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SIX SIGMA Page | 1 Department of Mechanical Engineering AJCE A STUDY OF SIX SIGMA METHODOLOGY SEMINAR REPORT DEPARTMENT OF MECHANICAL ENGINEERING AMAL JYOTHI COLLEGE OF ENGINEERING KOOVAPALLY, KANJIRAPALLY, KERALA SEPTEMBER 2011

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Page 1: new FINAL REPORT -A STUDY OF SIX SIGMA METHODOLOGY

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DepartmentofMechanicalEngineering AJCE

A STUDY OF SIX SIGMA METHODOLOGY

SEMINAR REPORT

DEPARTMENT OF MECHANICAL ENGINEERING

AMAL JYOTHI COLLEGE OF ENGINEERING

KOOVAPALLY, KANJIRAPALLY, KERALA

SEPTEMBER 2011

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DepartmentofMechanicalEngineering AJCE

A STUDY OF SIX SIGMA METHODOLOGY

SEMINAR REPORT

Submitted by

ALAN KURIEN PUNNOOSE

REGISTER NO: 66893

DEPARTMENT OF MECHANICAL ENGINEERING

AMAL JYOTHI COLLEGE OF ENGINEERING

KOOVAPALLY, KANJIRAPALLY, KERALA

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AMAL JYOTHI COLLEGE OF ENGINEERING KANJIRAPALLY

BONAFIDECERTIFICATE

This is to certify that the report entitled “A STUDY OF SIX SIGMA METHODOLOGY” submitted by “ALAN KURIEN PUNNOOSE”, (Reg.No:66893), in partial fulfilment of the requirements for the award of the degree of Bachelor of Technology in MECHANICAL ENGINEERING from Mahatma Gandhi University, Kottayam, Kerala is an authentic report of the seminar presented by him.

Seminar Guide Seminar Coordinator Mrs.Tina Raju Prof. Binu Skariah Dept of Automobile Engg. Dept of Mechanical Engg.

Head of the Department Prof. Jippu Jacob

Dept. of Mechanical Engg.

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ACKNOWLEDGMENT

Apart from the efforts on my part, the success of any seminar depends largely on the

encouragement and guidance of many others. I wish to express my sincere thanks to Rev. Fr. Jose Kannampuzha, Principal of the college, for providing me with all the necessary facilities

and support.

I take immense pleasure in thanking Prof. Jippu Jacob, Head of Mechanical Engineering for

having permitted me to carry out this seminar. I take this opportunity to express my gratitude to

the people who have been instrumental in the successful completion of this seminar.

I wish to express my deep sense of gratitude to my Seminar Guide Mrs.Tina Raju, Department Of Mechanical Engineering for her able guidance and useful suggestions, which helped me in

completing the seminar work, in time.

Needless to mention that my Seminar Coordinator Prof. Binu Skariah, Department of Mechanical Engineering had been a source of inspiration and for his timely guidance in the

conduct of the seminar.

I can’t say thank you enough for their tremendous support and help. I feel motivated and

encouraged every time I attended their meetings. Without their encouragement and guidance this

seminar would not have materialized.

The guidance and support received from all the members who contributed and who are

contributing to this seminar, was vital for its success. Finally, yet importantly, I would like to

express my heartfelt thanks to my beloved parents for their blessings, my friends/classmates for

their help and wishes for the successful completion of this seminar.

ALAN KURIEN PUNNOOSE S7, Mechanical Engineering

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DepartmentofMechanicalEngineering AJCE

ABSTRACT

Six sigma is a highly disciplined approach used to reduce the process variations to the

extent that the level of defects are drastically reduced to less than 3.4 per million process, product

or service opportunities. The approach relies heavily on advanced statistical tools. While these

tools have been known earlier, these were primarily limited to the statisticians and quality

professionals. Sigma is a Greek letter to describe variability. In statistical quality control, this

means "standard deviation".

A short time ago, manufacturing was the only industry that used Six Sigma methodology but

now Six Sigma methodology has taken over the global business market. 80% of all businesses

employ, some form of six sigma methodology. Even Govt. has embraced Six Sigma culture. The

job market is wide open for Six Sigma trained or certified individual. Those who are trained can

raise quickly within their organization or help deploy the Six Sigma c ulture to other part of the

business.

Six Sigma is powerful approach achieve breakthrough improvements in manufacturing,

engineering and business processes. It is the new way of doing business that would eliminate the

existing defects efficiently and would prevent defects from occurring.

..........

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CONTENTS

S.No. Page No.

1. Introduction .......................... 1-2

2. Background Work .......................... 2-4

3. Objectives .......................... 5

4. Scope of Six Sigma .......................... 5-6

5. Methodology .......................... 7

6. Literature Survey ......................... 8-14

7. Criticism on Six Sigma .......................... 14

8. Case Study .......................... 15-20

9. Conclusion .......................... 21

10. References .......................... 22

LIST OF FIGURES Figure ..................... 6.1.1 Figure ..................... 6.2.1 Figure ..................... 6.2.2 Figure ..................... 8.1.1 Figure ..................... 8.3.1 Figure ..................... 8.3.2

xxxxx

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1.Introduction

Six Sigma is becoming a proven approach for businesses and organizations to improve their performance. The spectrum of companies actively engaging in Six Sigma today is wide from industrials like Celanese, Caterpillar, GE, Honeywell, and 3M to service/retail organizations like Starwood Hotels, Sears, and Home Depot. Six Sigma has even started in the financial industry with Bank of America and JPMorgan Chase initiating major deployments in the past two years. Probably the most exciting area is in the public and healthcare sectors with success stories emerging from city government and John Hopkins Medical.

So what is all this excitement about? Haven’t these quality tools been around for years? Is it just the fact that people have strange names like Champion, Green Belt, Black Belt and for the chosen few, Master Black Belt? Okay, if it is not the names then what? Six Sigma’s success revolves around the fundamental elements needed for any successful organization. Six Sigma starts with a vision of delivering products and services to customers with no defects from the eyes of the customers. For companies it is vital to deliver these products and services at a profit. Once the organization has created their own vision of Six Sigma, the business leaders need to define their organization’s objectives in numerical terms. These “high-level metrics,” often called big Y’s in Six Sigma, are the foundation for identifying project y’s that

A STUDY ABOUT

SIX SIGMA METHODOLOY

September 24 2011

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Six Sigma Belts will execute projects on. With big Y’s in hand, business leaders called Six Sigma “Champions” breakdown these organizational level Y’s into smaller y’s a project leader called a Green Belt or Black Belt can work from.

So what’s next, do business leaders take a hands-off management by objectives (MBO) approach of, “I don’t care how you do it as long as you get results!”? For Six Sigma organizations the answer is a loud “NO.” Champions do care how projects are executed and have appointed highly trained Master Black Belts to assist and mentor project leaders in applying the Six Sigma method to manage their projects. I believe this is the key to Six Sigma’s success. In a past life I participated in a high-level meeting with executives from the world leader in the production of a product we all know. The purpose of the meeting and visit was to evaluate a critical new product design. All of the high-tech executives were dressed in dark Italian business suits complemented with gold and diamonds. I listened closely to each question these executives asked. I never once heard “how much?”, “when?” or even “why?” – every question was “by what method?.” Methodology is what Six Sigma is about.

2. Background Work

The six sigma approach was first introduced and developed at Motorola in early 1990s. Later in the mid-nineties, General Electric and Allied Signal adopted it. According to Jack Welch CEO of GE "Six sigma is the most challenging and potentially rewarding strategy GE have ever undertaken" GE listed tremendous benefits of the approach in their annual report in 1997.

Since the 1920’s mathematicians and engineers have used the word ‘sigma’ as a symbol for a unit of measurement in product quality variation. (Note it's sigma with a small 's' because in this context sigma is a generic unit of measurement.)

In the mid-1980's engineers in Motorola Inc in the USA used 'Six Sigma' an informal name for an in-house initiative for reducing defects in production processes, because it represented a suitably high level of quality. (Note here it's Sigma with a big 'S' because in this context Six Sigma is a 'branded' name for Motorola's initiative.)

(Certain engineers - there are varying opinions as to whether the very first was Bill Smith or Mikal Harry - felt that measuring defects in terms of

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thousands was an insufficiently rigorous standard. Hence they increased the measurement scale to parts per million, described as 'defects per million', which prompted the use the the 'six sigma' terminology and adoption of the capitalized 'Six Sigma' branded name, given that six sigma was deemed to equate to 3.4 parts - or defects - per million.)

In the late-1980's following the success of the above initiative, Motorola extended the Six Sigma methods to its critical business processes, and significantly Six Sigma became a formalized in-house 'branded' name for a performance improvement methodology, ie., beyond purely 'defect reduction', in Motorola Inc.

In 1991 Motorola certified its first 'Black Belt' Six Sigma experts, which indicates the beginnings of the formalization of the accredited training of Six Sigma methods.

In 1991 also, Allied Signal, (a large avionics company which merged with Honeywell in 1999), adopted the Six Sigma methods, and claimed significant improvements and cost savings within six months. It seems that Allied Signal's new CEO Lawrence Bossidy learned of Motorola's work with Six Sigma and so approached Motorola's CEO Bob Galvin to learn how it could be used in Allied Signal.

In 1995, General Electric's CEO Jack Welch (Welch knew Bossidy since Bossidy once worked for Welch at GE, and Welch was impressed by Bossidy's achievements using Six Sigma) decided to implement Six Sigma in GE, and by 1998 GE claimed that Six Sigma had generated over three-quarters of a billion dollars of cost savings. (Source: George Eckes' book, The Six Sigma Revolution.)

By the mid-1990's Six Sigma had developed into a transferable 'branded' corporate management initiative and methodology, notably in General Electric and other large manufacturing corporations, but also in organizations outside the manufacturing sector.

By the year 2000, Six Sigma was effectively established as an industry in its own right, involving the training, consultancy and implementation of Six Sigma methodology in all sorts of organizations around the world.

That is to say, in a little over ten years, Six Sigma quick became not only a hugely popular methodology used by many corporations for quality and process improvement, Six Sigma also became the subject of many and various training and consultancy products and services around which developed very many Six Sigma support organizations.

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Six Sigma and Design of Experiments

Once an organization has decided on the method and the project y’s, Belts are marched off to training “waves” bringing management-approved projects to class. DMAIC Green Belt training is normally two one-week sessions separated by one month. Black Belt training waves are extended by two additional months with two more weeks of training. The emphasis during the extended two weeks of Black Belt training is often on learning more details about advanced tools such as Design of Experiments (DOE).

So where does Design of Experiments fit into Six Sigma? Six Sigma is about understanding and controlling the variation of key process variables known as inputs or x’s in order to obtain improved results on project outputs or y’s. In Design of Experiment terms these inputs or x’s are often referred to as factors and the outputs are referred to as responses. In nearly all Six Sigma projects the relationship of the project y’s takes on the form of y=f(x1,x2,...xn). Wait a minute, isn’t this what Design of Experiments is all about? Of course, for almost 100 years Design of Experiments has been proven to be one of the best known methods for validating and discovering relationships between responses and factors. In Six Sigma terms it is discovering the relationship between outputs called y’s and inputs called x’s. Today’s Six Sigma Belts are primarily taught to focus their use of Design of Experiments in the Improve phase of DMAIC and the Optimize phase of IDOV. For DMAIC Six Sigma training the most common experimental designs taught are factorial and fractional factorial designs. Some curriculums introduce response surface designs and optimization designs at a high level. DFSS includes the experimental designs taught in all levels of DMAIC training and often expands to include the concept of robust designs. As an alternative to the classical approach, there are also a number of consulting companies teaching Taguchi designs as the preferred method for robust design.

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3. Objectives:

We can distinguish three principal objectives of the Six Sigma: higher profits, rising value and limited variations. The science of Six Sigma focuses on two mail processes. Each of them consists of three parts:

One of them is characterization of the process. In this sphere we can distinguish:

1. Diagnosis of the project (define the main idea and measure it), 2. Evaluation of the present Sigma (ability studies), 3. Analysis of the data processes.

The second process is improvement and simulation. In this area we may notice:

1. Development and optimization of the process, 2. Estimation of the new Sigma (ability studies), 3. Audit and maintenance of the process.

4. Scope of SIX SIGMA:

Following completion of Six Sigma training, it might be beneficial to look at the larger workplace issues and branch out from there. A short time ago, manufacturing was the only industry that used Six Sigma methodology. Larger and more diversified corporations actually limited Six Sigma practices to the manufacturing and production divisions. But Six Sigma methodology has taken over the global business market where nearly 80% of all businesses employ some form of Six Sigma methodology. Even the government has embraced Six Sigma culture.

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Today, listing Six Sigma expertise and certification is viewed as a career boosting move. Those who are trained can rise quickly within their organization, or help deploy the Six Sigma culture to other parts of the business. Should you decide to change careers or industries, your skills and abilities are easily transferable to the new business. The job market is wide open for the Six Sigma trained or certified individual. Companies are in the market for an individual who can come in and jump start a stalled Six Sigma program, reinvigorating the Six Sigma methodology and culture. Doing this will enable workers to go back to streamlining the core processes and improving results, products and services. No matter what level your Six Sigma training, be it Green Belt, Black Belt, or Master Black Belt, your training will transfer positively, saving the company money and resulting in higher bonuses and salaries. Diversifying your work experience draws you closer to Six Sigma methodology and certification which is a process that is totally customizable to you, depending on the training provider you choose, your industry, and the core process being analyzed and smoothed over at your place of business. An individual versed in leading the deployment of Six Sigma projects can literally pick and choose which projects to implement. The best overall Six Sigma training to enroll in is the Six Sigma Black Belt, as this is the production floor leadership role. If you are no keen on leading others, and work better as part of a team, a Six Sigma Green Belt Certification is a better option. The goal is to work toward Six Sigma certification while still in your present position. However, regardless of the title you carry, using Six Sigma methodology will benefit both you and your corporation.

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5. Methodology:

Six Sigma Digest: Black Belt Training

Define • Goal: Problem Statement, Objective, Business Case, Proj. Scope, Team • Main Tools: Project Charter, Pareto, Process Maps

Measure • Goal: Brainstorm/Prioritize Possible x’s, Validate measurement, Capability • Tools: Basic Stat, C&E, XY Matrix, Capability, MSA, P-Map, Control Chart

Analyze • Goal: Identify critical x’s • Tools: Hypothesis Tests (Normal/Non Normal) Regression & Correlation

Improve • Goal: Design, Test & Implement Improvement • Tools: DOE, Implementation/Change/Communication Plan.

Control • Goal: Lock in the Improvement • Tools: Control Plan, Poka-Yoke, SPC, SOP’s, Training Plans etc..

Six Sigma Methodology: DMAIC Roadmap

Six Sigma Digest Copyright 2010 Nixor LLC

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6.Literature Survey

6.1 What is six sigma?

Six sigma is a highly disciplined approach used to reduce the process variations to the extent that the level of defects are drastically reduced to less than 3.4 per million process, product or service opportunities (DPMO). The approach relies heavily on advanced statistical tools. While these tools have been known earlier, these were primarily limited to the statisticians and quality professionals. Sigma is a Greek letter to describe variability. In statistical quality control, this means "standard deviation". Most of us may be familiar with the normal distribution and its properties. We are aware of the properties of normal distribution :

99.73% of the area lies within mean m ± 3

95.46% of the area lies within mean m ± 2

68.26% of the area lies within mean m ±

When we proudly mention that our process capability Cp is 1.33, our process spread is ± 4 and estimated defect rate of 0.0063% or 63 defective parts per million (PPM). Moreover, when we deploy processes in production, the mean of the process can shift to the extent of approximately 1.5 defect rate will increase to a much higher value. This would be about 6200 PPM! If the process capability is improved to a Cp of 2.0 the PPM level will come down to 0.002. With a shift of 1.5 and the number of parts defective will be about 3.4 PPM. A Cp of 2.0 corresponds to the process spread of ± 6 This is shown in the figures below.

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Fig 6.1.1

Let us consider an example of an assembly with 30 parts and 5 steps. This means that there are 30x5 or 150 opportunities for a defect to occur. If we find that there are 100 defects in every 100 assemblies. This means one defect per assembly or 1 million defects in one million assemblies. This can be converted to 1000000 x (1/150) or 6666 defects per million opportunities (DPMO). This approximately corresponds to a sigma level of 3.97. The sigma quality level can be approximately determined using the equation (Schmidt and Launsby 1997) :

Refer to the following table for relation between sigma quality level and PPM. The PPM values are calculated considering a shift of 1.5

Quality & Productivity Journal : September 2000 Issue http://www.symphonytech.com

variability. In statistical quality control, this means "standard deviation". Most of us may be familiar with the normal distribution and its properties. We are aware of the properties of normal distribution :

• 99.73% of the area lies within mean m ± 3 • 95.46% of the area lies within mean m ± 2 • 68.26% of the area lies within mean m ±

When we proudly mention that our process capability Cp is 1.33, our process spread is ± 4and estimated defect rate of 0.0063% or 63 defective parts per million (PPM). Moreover, when we deploy processes in production, the mean of the process can shift to the extent of approximately 1.5defect rate will increase to a much higher value. This would be about 6200 PPM! If the process capability is improved to a Cp of 2.0 the PPM level will come down to 0.002. With a shift of 1.5and the number of parts defective will be about 3.4 PPM. A Cp of 2.0 corresponds to the process spread of ± 6 This is shown in the figures below.

Let us consider an example of an assembly with 30 parts and 5 steps. This means that there are 30x5 or 150 opportunities for a defect to occur. If we find that there are 100 defects in every 100 assemblies. This means one defect per assembly or 1 million defects in one million assemblies. This can be converted to 1000000 x (1/150) or 6666 defects per million opportunities (DPMO). This approximately corresponds to a sigma level of 3.97. The sigma quality level can be approximately determined using the equation (Schmidt and Launsby 1997) :

Refer to the following table for relation between sigma quality level and PPM. The PPM values are calculated considering a shift of 1.5

PPM

2 308,537

3 66,807

4 6,201

5 233

6 3.4

Quality & Productivity Journal : September 2000 Issue http://www.symphonytech.com

variability. In statistical quality control, this means "standard deviation". Most of us may be familiar with the normal distribution and its properties. We are aware of the properties of normal distribution :

• 99.73% of the area lies within mean m ± 3 • 95.46% of the area lies within mean m ± 2 • 68.26% of the area lies within mean m ±

When we proudly mention that our process capability Cp is 1.33, our process spread is ± 4and estimated defect rate of 0.0063% or 63 defective parts per million (PPM). Moreover, when we deploy processes in production, the mean of the process can shift to the extent of approximately 1.5defect rate will increase to a much higher value. This would be about 6200 PPM! If the process capability is improved to a Cp of 2.0 the PPM level will come down to 0.002. With a shift of 1.5and the number of parts defective will be about 3.4 PPM. A Cp of 2.0 corresponds to the process spread of ± 6 This is shown in the figures below.

Let us consider an example of an assembly with 30 parts and 5 steps. This means that there are 30x5 or 150 opportunities for a defect to occur. If we find that there are 100 defects in every 100 assemblies. This means one defect per assembly or 1 million defects in one million assemblies. This can be converted to 1000000 x (1/150) or 6666 defects per million opportunities (DPMO). This approximately corresponds to a sigma level of 3.97. The sigma quality level can be approximately determined using the equation (Schmidt and Launsby 1997) :

Refer to the following table for relation between sigma quality level and PPM. The PPM values are calculated considering a shift of 1.5

PPM

2 308,537

3 66,807

4 6,201

5 233

6 3.4

Quality & Productivity Journal : September 2000 Issue http://www.symphonytech.com

variability. In statistical quality control, this means "standard deviation". Most of us may be familiar with the normal distribution and its properties. We are aware of the properties of normal distribution :

• 99.73% of the area lies within mean m ± 3 • 95.46% of the area lies within mean m ± 2 • 68.26% of the area lies within mean m ±

When we proudly mention that our process capability Cp is 1.33, our process spread is ± 4and estimated defect rate of 0.0063% or 63 defective parts per million (PPM). Moreover, when we deploy processes in production, the mean of the process can shift to the extent of approximately 1.5defect rate will increase to a much higher value. This would be about 6200 PPM! If the process capability is improved to a Cp of 2.0 the PPM level will come down to 0.002. With a shift of 1.5and the number of parts defective will be about 3.4 PPM. A Cp of 2.0 corresponds to the process spread of ± 6 This is shown in the figures below.

Let us consider an example of an assembly with 30 parts and 5 steps. This means that there are 30x5 or 150 opportunities for a defect to occur. If we find that there are 100 defects in every 100 assemblies. This means one defect per assembly or 1 million defects in one million assemblies. This can be converted to 1000000 x (1/150) or 6666 defects per million opportunities (DPMO). This approximately corresponds to a sigma level of 3.97. The sigma quality level can be approximately determined using the equation (Schmidt and Launsby 1997) :

Refer to the following table for relation between sigma quality level and PPM. The PPM values are calculated considering a shift of 1.5

PPM

2 308,537

3 66,807

4 6,201

5 233

6 3.4

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Another concept that is used as a metric in six sigma is Rolled Throughput Yield (RTY). Let us assume that a part goes through ten operations. At each stage 99% parts are good and 1% are reject. It is not very difficult to calculate that we get good 90.43 % parts at the end of the tenth stage. This means if we start with a batch of 1000 parts, we get 904 good parts and scrap or rework 96 part! The RTY of the process is 90.43%.

While we are talking about the statistical basis of the PPM levels, six sigma is not only about statistical methods. The backbone of a successful six sigma approach is strong commitment of top management. This is like any other successful programs. Moreover, all improvements planned through six sigma projects must have a direct benefit that can be measured in terms of improvement in the bottom-line.

6.2 Six Sigma Methods

Six Sigma revolves around a few key concepts.

• Critical to Quality: Attributes most important to the customer • Defect: Failing to deliver what the customer wants • Process Capability: What your process can deliver • Variation: What the customer sees and feels • Stable Operations: Ensuring consistent, predictable processes to

Improve what the customer sees and feels • Design for Six Sigma: Designing to meet customer needs and process

capability..."

There have evolved two key methods for carrying out Six Sigma projects. The first method is the most well-defined and works best if you have a problem with an unknown solution in existing products, processes or services. This method is called DMAIC or Define, Measure, Analyze, Improve and Control. The newest method, which is in the developing stages, is called Design for Six Sigma or DFSS. The goal of DFSS is to develop a new product,process or service that is defect-free in the eyes of the customer. A number of consulting companies have invented roadmaps for DFSS like IDOV (Identify, Design, Optimize and Validate) and DMADV (Design, Measure, Analyze, Design and

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Verify).

The projects having large impact of customer satisfaction and significant impact on bottom-line are selected. Top management of the organization has very important role during selection of projects and leaders. The projects are clearly defined in terms of expected key deliverables. These are typically in terms of DPMO levels or sigma quality levels, RTY, Quality Cost etc. In the overall approach, the actual problem is converted in to a statistical problem. This is done by mapping the process, defining key process input variables (KPIVs or ‘x’s) and key process output variables (KPOVs or ‘y ’s). The power of statistical tools is used to determine a statistical solution. This is then converted in to a practical solution.

Fig 6.2.1

Six sigma projects go through four phases:

The number of ‘x’ s go on getting eliminated using various statistical and other tools. This is as if the variation is getting reduced as it passes through a funnel of the six sigma methodology. This is sometimes called the breakthrough strategy.

Quality & Productivity Journal : September 2000 Issue http://www.symphonytech.com

Another concept that is used as a metric in six sigma is Rolled Throughput Yield (RTY). Let us assume that a part goes through ten operations. At each stage 99% parts are good and 1% are reject. It is not very difficult to calculate that we get good 90.43 % parts at the end of the tenth stage. This means if we start with a batch of 1000 parts, we get 904 good parts and scrap or rework 96 part! The RTY of the process is 90.43%.

While we are talking about the statistical basis of the PPM levels, six sigma is not only about statistical methods. The backbone of a successful six sigma approach is strong commitment of top management. This is like any other successful programs. Moreover, all improvements planned through six sigma projects must have a direct benefit that can be measured in terms of improvement in the bottom-line.

The Six Sigma Methodology:

The projects having large impact of customer satisfaction and significant impact on bottom-line are selected. Top management of the organization has very important role during selection of projects and leaders. The projects are clearly defined in terms of expected key deliverables. These are typically in terms of DPMO levels or sigma quality levels, RTY, Quality Cost etc. In the overall approach, the actual problem is converted in to a statistical problem. This is done by mapping the process, defining key process input variables (KPIVs or ‘x’s) and key process output variables (KPOVs or ‘y ’s). The power of statistical tools is used to determine a statistical solution. This is then converted in to a practical solution.

Six sigma projects go through four phases:

The number of ‘x’ s go on getting eliminated using various statistical and other tools. This is as if the variation is getting reduced as it passes through a funnel of the six sigma methodology. This is sometimes called the breakthrough strategy.

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Fig 6.2.2

The cause and effects relationship between the KPOVs (‘y’s) and KPIVs (‘x’s) gets clearer as the project goes through the four phases. Control plans are documented before the closure of the project so that gains are sustained. The project leaders must demonstrate that the key deliverables of the project are achieved and demonstrated.

6.3 Strategies for six sigma introduction:

There are three different strategies adopted by different organizations:

1.The six sigma organization

2.The six sigma engineering organization

3.Strategic selection of six sigma projects

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1. The six sigma organization

In this strategy, the whole organization is trained on six sigma philosophy and methods. The training is of varying depth for various levels. Six sigma serves as motivational device and also as a metric. Goals are defined in terms of sigma. While the organization can have a common language of six sigma, large resources are required for training. All improvement ideas are likely to be credited to six sigma regardless of the approach actually used.

2. The Six Sigma Engineering Organization:

Here, the attempt is to develop skills in the Engineering functions. The project objectives are usually based on new products, product changes or problem solving. One of the advantages is the relatively higher level of educational and technical background of the individuals that enables them to learn at a faster pace. On the other hand, individuals from other functions do not appreciate the efforts in absence of the awareness of the techniques.

3. Strategic selection of six sigma projects

The senior management sometimes feels that the current quality processes are generally working well to achieve the overall strategic plan. Hence six sigma tools and concepts are used to enhance the existing quality processes and supplement the skills of the key people thereby making breakthrough improvements. Six sigma projects are identified considering the:

-Strategic direction of the company

-Impact on the bottom-line

-Impact on customer satisfaction

The projects having large impact requires project leaders with high degree of competence. Full time project leaders (sometimes called the Black Belts) are selected to execute the project. Selection of candidates is critical for the success. The project leaders go through in-depth training of six sigma approach and tools and work full time on the project. The project is expected to be completed in about six months. Typical savings expected from a black

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belt project may be of the order of Rs.100, 00000. Projects of lesser complexity may not require full time resource. Project leaders of such projects are chosen from the same functional area. These are sometimes called Green Belts. They also go through training in the six sigma concepts and tools. Training duration is usually less than that for black belts.

This approach requires lesser resources for training that can be customized. The organizations adapting this approach must allocate the best people as project leaders. Some of the potential failure modes of this approach –

-Trained engineers tend to get isolated

-Communication barrier due to lack of common language

-Failure to develop management understanding

7. Criticism on six sigma:

There has been a lot of criticism on six sigma. Many feel that the tools used in the approach have been existing and in reality there is nothing new in sigma In short, six sigma is old wine in new bottle. The criticism is true in a way. However, others feel that while the tools existed earlier, quantification of the metrics and direct relation to the bottom-line makes it somewhat different.

Another major criticism is about the price tag attached to the six sigma training. Typical price tag of a four week black belt course is $ 25000! This is prohibitive for most of the small and medium scale organization. However, training costs may come down in the near future. Another criticism on six sigma is it results in to short term improvement projects. This is countered by its proponents that although one project is of six months duration, the black belts take up next project also train others in six sigma methodology. As more black belts are trained and large number of projects are completed; the organization achieves long term benefits.

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8. Case Study:

Six Sigma Approach to Retail Operational Effectiveness

8.1 Six Sigma DMAIC Approach: Define, Measure, Analyze, Improve, and Control Focus provided the necessary support for the Six Sigma team to implement a much more thorough DMAIC methodology than they had previously been able to conduct.

Fig 8.1.1

Case Study: Six Sigma Approach to Retail Operational Effectiveness

www.iontas.com 4

CONTROL To ensure that the organization remained optimally efficient, the company wisely invested in ongoing training, including quarterly updates and refresher training. They motivated workers to follow the new procedures by offering rewards for achieving best practices. To further enforce best practices, they configured Event Focus to limit access to old practices. Activity Focus continually monitors user activity and ensures schedule adherence while Process Focus monitors process execution. Continued monitoring alerts the team to new or varying processes and to unusual activities.

The improved efficiency in retail operations delivered immediate savings. Executive management predicts $8.5M savings through productivity improvement

in 12 months.

Results The Focus suite gave management the tools they needed to understand exactly what was going on in their retail operations, allowing them to make smart decisions that resulted in an extreme competitive advantage for their Customer Service group. The level of detail

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DEFINE:

Once Focus provided the ability to see how the software applications were used on the desktops, the Six Sigma team looked for repeating patterns and defined those as a process. This ability to visually review repetitive patterns allowed them to effectively recognize 237 unique processes used within their institution, which would not have been possible without the visual insight of Activity Focus.

MEASURE

Once the team defined the processes, they analyzed process performance metrics based on geography, demographics of the workers, and size of the location. They discovered the best performers and learned how these workers were more effective than the others. They also uncovered training issues,unexpected compliance variations, and obsolete software that exposed previously-hidden costs. The team was then able to define and profile an ideal worker based on demographic analysis and best practices.

ANALYZE

With facts in hand, the Six Sigma team was able to measure standard procedures against deviating procedures to determine the root causes for the workers’ variant execution styles. They implemented Process Focus to monitor and analyse process execution.

IMPROVE

Once best practices had been defined, the Six Sigma team developed an improvement plan to reduce the hidden software costs, define standard policies and procedures, and invest in training initiatives to deploy best practices throughout the 55,000 workers. Utilizing Event Focus, the process re-engineering team introduced just-in- time prompts and real-time alerts to guide users through tasks, not only improving efficiency but also increasing up-sell and cross sell- opportunities within the organization.

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CONTROL

To ensure that the organization remained optimally efficient, the company wisely invested in ongoing training, including quarterly updates and refresher training. They motivated workers to follow the new procedures by offering rewards for achieving best practices. To further enforce best practices, they configured Event Focus to limit access to old practices. Activity Focus continually monitors user activity and ensures schedule adherence while Process Focus monitors process execution. Continued monitoring alerts the team to new or varying processes and to unusual activities.

Results

The Focus suite gave management the tools they needed to understand exactly what was going on in their retail operations, allowing them to make smart decisions that resulted in an extreme competitive advantage for their Customer Service group. The level of detail and depth of the information available through the Focus software suite enabled insight into the very root causes of their problems.

Variation defines the ”sigma” level

Why is variation important ? For example , a customer expecting delivery “by noon”(the target) might actually be happy if the package arrives anywhere from 11 a.m. to 1 p.m. A manufacturer that is purchasing 1000 gallons of paint (the target),might be satisfied if the delivery is 995 to 1005 gallons.(In manufacturing ,the range of acceptable values is usually called specifications.).

Anything that does not meet the customer need is a “defect” when you compare the product process performance against what customer wants ,you can see that the process with a lot of variation ,your customer will view them as unpredictable .Sometimes they’ll get what they want , but a lots of times they won’t.

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Fixing the process is what improves sigma level

Now here’s one of the secret of lean six sigma : in order to have an outcome with very little variation ,everything leading to that point has to work well, too .This explains why lean six sigma focuses so much on process improvement .You need to make your work in your area more reliable, more predictable to reach high levels of quality – which means eliminating variations .

8.2 FedEx

For a real example of how business can capitalize on reduced variations, just think about FedEx.It created a new industry because of its ability to reliably meet promised delivery dates. If their guarantee of 10:00 a.m. delivery have really meant “anytime tomorrow”, how long do you think they would have stayed in business ? People keep coming back because they can count on having their packages delivered by the guarantee time. FedEx’s experience also shows that reducing variation is something that both service and manufacturing business should focus on .

8.3 Dhabbawala

Mumbai is a very densely populated city of millions with huge flows of traffic. Because of this, lengthy commutes to workplaces are common, with many workers traveling by train.

Instead of going home for lunch or paying for a meal in a café, many office workers have a cooked meal sent either from their home, or sometimes from a caterer who essentially cooks and delivers the meal in lunch boxes and then have the empty lunch boxes collected and re-sent the same day. This is usually done for a monthly fee. The meal is cooked in the morning and sent in

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lunch boxes carried by dabbawalas, who have a complex association and hierarchy across the city.

Fig 8.3.1

Dabbawalas in action at a Mumbai Suburban Railway station.

A collecting dabbawala, usually on bicycle, collects dabbas either from a worker's home or from the dabba makers. The dabbas have some sort of distinguishing mark on them, such as a colour or symbol.

The dabbawala then takes them to a designated sorting place, where he and other collecting dabbawalas sort (and sometimes bundle) the lunch boxes into groups. The grouped boxes are put in the coaches of trains, with markings to identify the destination of the box (usually there is a designated car for the boxes). The markings include the rail station to unload the boxes and the building address where the box has to be delivered.

At each station, boxes are handed over to a local dabbawala, who delivers them. The empty boxes, after lunch, are again collected and sent back to the respective houses.

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Fig 8.3.2

A collecting Dabbawala on a bicycle

In 2002, Forbes Magazine found its reliability to be that of a six sigma standard. More than 175,000 or 200,000 lunch boxes get moved every day by an estimated 4,500 to 5,000 dabbawalas, all with an extremely small nominal fee and with utmost punctuality. According to a recent survey, they make less than one mistake in every 6 million deliveries, despite most of the delivery staff being illiterate.

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9. Concluding Remarks:

Six sigma is powerful approach achieve breakthrough improvements in manufacturing, engineering and business processes. The approach relies heavily on advanced statistical methods that complement the process and product knowledge to reduce variation in processes. It is new way of doing business that would eliminate the existing defects efficiently and would prevent defects from occurring. Different strategies are used by organizations to introduce and deploy six sigma approach. Each of these strategies has advantages and potential failure modes that must be addressed and avoided.

Six Sigma looks as though it is here to stay and even in today’s slow economy one of the few areas where there still are a number of new positions. The Six Sigma process is a great step toward creating learning organizations with its well-defined roadmaps and management structure. As with most new methodologies Six Sigma will mature and grow as it expands into new areas such as DFSS. As Six Sigma professionals learn more about the power of properly planned experiments, Design of Experiments will be integrated into most phases of the Six Sigma roadmap and not just considered an advanced tool for the improvement and optimization phases. Experienced practitioners of statistical methods like Design of Experiments should learn the language of Six Sigma and help integrate new methods into the Six Sigma process to improve its effectiveness.

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10. Reference:

10.1 Journals.

• Quality & Productivity Journal : September 2000 Issue Mr. Hemant Urdhwareshe, C.Q.Mgr., C.Q.E. (ASQ)

10.2 Books.

• What is LEAN SIX SIGMA?,Mike George,Dave Rowlands,&Bill Kastle.Tata McGraw-Hill Edition 2004

• Design for Six Sigma-A Roadmap for Product Development by Kai Yang Basem El-Haik

10.3 Website.

• http://www.symphonytech.com/articles/pdfs/sixsigma.pdf last visited on 15.8.2011

• http://www.iontas.com/documents/Iontas%20Case%20Study-Six%20Sigma%20Retail.pdf last visited on 24.8.2011

• http://www.sixsigmadigest.com/support-files/six-sigma-methodology-roadmap.pdf

• http://www.sixsigmaonline.org/six-sigma-training-certification-information/articles/the-new-scope-and-breadth-of-six-sigma-methodology.html