six sigma and lean thinking

7/31/2019 Six Sigma and Lean Thinking

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Six Sigma and Lean thinking

Miguel Lopez

M&D Consulting Agency


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Agenda

Six Sigma

Introduction

Symbols

Definitions

The k*sigma importance

Example

Organizational levels

Lessons learned


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Agenda

Six Sigma

Introduction

Vision

Definitions

Quote

Lessons learned


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SIX SIGMA


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Introduction Six Sigma

What is a process?

What is Quality Control?

What means to say, a process quality isin control?

What is a normal distribution?

What is Sigma? What is a manufacturers specification

limit?


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Symbols

Standard deviation =

Average =

Normal distribution = N(,)


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Definitions

Sigma is:

The square root of the

variance

What sigma means isthe

1

n

i

Xi

2

n


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Definitions cont.

Normal distribution

= 0

= 1

Blue is N(0,1)

Red is cummulative

N(0,1)

Green, brown, and pinkis 1, 2, and 3

distances respectively 4 2 0 2 40

0.2

0.4

0.6

0.8


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Definition cont.

Specification limit

It is the range of values considered

acceptable in the manufacturing of a

specific product for a specific characteristic.

Six Sigma

To accommodate six times the standard

deviation value in between themanufacturers specification limits


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Definitions cont.

The universal formula k


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The k*sigma importance

K Probability ARL nonconforming1 0.841344746068543 6.30

1.5 0.933192798731142 14.97

2 0.977249868051821 43.96

2.5 0.993790334674224 161.04

3 0.998650101968370 740.80

3.5 0.999767370920966 4,298.69

4 0.999968328758163 31,574.39

4.5 0.999996602326866 294,319.07

5 0.999999713348346 3,488,554.79

5.5 0.999999981010436 52,660,502.10

6 0.999999999013412 1,013,594,634.896.5 0.999999999959840 24,900,406,809.35

7 0.999999999998720 781,332,343,402.24

7.5 0.999999999999968 31,383,969,528,714.30

8 0.999999999999999 1,501,199,875,790,170.00


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Example

Extrusion of plastic

Assume we are interested in a plastic

extrusion process. We can control the

temperature at which the plastic is meltedand the rate of extrusion.

The manufacturers limits are +/-2mm

The actual situation is represented in thenext slide.


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Example cont.

= 0

= 1

USL = 2

LSL = -2

4 2 0 2 40

0.2

0.4

0.6

0.8


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Example cont.

What can we do to improve the process?

Reduce the variance thereby reducing

the standard deviation.

How?

Slow the extrusion rate.


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Example cont.

4 2 0 2 40

0.2

0.4

0.6

0.8

= 2

= .5

USL = 2

LSL = -2


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Example cont.

What can we do to improve the process?

Modify something else

What? The melting temperature.

How?

A higher temperature.


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Example cont.

4 2 0 2 40

0.2

0.4

0.6

0.8

= -1

= 1.5

USL = 2

LSL = -2


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Example cont.

Still wrong. What next?

We have to continue trying differentcombinations

Ej. High temperature and high extrusion rate

High temperature and low extrusion rate

Low temperature and high extrusion rate

Low temperature and low extrusion rate

Change the type of plastic

Among others


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Example cont.

The answer

should look

in the end

somethinglike this.

4 2 0 2 40

.2

.4

.6

.8


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Lessons learned

Six Sigmadoes nothave a unique wayof solving problems in the industry.

It requires experimentation, studies, and good

applied Engineering to solve the problems. Six Sigma is a tool that if applied correctly the

quality of the product is guaranteed by

showing if non-conforming products are going

to happen or not.


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Organizational levels

Since Six Sigma is very famous and it is

one the fashion statements in the industry,

levels have been made to differentiate

how much knowledge a person has in sixsigma

Green belt

Black belt

Master black belt


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Organizational levels cont.

Green belt Black belt


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Organizational levels cont.

Master black belt


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Lean Thinking


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Introduction

What are constraints?

What is efficiency?

What is productivity? What is added value?

What is cost efficient?

What is lean? What is thinking?


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Vision


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Definitions


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Quote

Common sense is

the least common

of senses.

Jos Duprey


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Lessons learned


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QUESTIONS?????

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