper highlights the
applicability of only a few of the Shainin
tools. However, there is a lot of scope for
more research on this methodology
particularly comparative research of some
of the Shainin methods like Paired
Comparison and B Vs C Analysis vis--
vis the more popular statistical tools like
factorial designs and non-parametric
testing. Although these methods are not
necessarily the best, according to Steiner
et al. (2008), the guiding principles of the
Shainin tools are powerful, and at least, in
combination, unique. Also, these tools are
best suited for batch to high volume
production.
3. FINDINGS FROM VARIOUS
CASE STUDIES ABOUT DOE
APPROACHES
Bhote and Bhote (2000) described these
tools in their books, but there have been
many criticisms regarding their claims and
the tools described. Though, Nelson
(1991) and Moore (1993) criticized the
Shainin System as unsubstantiated and
exaggerated, Steiner, et al (2008), are of
the opinion that some of the ideas behind
the Shainin System are genuinely useful.
Goodman and Wyld (2001) offered a case
study involving the use of Shainin DOE in
an industrial operation. Applications of the
Classical and Taguchi methods in various
fields have been extensively researched. In
contrast, the Shainin system has not been
extensively reviewed, academically, and
very limited studies have been carried out
in this area.
3.1 Studies about comparison of
DOE approaches
Bhote (2000) compared Shainin
techniques with Design of Experiments
and Taguchi methods, in the context of the
electronics industry and concluded that the
Shainin techniques are simpler, less
costly, and statistically more powerful
than the other two. Logothetis (1990) also
evaluated the Shainin techniques in
relation to the Taguchi methods and
statistical process control methods.
Verma, et al (2004) used a slightly
different approach to compare the
methods. In their study, three cases of
Taguchi experiments were picked up from
the available literature and the Shainin
method was then re-applied to find out
whether it had an edge over the other DOE
techniques. A comparison between
Taguchi and Shainin techniques in an
aerospace environment was offered by
Thomas and Anthony (2005). A few other
authors who have studied these techniques
are Ledolter and Swersey (1997), De
Mast, et al. (2000) and Steiner and
MacKay (2005). The Classical DOE,
Taguchi DOE, and Shainin DOE are
compared with each other in Table 2.
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Table 2:Comparison of Classical, Taguchi, and Shainin DOE Approaches
Items for
compari-
son
Classical DOE Taguchi DOE Shainin DOE
Primary
tools
Factorial experiments
Orthogonal arrays
a. Component search,
b. Multi-vari analysis,
c. Paired comparison,
d. Product/Process Search or,
variable search, e. Full
factorials, f. B vs. C (Better
vs. Current) analysis, Scatter
plots.
Advan-
tage
Effective when
interaction effects are
not present
(20 to 200%
improvements).
Limited possibilities
for optimization.
Effective when
interaction
effects are not present
(20 to 200%
improvements).
Limited possibilities for
optimization.
Very powerful irrespective of
the presence or absence of
interactions. Maximum
optimization possible.
Cost/Tim
e Moderate Moderate Low
Training 3 to 5 days 3 to 10 days 1 to 2 days
Complexi
ty Moderate High
Low (simple & basic
mathematical operations)
Facility &
Scope
Requires use of
statistical software
e.g., SAS, SPSS, etc.
Used mainly in
production.
Requires use of
statistical software e.g.,
SAS, SPSS, etc. Used
mainly in pre-
production & can be
used at the design stage
under certain
constraints.
Software not necessary.
Ease of
Imple-
mentation
Moderate (Requires
knowledge of
statistics. Engineers
find methods
complex to
comprehend and
interpret.)
Poor
High (Almost no knowledge
of statistics required. Easy to
understand at all levels
including shop floor workers,
engineers, and suppliers, thus
creating an overall positive
impact.
(Bothe & Bothe, 2000)
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An examination of the three approaches
clearly indicates that the Shainin tools
have an edge over the other two
approaches in terms of cost, time, training,
complexity, scope, and ease of
implementation. The following work
highlights the tools and techniques that
were used by Indian SME, a
manufacturing unit of Gange Industries
(GI) in their development of the six sigma
programme
4. CASE STUDY
This case-study was successfully
completed in the welding unit of GI,
which is a SME was established in 1985,
located at Bhosari M.I.D.C., Pune,
Maharashtra State in India. GI has grown
to become a one of the major player in
processing/manufacturing of automobile
sheet-metal parts. GI is ISO 9001 and TS
16949 certified and has implemented
company wide QM, Kaizen and TPM
initiatives to good effect.
The company from their past experience
found that the QM process and its
associated systems were too slow in
identifying and responding to problems
primarily, since they were developed to
obtain long-term strategic direction and
focus. Therefore, company officials had
accepted and initiated move towards use
of Shainin tools for implementation of
Six Sigma + QMS integrated approach
for increase the process quality,
productivity intern reducing process cost.
Until the introduction of the integrated
strategy, the company attended to quality
problems in an often ad-hoc and
unstructured manner.
The following section followed how
the company followed the proposed
methodology in an attempt to provide a
structured approach to solving critical to
quality (CTQ) problems within the
company and to achieve enhanced process
quality, productivity, customer satisfaction
and internal benefits through a case study
of one particular project undertaken.
Six Sigma DMAIC Process
The six sigma process concentrates on a
simple five phase methodology called
DMAIC (Define, Measure, Analyze,
Improve, Control). The company followed
this approach and each stage is explained
in detail in the following section of the
paper.
Define Phase: The data available
(collected through QMS) related to type,
frequency and amount of rework done at
GI is analyzed. Our team (which includes
companys management representative,
managers, engineers and author) at GI
confirmed that, parts named Assy-sub
structure with floor (613 LP RUSSIA)
(XXX 6100 0182), which fits into
assembly frame of light commercial
vehicle after welding on Welding M/C
ST-CO2-17 machine was under rejection
because of defective welding (non
uniform welding, weld penetration, dry
welding, weld under cut and spatter etc.),
which resulted in to annual Cost of Poor
Quality (COPQ) about INR 2Lakh/-.
Process stages, where the problem
detected are in-process inspection and
final inspection. This project was
undertaken to achieve certain objectives
viz. productivity improvements in terms of
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reduction/elimination of reworks and
reducing process cost [tangible], customer
satisfaction, and increase in confidence on
shop floor [intangible]. Hence,
repeatability and reproducibility study was
required for validating the measurement
system. Process Mapping is carried out
(refer figure 1),
Measure and Analyze Phase: A
brainstorming exercise was carried out by
a multi-disciplinary team of engineers
within the company. The team identified
the factors that could influence the product
quality. A cause-and-effect diagram was
developed (refer figure 2) to identify the
key sources of variation during the
welding process. Two potential
Suspectable Sources of Variations (SSVs)
were finally listed as: Sheet material
thickness, Welding Process itself.
Figure 2: Cause-and-Effect Diagram
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Without taking educated guesses as to the
factors of real importance, authors have
suggested to adopt the Shainin
Techniques. The Shainins Techniques
been employed to identify whether the
primary cause of shabby/defective
welding lay within the process itself or
within the components used. This allowed
for a first stage filter to be employed that
cut down the factors to a manageable
number. Key stages, in which Shainin
tools were applied, are explained below.
Initial tool selected for measuring and
analyzing the response was Product
Process Search, as of variations in the
identified suspectable sources of
variations (SSV) i.e. input material
parameter (as compared with their
standard specification) viz. SSV-1.
Material Thickness (Specifications 2.0
mm +/- 0.18), gets changed during
processing. Data was collected for 100
samples.
Observation 1 It has been observed that,
minimum and maximum value of sheet
metal (raw material) thickness as an
important input to production process
belongs to same category of response.
Therefore, as per Product Process Search
method the end-count is zero. Hence, it
has been concluded that, SSV-1: Input
material parameter (i.e. Thickness) is not
creating problem. Next another
brainstorming session has concluded for
characterization of CO2-Welding process
as process itself is yielding in to
variations, which is required to be
analysed. Hence, relation can be written
as; BigY (Response i.e. Defective welding)
= f [X (Sources of variations i.e. CO2
Welding process)]. Therefore, new SSVs
are now related to CO2-Welding process
are listed viz. Voltage, Current, Gas Flow
and Wire Feed Rate. To check whether
any relationship exists within the
identified parameters or not; data related
to all these parameters are collected (refer
table 3), regression analysis is carried out
and Graphs are plotted. Graph of Wire
Feed Rate vs Current clearly shows the
positive relationship (refer figure no. 3).
Hence, new SSVs identified parameters
related to CO2-Welding process are now
limited to: Voltage, Wire Feed Rate and
Gas Flow.
As the identified parameters were design
parameters of process and number of
parameters are equal to 3 hence, it has
been decided that, process characterization
analysis i.e. Full Factorial Analysis tool is
to be used. All stages of full factorial
method are explained as follows,
Stage 0: As the response is attribute in
nature, consider current setting as the
setting and identify + setting on the basis
of experience on domain expert for each
parameters (refer table 4).
Stage 1: To find out whether the
parameters and the levels identified in
stage 0 are correct or not. Then, we have
to produced 3 batches in setting and 3
batches in + setting. Calculate D/d ratio,
if D/d ratio is >=1.25 and
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tabulated in table 5. D/d ratio is 0.4, which
indicates that, the levels identified in stage
0 are not correct. Hence, new parameters
levels are identified by considering earlier
+ ve setting as new - setting and new
+ ve settings for all parameters are
identified and set (refer table 6). Again
new trials are conducted and the results
are tabulated in table 7. D/d ratio is 10,
which indicates that the levels identified in
2nd settings are acceptable for further
consideration.
Stage 2: Construct factorial table and
collect the data for each combination in
the factorial table and quantify the
contributions of the interactions.
Table 8 shows factorial design and plan
of experimentation. Accordingly
experiments were performed, which
resulted in to following important
conclusions.
Parameter- A: As if we change from +
level to - level then response increases by
2.5 points.
Parameter- B: As if we change from +
level to - level then response decreases by
1.5 points.
Parameter- C: As if we change from +
level to - level then response decreases by
5 points.
Stage 3: Make a simple mathematical
equation based on the contribution of
significant parameters and arrive at the
optimal setting.
Y= 84.875 3.125 A + 14.162B + 4.875C
+2.625 AB 4.375 BC 7.125 CA +
7.625ABC
As response Y considered is
shabby/defective welding hence, our
objective is lower the better. Using above
equation, offline iterations are done.
While doing iterations +ve settings are
refereed as 1, - settings are referred as
-1. Values some of the offline iterations
and its calculated responses are tabulated
in table 9. Then, experiments are carried
out using the levels of the parameters for
which responses are zero or less than zero
and physical outputs are analyzed.
Response for setting in case of experiment
no. 9 (shown in same table) resulted in to
proper welding (considered as an optimum
output).
Improvement Phase: Conclusions of
earlier phase (identified optimum levels of
the parameters as shown in table 10) are
used as an input to this phase. Once
optimum settings are set then, it is
necessary to validate it. This was done, by
using the Shainin B vs. C analysis, which
is a confirmation tool to verify whether
the actions taken have actually improved
the process (Bhote and Bhote, 2000). In
this case, 6B vs. 6C, i.e., 6 batches (10
units per batch) with modification and 6
(10 units per batch) without modification
(B with modification and C without
modification) was analyzed to validate the
improvement action, i.e., the modification
of CO2 machine operating parameters
(table 11).
The data in table 12 exhibited the
responses with B and C conditions. As per
rule of this technique, the final analysis is
done based on the end-count scheme. In
this case, end count is 8 (greater than 6),
which confirms that identified root causes
are correct.
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Further, the result clearly validates the
improvement against the criteria
mentioned in table 13. The data has
exhibited no overlaps of the responses
with B condition and C condition. The
conclusion being that the process has been
improved by changing the CO2 welding
machine operational specifications as
mentioned in table 10. New specifications
not only helped to improve the quality
level but also productivity by reducing
defect/rework rate and optimizing the use
of resource and time (e.g. Wire Feed Rate
from 10 Min/min to 6.5 Min/min and Gas
Flow from15 Lit/min to 14 Lit/min).
Table 3: Data related to all these interactions among identified parameters
Sr. No. wire feed voltage current
1 50 27 40
2 55 13 90
3 55 16 100
4 55 18 80
5 55 20 100
6 55 22 110
7 55 22 110
7 55 25 100
9 55 28 90
10 55 30 90
11 65 17 100
12 65 19 100
13 65 23 100
14 75 30 160
15 80 20 150
16 80 27 140
17 100 26 190
Table 4: First Setting of levels of each parameter
Sr. No. Parameter UOM Existing Setting (- ve ) Modified Setting (+ ve )
A Wire Feed Rate Min/min 10 7
B Voltage V 26 20
C Gas Flow Lit/min 15 8
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Table 5: First Trial
Trial - Setting + Setting
1st Trial 10 50
2nd Trial 50 50
3rd Trial 40 60
Median 40 50
Range 40 10
D = Difference Between Two Medians 10
d = Average of Two Ranges 25
D/d 0.4
Table 6: Second Setting of levels of each parameter
S. N. Parameter UOM Existing Setting ( - ve ) Modified Setting (+ ve )
A Wire Feed Rate Min/min 7 4
B Voltage V 20 18
C Gas Flow Lit/min 8 6
Table 7: Second Trial
Trial - Setting + Setting
1st Trial 50 100
2nd Trial 50 100
3rd Trial 60 100
Median 50 100
Range 10 0
D = Difference Between Two Medians 50
d = Average of Two Ranges 5
D/d 10
Table 8:Factorial Table
Factors (Main Effects) Factor interaction
A B C AB BC CA ABC Response Median
7 " - " 20 " - " 8 " - " " + " " + " " + " " - " 50 , 50, 60 52
4 " + " 20 " - " 8 " - " " - " " + " " - " " + " 70 70
7 " - " 18 " + " 8 " - " " - " " - " " + " " + " 100 100
4 " + " 18 " + " 8 " - " " + " " - " " - " " - " 70 98
7 " - " 20 " - " 6 " + " " + " " - " " - " " + " 100 100
4 " + " 20 " - " 6 " + " " - " " - " " + " " - " 60 59
7 " - " 18 " + " 6 " + " " - " " + " " - " " - " 100 100
Parameters
Settings
4 " + " 18 " + " 6 " + " " + " " + " " + " " + " 100, 100,
100 100
" - " 88 70.25 80 82.25 89.25 92 77.25
" + " 81.75 99.5 89.75 87.5 80.5 77.75 92.5
Sign " - " " + " " + " " + " "-" " - " " + "
Difference 6.25 29.25 9.75 5.25 8.75 14.25 15.25
Coeff. 3.125 14.625 4.875 2.625 4.375 7.125 7.625 84.874
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Table 9:Offline iterations, its calculated and actual responses
Expt.
No. Wire Feed Voltage Gas Flow Constant Response Remark
1 0 0 0 84.875 84.88
2 -1 -1 -1 84.875 52
3 1 1 1 84.875 100
4 -.5 -2 -2 84.875 10.19 Poor adhesion
5 -0.45 -2 -2.5 84.875 0.0
6 -0.5 -3 -3 84.875 -52.50 Poor adhesion
7 -0.6 -5 -5 84.875 -248
8 -0.6 -9 -7 84.875 -507.20 Poor adhesion
9 -0.65 -9 -7 84.875 -684 OK 10 -2 -11 -7 84.875 -1652 High Penetration
Table 10: Existing and Optimum Settings
Sr.
No.
Parameter UOM Existing Setting
( -) ve
Optimum Setting
(0 - Target )
A Voltage V 26 28
B Current A 200 150
C Wire Feed Rate Min/min 10 6.5 D Gas Flow Lit/min 15 14
Table 11: B vs. C analysis
1 Part number selected for validation ASSY substructure with floor
Better Condition Optimum Settings (Refer table 10 ) 2 Current Condition -
3 Sample size 6B,6C
4 Sample type Batches
5 Response decided for monitoring % Rejection
6 Lot quantity (for batches) 10
Table 12:B vs. C Response
Lot no. Better ( B ) Current ( C )
1 0 40
2 0 30
3 10 10
4 10 40
5 0 30
6 0 40
Table 13: Criteria for validating improvements and results
Sr. no. Criteria for validating improvements Results
1 Part selected for validation Sub structure assembly with floor
Average of B 3.33 2
Average of C 31.66
3 Xb Xc (Amount of Improvement) 28.33
4 Sigma (B) 4.71
5
Is [Xb - Xc] greater than [K x Sigma (b)]
(Where K is std value = K = 2.96 @ 95%
Confidence Level )
Yes [(28.33 > 19.78]
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The improvements identified were also
used to set the action plan for other
varieties of such components for
horizontal deployment.
Control Phase:
The focus of the control phase is to sustain
the gains of the improvement phase. This
is usually achieved by documentation and
standardization of the control measures.
For controlling the process at Six Sigma
level, following actions were suggested.
Appropriate modifications have been
done in CO2 welding machine operating
and training manuals.
Procedure has been developed for
periodic monitoring of CO2 welding
machine operational specifications w. r. to
quality level of output.
Implemented controls to make sure
that the actions taken in Phase-III are done
forever.
All these modifications have been
included as a part of Company-QMS
procedure to ensure the reliability of Six
Sigma level quality of the process.
The operational framework developed and
used in this research-work is described in
figure 4.
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It clearly shows the major stages in the
process integration and implementation. It
shows initially the sequential nature of the
stages whereby the Six Sigma phases are
using appropriate imputes from company
QMS database to continently execute the
project. The operational framework also
shows the stages in sequence whereby the
six sigma DMAIC phases are using
accurately Shainin quality tools.
5. DISCUSSION AND CONCLUSIONS
The aim of this project is to defeat the
biggest excuses cited by SMEs as the
reasons Six Sigma is not feasible, incurs
high costs and involve complexity of
implementation. In addition, it helps to
break down so many of the barriers that
stand in the way of individuals using
statistical and/or unfamiliar problem
solving methods by acting as a step-by-
step guide. This research work focus on
use of Shainin tools specifically, as they
are easy to understand, involves simple
mathematical calculations (so that bottom-
line people can also understand it very
easily) and time required for training is
also less, which is one of the important
requirements of SMEs. During this case
study, during use of Shainin tools, small
samples of BOB and WOW pieces were
sufficient to analyse the data as reported
earlier. A very important factor is that data
collection was done for the project
undertaken online without disturbing the
regular production.
Thus in short, we can understand that, use
of Shainin tools for simplifying Six
Sigma implementation can provides an
appropriate methodology for SMEs for
delivering certain objectives set by ISO
such as: prevention of defects at all stages
from design through servicing; techniques
required for establishing, controlling and
verifying process capability and product
characterization; investigation of the cause
of defects relating to product, process and
quality system; continuous improvement
of the quality of products/services.
From the results of case study based
research work we draw following
conclusions,
i. The key phase of the DMAIC
methodology is the measure and
analysis phase. The tools and
techniques used in this phase
determine the success or failure of
the project to a large extent. In
both the projects, the Shainin tools
have been very effectively used to
pinpoint the root causes and
validate the improvement actions.
ii. No statistical software was needed
to be used to analyse the data. In
fact, Shainin DOE does not even
require knowledge of difficult
statistical tools. Simple operation
like counts, additions, subtractions
etc., makes calculations relatively
easy. Therefore the training
required for application of Shainin
tools is simple and requires less
time (1-2 days).
iii. In addition, the success of the
projects had a very positive effect
on the morale of the employees in
terms of convincing them that Six
Sigma works without complex
statistics and big jargons.
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iv. Existing company QMS
procedures has assisted
/complimented in all stages of
implementation of Six Sigma.
v. Operational framework developed
and used in this research-work has
validated for its implementation
and found to be a useful concept
for improving quality and
productivity/performance of SME.
vi. The project was completed within
a span of almost three months. For
the company, the estimated
savings from this project was
more than INR 2 lakhs per annum.
The guiding principles of the Shainin tools
are powerful, and at least, in combination,
unique. Therefore, we conclude that,
applying simplified Shainin tools based
Six Sigma methodology to the existing
company QMS process is the best way for
SMEs to achieve the optimal results in
quality progress towards TQM in
customer satisfaction.
This paper highlights the applicability of
only a few of the Shainin tools. There is a
lot of scope for more research on this
methodology as its most of the
terminology is trademarked and legally
protected, limiting academic debate and
discussion on this system of problem
solving, which despite many criticisms
and having been largely overshadowed by
the classical and Taguchi techniques in the
past, is now gradually being given its due
recognition.
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