Six sigma

Presented by: Ayush Shakya

Neeti Kumar Rashmikat Jha

BFT- V (2011-15)

Introduction to

3.4 defects per million opportunities

Philosophy that changes the way of thinking within a

company

Business strategy that brings a company to

competitive edge

Business Improvement Methodology

What is Six Sigma?

2Introduction to Six Sigma

Defect reduction

Yield improvement

Improved customer satisfaction

Higher net income

Continual improvement

What does Six Sigma mean practically?


Carl Frederick Gauss ( 1777-1855) introduced the concept of

the normal curve

As a measurement standard in 1920’s, Walter Shewhart

showed three sigma is the point from the mean where a

process requires correction

1970’s: Mikel Harry, a senior staff engineer at Motorola’s

Government Electronics Group began to formulate a method

for applying six sigma throughout Motorola

Six Sigma Evolution


In 1987 when Bob Galvin was the Chairman , Six Sigma

was started as a methodology in Motorola.

Bill smith , an engineer, and Mikel Harry together devised

a 6 step methodology with the focus on defect reduction

and improvement in yield through statistics

The term “Six Sigma” was coined by Bill Smith, who is now

called Father of Six Sigma

The company saved $ 16 billion in 10 years.

History of Six Sigma: Motorola


History of Six Sigma


Introduction to Six Sigma 7

Performing at sigma level of six means that difference

between mean and specific limit is six times the

standard deviation.

Six Sigma

Generated as a result of a process experiencing random

variation

Characterized by mean and standard deviation

The Normal Distribution



Measuring variation using standard deviation

Objective of Six Sigma

Sigma Level DPMO

2 308,537

3 66,807

4 6,210

5 233

6 3.4

99.99966% good- sigma level of 6


Customer-centered

Process-focused

Data Driven

Big Performance Gains

Structured improvement deployment

Validation through key business results, ( financial

gains in most cases)

Characteristics of Six Sigma


What is Six Sigma Performance? 99% Good (3.8s)

• 5,000 incorrect

operations per week

• Two short or long

landings at most major

airports each day

• 200,000 wrong drug

prescriptions each year

99.99966% Good (6s)

• 1.7 incorrect

operations per week

• One short or long

landing every five

years

• 68 wrong

prescriptions per year.


Six Sigma : The Projects

• Projects are linked to the Strategic Plan

• Projects prioritized based on value to the business, resources

required, and timing

– Yield improvement

– Waste reduction

– Capacity-productivity improvement

– Cycle time reduction

• Projects are formally tracked

• Team Leader and Management are held accountable


Six Sigma Improvement Methodology D-M-A-I-C

PLAN

DOCHECK

ACT

Define

Measure

AnalyzeImprove

Control


DMAIC Steps

• Identify projects that are measurable

• Define projects including the demands of the customer

and the content of the internal process.

• Develop team charter

• Define process map

1. Define 2. Measure 3. Analyze 4. Improve 5. Control


DMAIC Steps

• Define performance standards

• Measure current level of quality into Sigma. It

precisely pinpoints the area causing problems

• Identify all potential causes for such problems

5.0Control

2. Measure1. Define 3. Analyze 4. Improve 5. Control


DMAIC Steps

3.0 Analyze

3. Analyze1. Define 2. Measure 4. Improve 5. Control

• Establish process capability

• Define performance objectives

• Identify variation sources

• Screen potential causes

• Discover variable relationships among causes and

effects



DMAIC Steps

• Hypothesis Testing

• Regression Analysis

• Box Plot

• Correlation

• Regression

• Process Mapping

• Failure Mode & Effect Analysis

• Design of Experiments

• Control charts

• Quality Function Deployment

(QFD)

3. Analyze1. Define 2. Measure 4. Improve 5. Control

DMAIC Steps

• Establish operating tolerances

• Pursue a method to resolve and ultimately eliminate

problems. It is also a phase to explore the solution

how to change, fix and modify the process.

• Carryout a trial run for a planned period of time to

ensure the revisions and improvements implemented

in the process result in achieving the targeted values.

4. Improve1. Define 2. Measure 3. Analyze 5. Control


DMAIC Steps

• Monitor the improved process continuously to ensure

long term sustainability of the new developments.

• Share the lessons learnt

• Document the results and accomplishments of all the

improvement activities for future reference.

5. Control1. Define 2. Measure 3. Analyze 4. Improve

Control Charts:

Assigning clear process ownership and documenting 20Introduction to Six Sigma

Flowchart of DMAIC process


Key Terms

Y’s• Key process output variable • Thought of in terms of performance/defect measures X’s• Key process input variable • Are a list of variables that influence the response(s) or

Y’s• Y is a function of the X’s or

Y = f(X1, X2, …)

The goal of six sigma is to understand the X’s that control the Y’s.


x

x

x

Y = f(X1, X2, …)

Suppliers Customers

X’s, Inputs• Process variables• Inputs to the process• Essential actions to

achieve strategic goals• Key influences on

customer satisfaction

Y’s, Outputs• Customer requirements• Yield, Waste, Rate• On Time Delivery• Economic Profit• Strategic goal • Customer satisfaction

Process

Inputs Outputs


Sigma level calculation

DPMO = DPU * 1,000,000 / OFE• DPMO – Defects per million opportunities

• DPU – defects per unit

= No. of defects / No. of pieces inspected

• OFE – Opportunities for error per unit

= No. of characteristics inspected per unit

Sigma level = Value of Zst from the Sigma level and DPMO table





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Education

Six sigma