7 qc tool presentation material

Spirit Proprietary 1

7 QC TOOLS

The term “7 QC tools for QC” is name after the 7 tools of the famous warrior , Benkai. Benkai owned 7 weapons, which he used to win all his battles. Similarly, from my own experience, you will find that you will able to solve 95% of the problems around you if you wisely use the 7 tools of QC.” ISHIKAWA KAORU, Professor Emeritus, University of Tokyo.

7 Quality Tools


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IntroductionIn 1950, the Japanese Union of Scientists and Engineers (JUSE) invited legendary quality guru W. Edwards Deming to go to Japan and train hundreds of Japanese engineers, managers and scholars in statistical process control. Deming also delivered a series of lectures to Japanese business managers on the subject, and during his lectures, he would emphasize the importance of what he called the "basic tool" that were available to use in quality control.

One of the members of the JUSE was Kaoru Ishikawa, at the time an associate professor at the University of Tokyo. Ishikawa had a desire to 'democratise quality': that is to say, he wanted to make quality control comprehensible to all workers, and inspired by Deming’s lectures, he formalised the Seven Basic Tools of Quality Control.

Ishikawa believed that 90% of a company’s problems could be improved using these seven tools, and that –- with the exception of Control Charts -- they could easily be taught to any member of the organisation. This ease-of-use combined with their graphical nature makes statistical analysis easier for all.


The Basic Seven (B7) Tools of Quality

A PowerPoint Training Presentation

"As much as 95% of quality related problems in the factory can be solved with seven fundamental quantitative tools." - Kaoru

Ishikawa


What are the Basic Seven Tools of Quality?

1 – Fishbone/Ishikawa Diagrams 2 - Histograms 3 - Pareto Analysis 4 - Flowcharts 5 - Scatter Plots 6 - Run Charts 7 - Control Charts


Where did the Basic Seven come from?

Kaoru Ishikawa Known for “Democratizing Statistics”

The Basic Seven Tools made statistical analysis less complicated for the average person

Good Visual Aids make statistical and quality control more comprehendible.



1] Fishbone Diagrams

No statistics involved

Maps out a process/problem

Makes improvement easier

Looks like a “Fish Skeleton”


Constructing a Fishbone Diagram

Step 1 - Identify the Problem Step 2 - Draw “spine” and “bones”

Example: High Inventory Shrinkage at local Drug Store

Shrinkage



Step 3 - Identify different areas where problems may arise from

Ex. : High Inventory Shrinkage at local Drug Store

Shrinkage

employees

shoplifters



Step 4 - Identify what these specific causes could be


Shrinkage

shoplifters

Anti-theft tags poorly designedExpensive merchandise out in the open

No security/ surveillance




Shrinkage

shoplifters

Anti-theft tags poorly designedExpensive merchandise out in the open

No security/ surveillance

employeesattitude

new trainee

training

benefits practices



Step 5 – Use the finished diagram to brainstorm solutions to the main problems.



2] Histograms

Bar chart

Used to graphically represent groups of data


Constructing a Histogram

From a set of data compute sum mean (x) Max Min Range (max-min)


Constructing a Histogram

Use range to estimate beginning and end Calculate the width of each column by

dividing the range by the number of columns

Range

# of Columns

= Width


Pak Mat Pizza Example

Let’s say the owner wants a distribution of Pak Mat’s Thursday Night Sales

Data Set from last Thursday(slices)0 2 1 2 2 4 1 3 1 2 1 2 2 4 3 4 1 4 3 2 2 3 2 1 2 2 1 2 2 1 4 2 2 1 2 1 2 2 1 2 1 2 1 2 1 2 1 2 1 2 2 2 1 2 1 2 1 1 2 2 2 3 1 4 2 2 3 2 2 2 1 2 3 2 2 4 2 2 4 4 1 2 2 2 3 2 2 1 2 2 4 2 1 2 4 2 1 7 2 1 2 2 3 1 2 1 1 2 1 2 2 2 1 2 2 1 2 1 2 2 2 4 2 4


Acme Pizza ExampleMean = 2.032258 Max = 7 Min = 0 Range = 7

QuestionFor 7 columns what would the width be?

Range/Columns=7/7=1 slice


Pak Mat Pizza Example

33

65

812

0 0 10

10

20

30

40

50

60

70

1 2 3 4 5 6 7

Slices of Pizza

Histogram


Constructing a HistogramHow is this helpful to Pak Mat? 2 slices of pizza most common order placed Distribution of sales useful for forecasting

next Thursday’s late night demand

If you were an Pak Mat manager how could you apply this information?



3] Pareto Analysis

Very similar to Histograms

Use of the 80/20 rule

Use of percentages to show importance


Pak Mat Pizza (part 2)

Slices Frequency %0 1 .31 33 13.092 65 25.793 8 3.174 12 4.765 0 06 0 07 1 .3



The completed Pareto Analysis results in the following graph:

0

10

20

30

40

50

60

70

1 2 3 4 5 6 7

Slices of Pizza

2 1 4 3 7 5 6



Critical Thinking How does the Pareto Analysis differ

from the Histogram?

How can this be a useful tool to the Pak Mat boss?



4] Flowcharts

A graphical picture of a PROCESS

Process Decision

The process flow


FlowchartsDon’t Forget to:

Define symbols before beginning

Stay consistent

Check that process is accurate


Pak Mat Pizza Example (Flowchart)

Window Take Customer Money?(start) Order

Get PizzaLockup

Put More inOven 2 Pies

Available?

Timeto close?

Take to Customer

noyes

no

yesno

yes


How can we use the flowchart to analyze improvement ideas from the Histogram?

Window Take Customer Money?(start) Order

Get PizzaLockup

Put More inOven 2 Pies

Available?

Timeto close?

Take to Customer

noyes

no

yesno

yes


Want some practice?

Make a flowchart for:

Taking a shower Cooking dinner Driving a car Having a party Creating a Flowchart

Any other processes you can think of?



5] Scatter Plots

2 Dimensional X/Y plots Used to show relationship between

independent(x) and dependent(y) variables


Pak Mat Pizza (Scatter Diagram)

Minutes Cooking Defective Pies10 145 830 575 2060 1420 425 6

In this simple example, you can find the existing relationship without much difficulty but…


Scatter Diagrams

0

5

10

15

20

25

0 20 40 60 80

•Easier to see direct relationship

Time Cooking (minutes)


Scatter Diagrams

As a quality tool What does this tell Pak Mat

management about their processes? Improvements?

0

5

10

15

20

25

0 20 40 60 80

Time Cooking (minutes)



6] Run charts Time-based (x-axis)

Cyclical

Look for patterns


Run Charts

8 9 10 11 12 1 2 3 4

8 9 10 11 12 1 2 3 4

8 9 10 11 12 1 2 3 4PM- AM PM- AM PM- AM

Thursday

Week 1

Thursday

Week 2

Thursday

Week 3

Slices/hour

Time



7] Control Charts Deviation from Mean

Upper and Lower Spec’s

Range


Control ChartsUpper Limit

Lower Limit

Unacceptable deviation

X


Control Charts

Pak Mat Pizza Management wants to get in on the control chart action

•Average Diameter = 16 inches

•Upper Limit = 17 inches

•Lower Limit = 15 inches


Acme example Control Charts

Upper Limit17 inches

Lower Limit15 Inches

Small Pie

X16 inches=


Pak Mat example #50Control Charts

•Pies within specifications were acceptable

•One abnormally small pie is “uncommon”

•Should be examined for quality control


Summary Basic Seven Tools of Quality

Measuring data

Quality Analysis

“Democratized statistics”


Bibliography

Foster, Thomas. Managing Quality. An Integrative Approach. Upper Saddle River : Prentice Hall, 2001.

Stevenson, William. “Supercharging Your Pareto Analysis.” Quality Progress October 2000: 51-55.

“Dr Kaoru Ishikawa.” Internet “http://www.dti.gov.uk/mbp/bpgt/m9ja00001/m9ja0000110.html.” 16 February 2001.

“Chemical and Process Engineering.” Internet. “http://lorien.ncl.ac.uk/ming/spc/spc8.htm.” 17 February 2001.