Quality tools2

The Basic Seven (B7) The Basic Seven (B7) Tools of QualityTools of Quality

A PowerPoint Training A PowerPoint Training PresentationPresentation

By Keith H. CooperBy Keith H. Cooper

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

What are the Basic What are the Basic Seven Tools of Quality?Seven Tools of Quality?

• Fishbone DiagramsFishbone Diagrams• HistogramsHistograms• Pareto AnalysisPareto Analysis• FlowchartsFlowcharts• Scatter PlotsScatter Plots• Run ChartsRun Charts• Control ChartsControl Charts

Where did the Basic Where did the Basic Seven come from?Seven come from?

Kaoru IshikawaKaoru Ishikawa• Known for “Democratizing Statistics”Known for “Democratizing Statistics”

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

• Good Visual Aids make statistical and Good Visual Aids make statistical and quality control more comprehendible.quality control more comprehendible.


Fishbone DiagramsFishbone Diagrams

• No statistics involvedNo statistics involved

• Maps out a process/problemMaps out a process/problem

• Makes improvement easierMakes improvement easier

• Looks like a “Fish Skeleton”Looks like a “Fish Skeleton”

Constructing a Fishbone Constructing a Fishbone DiagramDiagram

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

Example: Example: High Inventory Shrinkage at local Drug High Inventory Shrinkage at local Drug StoreStore

Shrinkage

Constructing a Constructing a Fishbone DiagramFishbone Diagram

• Step 3 - Identify different areas where Step 3 - Identify different areas where problems may arise fromproblems may arise from

Ex. : Ex. : High Inventory Shrinkage at local Drug StoreHigh Inventory Shrinkage at local Drug Store

Shrinkage

employees

shoplifters

Constructing a Constructing a Fishbone DiagramFishbone Diagram

• Step 4 - Identify what these specific Step 4 - Identify what these specific causes could becauses could be

Ex. : Ex. : High Inventory Shrinkage at local Drug StoreHigh Inventory Shrinkage at local Drug Store

Shrinkage

shoplifters

Anti-theft tags poorly designedExpensive merchandise out in the open

No security/ surveillance


• Ex. : Ex. : High Inventory Shrinkage at local Drug StoreHigh Inventory Shrinkage at local Drug Store

Shrinkage

shoplifters

Anti-theft tags poorly designedExpensive merchandise out in the open

No security/ surveillance

employeesattitude

new traineetraining

benefits practices


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


HistogramsHistograms

• Bar chartBar chart

• Used to graphically represent groups Used to graphically represent groups of dataof data

ConstructingConstructing a Histogram a Histogram

From a set of data computeFrom a set of data compute• sumsum• mean (x)mean (x)• MaxMax• MinMin• Range (max-min)Range (max-min)

ConstructingConstructing a Histogram a Histogram

• Use range to estimate beginning Use range to estimate beginning and end and end

• Calculate the width of each Calculate the width of each column by dividing the range by column by dividing the range by the number of columnsthe number of columns

Range

# of Columns= Width

Acme Pizza ExampleAcme Pizza Example

• Let’s say the owner wants a Let’s say the owner wants a distribution of Acme’s Thursday distribution of Acme’s Thursday Night SalesNight Sales

Data Set from last Thursday(slices)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 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 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 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 41 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


Mean = 2.032258 Mean = 2.032258 Max = 7 Max = 7 Min = 0 Min = 0 Range = 7 Range = 7

QuestionQuestionFor 7 columns what would the width For 7 columns what would the width

be?be? Range/Columns=7/7=1 slice


33

65

812

0 0 10

10

20

30

40

50

60

70

1 2 3 4 5 6 7

Slices of Pizza

# tim

es o

r der

edHistogram

Constructing a HistogramConstructing a Histogram

How is this helpful to Acme?How is this helpful to Acme?• 2 slices of pizza most common order 2 slices of pizza most common order

placedplaced• Distribution of sales useful for Distribution of sales useful for

forecasting next Thursday’s late forecasting next Thursday’s late night demandnight demand

If you were an Acme manager how If you were an Acme manager how could you apply this information?could you apply this information?


Pareto AnalysisPareto Analysis

• Very similar to HistogramsVery similar to Histograms

• Use of the 80/20 ruleUse of the 80/20 rule

• Use of percentages to show Use of percentages to show importanceimportance

Acme Pizza (part 2)Acme Pizza (part 2)SlicesSlices FrequencyFrequency %% 00 11 .3.3

11 33 33 13.09 13.0922 65 65 25.79 25.7933 88 3.17 3.1744 12 12 4.76 4.7655 00 0066 00 0077 11 .3 .3

Acme Pizza (part 2)Acme Pizza (part 2)• The completed Pareto Analysis results in the The completed Pareto Analysis results in the

following graph:following graph:

0

10

20

30

40

50

60

70

1 2 3 4 5 6 7

Slices of Pizza

# tim

es o

r der

ed

2 1 4 3 7 5 6

Acme Pizza (part 2)Acme Pizza (part 2)

Critical ThinkingCritical Thinking• How does the Pareto Analysis How does the Pareto Analysis

differ from the Histogram?differ from the Histogram?

• How can this be a useful tool to How can this be a useful tool to the Acme boss?the Acme boss?


FlowchartsFlowcharts

• A graphical picture of a PROCESSA graphical picture of a PROCESS

Process Decision

The process flow

FlowchartsFlowcharts

Don’t Forget to:Don’t Forget to:

• Define symbols before beginningDefine symbols before beginning

• Stay consistentStay consistent

• Check that process is accurateCheck that process is accurate

Acme Pizza Example Acme Pizza Example (Flowchart)(Flowchart)

WindowWindow Take CustomerTake Customer Money?Money? (start)(start) Order Order

Get PizzaGet Pizza

LockupLockupPut More inPut More in OvenOven 2 Pies 2 Pies Available?Available?

TimeTime

to close?to close? Take to CustomerTake to Customer

noyes

no

yesno

yes

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

the Histogram?the Histogram?

WindowWindow Take CustomerTake Customer Money?Money? (start)(start) Order Order

Get PizzaGet Pizza

LockupLockupPut More inPut More in OvenOven 2 Pies 2 Pies Available?Available?

TimeTime

to close?to close? Take to CustomerTake to Customer

noyes

no

yesno

yes

Want some practice?Want some practice?Make a flowchart for:Make a flowchart for:

• Taking a showerTaking a shower• Cooking dinnerCooking dinner• Driving a carDriving a car• Having a partyHaving a party• Creating a FlowchartCreating a Flowchart

Any other processes you can think of?Any other processes you can think of?


Scatter PlotsScatter Plots• 2 Dimensional X/Y plots2 Dimensional X/Y plots• Used to show relationship Used to show relationship

between independent(x) and between independent(x) and dependent(y) variablesdependent(y) variables

Acme Pizza Acme Pizza (Scatter Diagram)(Scatter Diagram)

Minutes CookingMinutes Cooking Defective Pies Defective Pies1010 114545 883030 557575 20 206060 14 142020 442525 66

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

Scatter DiagramsScatter Diagrams

0

5

10

15

20

25

0 20 40 60 80

•Easier to see direct relationship

Time Cooking (minutes)

Def

ect i

ve P

i zza

s

Scatter DiagramsScatter Diagrams

As a quality toolAs a quality tool• What does this tell Acme What does this tell Acme

management about their management about their processes?processes?

• Improvements?Improvements?

0

5

10

15

20

25

0 20 40 60 80

Time Cooking (minutes)

Def

e cti

v e P

i zza

s


Run chartsRun charts• Time-based (x-axis)Time-based (x-axis)

• CyclicalCyclical

• Look for patternsLook for patterns

Run ChartsRun 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

5 10

15

20 2

5 30

35

40 4

5 50

55

60 6

5 70

75

80 8

5 90

95

100

Slices/hour

Time


Control ChartsControl Charts• Deviation from MeanDeviation from Mean

• Upper and Lower Spec’sUpper and Lower Spec’s

• RangeRange

Control ChartsControl ChartsUpper LimitUpper Limit

Lower LimitLower LimitUnacceptable deviation

X

Control ChartsControl ChartsAcme 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 Acme example Control ChartsControl Charts

Upper LimitUpper Limit17 inches17 inches

Lower LimitLower Limit15 Inches15 Inches

Small Pie

X16 inches=

Acme example #50Acme example #50Control ChartsControl Charts

•Pies within specifications were acceptable

•One abnormally small pie is “uncommon”

•Should be examined for quality control

SummarySummary• Basic Seven Tools of QualityBasic Seven Tools of Quality

• Measuring dataMeasuring data

• Quality AnalysisQuality Analysis

• ““Democratized statistics”Democratized statistics”

BibliographyBibliography

• Foster, Thomas. Foster, Thomas. Managing Quality. An Integrative Managing Quality. An Integrative ApproachApproach. Upper Saddle River : Prentice Hall, . Upper Saddle River : Prentice Hall, 2001.2001.

• Stevenson, William. “Supercharging Your Pareto Stevenson, William. “Supercharging Your Pareto Analysis.” Analysis.” Quality ProgressQuality Progress October 2000: October 2000: 51-55.51-55.

• ““Dr Kaoru Ishikawa.” Internet Dr Kaoru Ishikawa.” Internet “http://www.dti.gov.uk/mbp/bpgt/m9ja00001/m9j“http://www.dti.gov.uk/mbp/bpgt/m9ja00001/m9ja0000110.html.” 16 February 2001.a0000110.html.” 16 February 2001.

• ““Chemical and Process Engineering.” Internet. Chemical and Process Engineering.” Internet. “http://lorien.ncl.ac.uk/ming/spc/spc8.htm.” 17 “http://lorien.ncl.ac.uk/ming/spc/spc8.htm.” 17 February February 2001.2001.

Quality tools2

Technology

Transcript of Quality tools2