7 - quality tools

Honda of the UK Manufacturing Ltd.Honda of the UK Manufacturing Ltd.

NH Circle Programme TrainingNH Circle Programme Training

Quality ToolsQuality Tools

Quality Tools - Deming Control CircleQuality Tools - Deming Control Circle

• Schedule work with a clear purpose.Schedule work with a clear purpose.

• Carry out every day procedures & confirm.Carry out every day procedures & confirm.

• If results show deviation from schedule:If results show deviation from schedule:

- Modify Procedure- Modify Procedure

- Or, if required modify schedule.

• Activities for achieving purpose & target Activities for achieving purpose & target are referred to asare referred to as

• The The ‘CONTROL’‘CONTROL’ activities are carried out activities are carried out in 4 stages called thein 4 stages called the

• To carry out any task ensure you use the To carry out any task ensure you use the ‘ ‘ CONTROL CIRCLE CYCLE (P-D-C-A)’.CONTROL CIRCLE CYCLE (P-D-C-A)’.

‘‘CONTROL’CONTROL’

‘CONTROL CIRCLE’.


• PlanPlan

• DoDo

• CheckCheck

• ActionAction

PP

DD

AA

CC

Aim is continuous improvementAim is continuous improvement


Whenever you need to check a concern Whenever you need to check a concern always ask the 5W’s & 2 H’salways ask the 5W’s & 2 H’s

• HOWHOW• WHY WHY

• WHERE WHERE

• WHATWHAT

• WHENWHEN

• WHOWHO

5 W’S5 W’S 2 H’S2 H’S

• HOW MANYHOW MANY

Quality Tools – 5 W’s & 2 H’sQuality Tools – 5 W’s & 2 H’s

To fully understand any concern &To fully understand any concern & implement any improvement, it is first implement any improvement, it is first

necessary to observenecessary to observe

- Go to the - Go to the Actual LocationActual Location• GENBAGENBA

• GENBUTSUGENBUTSU

• GENJITSUGENJITSU

- Look at the Look at the Actual Product Actual Product or or concernconcern

- See the - See the Actual SituationActual Situation

Quality Tools – 3 GensQuality Tools – 3 Gens

Information to begin the Flowchart• A pictorial view A pictorial view

to help you to help you understand understand how processes how processes or activities or activities flow.flow.

Review

End or break to

begin new Flowchart

Decision

Points

Tasks during the process

NO

Document

YES

• Starting point to Starting point to simplify a process.simplify a process.

Quality Tools – FlowchartsQuality Tools – Flowcharts

• Determine start, end & boundaries.Determine start, end & boundaries.

• Brainstorm list of all steps.Brainstorm list of all steps.

• List all inputs, outputs & decision points.List all inputs, outputs & decision points.

Quality Tools – Flowchart StepsQuality Tools – Flowchart Steps

• Arrange steps in order they occur. Arrange steps in order they occur.

• Make sure sequence is exactly as it happens.Make sure sequence is exactly as it happens.

• Use post-it notes to ease moves & additions.Use post-it notes to ease moves & additions.

• Draw the flow using the symbols & arrows.Draw the flow using the symbols & arrows.

• Keep level of detail constant.Keep level of detail constant.

• Use normal language & avoid jargon.Use normal language & avoid jargon.

• Add title, author’s name & date of preparation.Add title, author’s name & date of preparation.

Quality Tools – Flowchart StepsQuality Tools – Flowchart Steps

• Test Flowchart (process, symbols & arrows).Test Flowchart (process, symbols & arrows).

• Check it out on someone not involved.Check it out on someone not involved.

• Finalise & draw the ideal Flowchart.Finalise & draw the ideal Flowchart.

Need Need a new a new car car

Still want carStill want car

New CarNew Car

Sales Sales LiteratureLiterature

CurrentCurrentPrice Price ListList

Collect &Collect &Examine Examine brochuresbrochures

BB

Visit showroom Visit showroom test & negotiatetest & negotiate

BB

SS

Buy the Buy the carcar

YESYESBB

SS

Analyse Analyse Price &Price & optionsoptions

BB

OUTPUTOUTPUT

INPUTINPUT

Prepared by: J SmithPrepared by: J SmithDate: 13 March 2002Date: 13 March 2002

KEY TO KEY TO RESPONSIBILITYRESPONSIBILITY

B = BuyerB = Buyer S = SalespersonS = Salesperson

Flowchart Example - Buying a CarFlowchart Example - Buying a Car

NONO

Flowchart – One for you to try!Flowchart – One for you to try!From the description of the game of craps below, create a flowchart From the description of the game of craps below, create a flowchart

1.1. First lay out your stake, then throw the dice.First lay out your stake, then throw the dice.

2.2. If you throw a 7 or 11 on the first roll, you win, and you get to roll If you throw a 7 or 11 on the first roll, you win, and you get to roll again. If you throw 2 or 12 you loose, this is called ‘crapping out’.again. If you throw 2 or 12 you loose, this is called ‘crapping out’.

3.3. Whenever you loose you must pass the dice. Whenever you loose you must pass the dice.

4.4. If you throw any number other than 2, 7, 11 or 12, you get to throw If you throw any number other than 2, 7, 11 or 12, you get to throw again to try to ‘make your point’, i.e. throw that same number again to try to ‘make your point’, i.e. throw that same number again. For example, if you throw a 4, then roll again trying to again. For example, if you throw a 4, then roll again trying to make another 4. If you don’t throw a 4, you keep trying unless make another 4. If you don’t throw a 4, you keep trying unless you throw a 7.you throw a 7.

5.5. If you throw a 7 before you throw a 4 (or whatever point you are If you throw a 7 before you throw a 4 (or whatever point you are trying to make), you lose. This is called ‘craps’. If you throw a 4 trying to make), you lose. This is called ‘craps’. If you throw a 4 (or whatever other point you are trying to make), before you throw (or whatever other point you are trying to make), before you throw a 7, then you win, and you get to roll again.a 7, then you win, and you get to roll again.

Flowchart – The Game of CrapsFlowchart – The Game of Craps

Lay StakeLay Stake

Roll Dice (#1)Roll Dice (#1)

7 or 7 or 11?11?

2 or 2 or 12?12?

NONO

Roll Dice (#2)Roll Dice (#2)

NONO

7?7?

Same as Same as (#1)(#1)

NONO

Collect WinningsCollect Winnings

Pass on the diceYESYES

NONO

YESYES

YESYES

YESYES

Quality Tools - 7 Statistical MethodsQuality Tools - 7 Statistical Methods

- Used for locating & - Used for locating & focusing on concerns.focusing on concerns.

• Pareto Pareto DiagramDiagram

• Fishbone Fishbone DiagramDiagram

- Sums up the relationship - Sums up the relationship between each characteristic between each characteristic (concern) & the factors (concern) & the factors (causes).(causes).

- Allows display of many Allows display of many possible causes.possible causes.

- A brainstorming tool.A brainstorming tool.

- Used to show a general - Used to show a general view of process data.view of process data.

• HistogramHistogram

• StratificationStratification

- Summarises process Summarises process date collected over time.date collected over time.

- Organising data into Organising data into useful & meaningful lots.useful & meaningful lots.


- Stratification often Stratification often needed.needed.

• Scatter Scatter DiagramDiagram

- Used to learn the - Used to learn the relationship between 2 relationship between 2 sets of data.sets of data.

• CheckCheck SheetsSheets

• Graphs & Graphs & Control ChartsControl Charts

- Used to gather & - Used to gather & arrange data.arrange data.

- Used to arrange data Used to arrange data pictorially & make it easier pictorially & make it easier to understand.to understand.


0

5

10

15

20

25

30

PA

INT

W/L

EA

K

TR

IM

CIVIC

ACCORD

X & Y - AXIS ON GRAPHSX & Y - AXIS ON GRAPHSX -AXISX -AXIS

• Along the bottom.Along the bottom.

- - You learn to crawl You learn to crawl along the floor on all along the floor on all foursfours ‘X’. ‘X’.

Y-AXISY-AXIS• Horizontal – Up both sides.Horizontal – Up both sides.

- - When older you can stand When older you can stand up and reach for the skyup and reach for the sky ‘Y’. ‘Y’. X - AXISX - AXIS

Y

- AX

ISY

- AX

IS

PARETO DIAGRAMPARETO DIAGRAM

• Shows concerns by listing Shows concerns by listing them in order of quantity in them in order of quantity in the form of a bar.the form of a bar.

Quality %90 100%

80

70No. ofConcern 60

Items50

50%

40

30

20

10

0 0

Dirt

Pai

ntin

g

Scr

atch

Def

orm

Pla

ting

othe

r

Cum

u la t

ive

Oc c

u pa n

c y R

a te

• The % shown on the right The % shown on the right hand Y –Axis shows the hand Y –Axis shows the cumulative occupancy rate cumulative occupancy rate in the form of a Kinked in the form of a Kinked Line Graph. Line Graph.

Pareto Diagram - 3 StepsPareto Diagram - 3 Steps

1.1. Collect the dataCollect the data

2.2. Prepare a Calculation ChartPrepare a Calculation Chart

3.3. Prepare the Pareto DiagramPrepare the Pareto Diagram

ITEM Number ofConcern Items

Scratch 15

Painting 20

Plating 5

Deforms 10

Dirt 35

Other 5

TOTAL 90

Pareto Step 1 – Collect DataPareto Step 1 – Collect Data

This example shows This example shows data by item, about data by item, about

concerns in an concerns in an appearance inspection appearance inspection

of 500 cars over a period of 500 cars over a period of 1 month.of 1 month.

Collect the data in the form of a table.Collect the data in the form of a table.

ITEM Number ofConcern Items

Scratch 15

Painting 20

Plating 5

Deforms 10

Dirt 35

Other 5

TOTAL 90

Step 2 – Prepare Calculation ChartStep 2 – Prepare Calculation Chart

2. Calculate the accumulated no. of concern items.2. Calculate the accumulated no. of concern items.

1. Re-arrange in order of frequency1. Re-arrange in order of frequency

1.1. 2.2. 3.3. 4.4.

Calculation Chart Preparation – 4 StagesCalculation Chart Preparation – 4 Stages

4. Calculate the % cumulative occupancy rate4. Calculate the % cumulative occupancy rate

3. Calculate the % occupancy rate for each item.3. Calculate the % occupancy rate for each item.

ITEM Number of Accumulative No Occupancy

Cumulative %Concern Items of Concern Items Rate % Occupamcy Rate

Dirt 35 35 38.9 38.9

Painting 20 55 22.3 61.2

Scratch 15 70 16.7 77.9

Deforms

10 80 11.1 89.0

Plating 5 85 5.5 94.5

Other 5 90 5.5 100

TOTAL 90 n/a 100 n/a

Step 3 – Prepare the Pareto DiagramStep 3 – Prepare the Pareto Diagram

1. Graduate left hand Y – Axis to allow 1. Graduate left hand Y – Axis to allow

entry of all data (N=90)entry of all data (N=90)

Motel: Model A

Period: 1-30 Nov98

Prepared By:

J. Bloggs

Quality %90 100%

80

70No. ofConcern 60

Items50

50%

40

30

20

10

0 0

Dirt

Pai

ntin

g

Scr

atch

Def

orm

Pla

ting

othe

r

Cu m

ulat

ive

Occ

upan

cy R

ate

Number of items inspected: 500

N = 902. Ratio of Y to X - Axis should be 2. Ratio of Y to X - Axis should be

1 : 1 to 2 : 11 : 1 to 2 : 1

3. Enter items on X - Axis in form of a 3. Enter items on X - Axis in form of a Bar Graph Bar Graph

4. No gas between bars & “other” last.4. No gas between bars & “other” last.



Dirt 35 35 38.9 38.9

Painting 20 55 22.3 61.2

Scratch 15 70 16.7 77.9

Deforms

10 80 11.1 89.0

Plating 5 85 5.5 94.5

Other 5 90 5.5 100


4. Insert the cumulative occupancy rate in 4. Insert the cumulative occupancy rate in the form of a Kinked Line Graph.the form of a Kinked Line Graph.

Quality %90 100%

80

70No. ofConcern 60

Items50

50%

40

30

20

10

0 0

Dirt

Pai

ntin

g

Scr

atch

Def

orm

Pla

ting

othe

rMotel: Model A

Period: 1-30 Nov98

Prepared By: J. Bloggs


Cum

ulat

ive

Occ

upan

cy R

ate

N = 90

61.2%

5. To show cumulative occupancy rate (%) 5. To show cumulative occupancy rate (%)

6. Enter relevant details.6. Enter relevant details.

- Graduate 0 - 100% range on R/H Graduate 0 - 100% range on R/H Y - Axis.Y - Axis.

- Mark R/H Y – Axis opposite total Mark R/H Y – Axis opposite total quantity 90 which is on L/H Y - Axis as quantity 90 which is on L/H Y - Axis as 100%.100%.



Dirt 35 35 38.9 38.9

Painting 20 55 22.3 61.2

Scratch 15 70 16.7 77.9

Deforms

10 80 11.1 89.0

Plating 5 85 5.5 94.5

Other 5 90 5.5 100


Step 3 – ContinuedStep 3 – Continued


Quality %90 100%

80

70No. ofConcern 60

Items50

50%

40

30

20

10

0 0

Dirt

Pai

ntin

g

Scr

atch

Def

orm

Pla

ting

othe

rMotel: Model A

Period: 1-30 Nov98


Cum

ulat

ive

Occ

upan

cy R

ate

N = 90

61.2%61.2%

DETERMINE CUMULATIVE OCCUPANCY RATE %DETERMINE CUMULATIVE OCCUPANCY RATE %

ExampleExampleYou want to see what % of the You want to see what % of the total Dirt & Painting account for?total Dirt & Painting account for?

1.1. Draw a vertical line up from Draw a vertical line up from Painting block to the Kinked Painting block to the Kinked Line graph.Line graph.

2. From the point the vertical line 2. From the point the vertical line intersects the Kinked Line intersects the Kinked Line Graph draw a horizontal arrow Graph draw a horizontal arrow to the R/H Y - Axis.to the R/H Y - Axis.

3. The point the arrow intersects 3. The point the arrow intersects the R/H Y – Axis indicates the % the R/H Y – Axis indicates the % Dirt & Painting occupy, i.e. Dirt & Painting occupy, i.e. 61.2%.61.2%.

Pareto Diagram – Viewing & UsingPareto Diagram – Viewing & Using

• Repeat the Pareto following corrective action Repeat the Pareto following corrective action to check effects of any counter-measures.to check effects of any counter-measures.

• Only top 2 or 3 items have any great influence.Only top 2 or 3 items have any great influence.

To determine the areas for improvement:To determine the areas for improvement:

• Pareto Diagrams help target effort.Pareto Diagrams help target effort.

• Complete a Pareto for the top items for causesComplete a Pareto for the top items for causes

Pareto Diagrams - PrioritisingPareto Diagrams - Prioritising

• Don’t just look at the concern in relation to Don’t just look at the concern in relation to frequency of occurrence. Examine the time frequency of occurrence. Examine the time factor to correct the concern – the result may factor to correct the concern – the result may alter your priority item/s to be tackled.alter your priority item/s to be tackled.

• It is worth noting that when preparing Pareto It is worth noting that when preparing Pareto Diagrams, the concern should be viewed from Diagrams, the concern should be viewed from different aspects.different aspects.

Concern Item Quantity Unit Time to Fix Total Time to FixDirt in paint 12 10 mins 120 mins.Scratch 19 5 mions. 95 minsDeform 7 20 mins 140 minsLoose mirror 9 3 mins. 27 minsWater leak 6 45 mins. 270 mins

Pareto Diagram – Frequency Pareto Diagram – Frequency VV Time Time

Concern Item Qty Accumulative QtyScratch 19 19Dirt in paint 12 31Loose Mirror 9 40Deform 7 47Water Leak 6 53

Concern Item Time Accumulative TimeWater leak 270 mins. 270 minsDeform 140 mins 410 minsDirt in paint 120 mins 530 minsScratch 95 mins 625 minsLoose Mirror 27 mins. 652 mins

By Frequency

By Repair Time

Scratch

Dirt in P

aint

Loose Mirror

Deform

Water leak

Water leak

Deform

Dirt in P

aint

Scratch

Loose Mirror

n = 53 100%

75%

50%

25%

0%

50

0

40

10

20

30 58%

100

200

400

500

600

0

n = 652

300

25%

50%

75%

100%

0%

63%

Pareto by Frequency

Pareto by Repair Time

CharacteristicsCharacteristics Diagram Diagramalso known as:also known as:

Fish Bone, Cause & Effect or Ishikawa DiagramFish Bone, Cause & Effect or Ishikawa Diagram

Allows a quick understanding at a Allows a quick understanding at a glance by:glance by:

Characteristic

FactorFactor

Factor

FactorFactor

FactorFactor

Sm

all

Sm

all

Big

Bo

ne

Big

Bo

ne

MediumMedium

MiniatureMiniature

• Classifying Causes (Factors).Classifying Causes (Factors).

• That are considered to effect the That are considered to effect the result (Characteristic) of a result (Characteristic) of a specific kind of activity.specific kind of activity.

• The use of arrows show the The use of arrows show the relationship between the items.relationship between the items.

BackboneBackbone

Characteristic DiagramCharacteristic Diagram

A Brain Storming ToolA Brain Storming Tool

• Allows many opinions in Allows many opinions in one diagram.one diagram.

FactorFactorFactorFactor

Smal

lB

ig B

one

Medium

Miniature

CharacteristicCharacteristic

FactorFactorFactorFactor

Backbone

• Leads to a firm Leads to a firm understanding of the understanding of the cause/s of concerns & cause/s of concerns & taking appropriate actions. taking appropriate actions.

• Allows greatest number Allows greatest number of Associates to of Associates to exchange opinions.exchange opinions.

Preparing a Characteristics DiagramPreparing a Characteristics Diagram

4. Enter the necessary information.4. Enter the necessary information.

The 4 Steps:The 4 Steps:

1. Determine the Characteristics.1. Determine the Characteristics.

2. Enter the Factors.2. Enter the Factors.

3. Check the Factors.3. Check the Factors.

Shipping N + 1, RFT, Operating rate, Shipping N + 1, RFT, Operating rate, production volume.production volume.

• DeliveryDelivery

• QualityQuality

• CostCost

Dimension, performance, appearance.Dimension, performance, appearance.

Profit, loss, material/labour cost, re-work.Profit, loss, material/labour cost, re-work.

Step 1 – Typical CharacteristicsStep 1 – Typical Characteristics

• MoraleMorale Absence, lateness, benefits.Absence, lateness, benefits.

• SafetySafety Number of accidents, accident free days, typeNumber of accidents, accident free days, typeof injuries.of injuries.

• EnvironmentEnvironment Energy consumption, emissions, spillage, Energy consumption, emissions, spillage, recycling, land fill reduction. recycling, land fill reduction.

• Draw an arrow from left to Draw an arrow from left to right which serves as the right which serves as the backbone.backbone.

Characteristic

• At the tip of the arrow At the tip of the arrow enter the chosen enter the chosen Characteristic and enclose Characteristic and enclose in a box.in a box.

Step 1 – Inputting the CharacteristicsStep 1 – Inputting the Characteristics

Step 2 – Enter the FactorsStep 2 – Enter the Factors

• Enter the Factors at the end Enter the Factors at the end of the big bones which join of the big bones which join the backbone.the backbone.

CharacteristicCharacteristic

FactorFactor

FactorFactor

Big

B

ig

Bo

ne

Bo

ne • The The “4 M’s”“4 M’s” are usually are usually

entered as Factors. entered as Factors. Alternatively the process Alternatively the process names may be used.names may be used.

The 4 M’s - (Factors)The 4 M’s - (Factors)

4. Method4. Method

Characteristic

Factor Factor

FactorFactor FactorFactor

1. Material1. Material

2. Machine2. Machine

3. Man3. Man

Material Machine

Man Method

Step 3 – Check the FactorsStep 3 – Check the Factors

Characteristic

Big

Bo

ne

Factor

Medium

Smal

lMiniature

Check:Check:• Each factor starting with the Each factor starting with the medium bones.medium bones.

• Proceed to the small and miniature Proceed to the small and miniature bones until you reach items so bones until you reach items so concrete they allow actions to be concrete they allow actions to be taken.taken.

Man

Experience

Poor Quality

New Starters

Not Trained

• Encircle in or those factors Encircle in or those factors likely to effect the characteristic andlikely to effect the characteristic and where further consideration/actions where further consideration/actions are needed.are needed.

Step 4 – Enter the Necessary ItemsStep 4 – Enter the Necessary Items

• Name of Associate who prepared the Name of Associate who prepared the Characteristic Diagram.Characteristic Diagram.

Include:Include:

• PurposePurpose

• DateDate

• Time if applicable.Time if applicable.

Viewing & Using a Characteristics DiagramViewing & Using a Characteristics Diagram

• When all necessary factors are entered a large number of When all necessary factors are entered a large number of bones should result.bones should result.

• If there are only a small number of bones, then the If there are only a small number of bones, then the “ “Factors”Factors” should be checked – You may need to use should be checked – You may need to use different ones.different ones.

• In a well prepared Characteristics Diagram various In a well prepared Characteristics Diagram various factors are complexly meshed together.factors are complexly meshed together.

• Encircling key items in for example will help Encircling key items in for example will help highlight items for consideration and potential highlight items for consideration and potential improvement.improvement.

• The use of Pareto or Histograms for these items will The use of Pareto or Histograms for these items will improve effectiveness.improve effectiveness.

Hardness ofSintered Parts

Personnel

Work Method

Equipment (Jigs)

Material

Amount of Work

Knowledge

Amount ofknowledge

Usage

Degree ofunderstanding

Productionschedule

Balance

EagernessTo work

Physical condition

FatigueEnvironment

Irritation

SkillExperience

EducationType ofEducation

Measuring Method

Work Standard

Hardness meter

Type

Procedure

Contents Revision

Understanding

Parts mounting

PositionQuality

Number of stages

Charging intoincinerator

Period

Season Time

Charging order

Jigs

Structure

Muffle

DeformationShape

Tray

Material

Weight

Zone composition

Tray processingcapability

Heating

Atmosphere

Cooling

Powder

Moulding

Mixed Powder

Temperature

Temperature Speed

Time

Speed

Time

How it flows Gas Flow

Dew pointGas composition

Composition

RatioAlloy elements

Flow rate

Mixed density

Experience

WeightDensityBalance

VolumeShape

Carbon powder

SizeQuantity

Purity

Iron Powder

KindDensity

Process: Sintering FurnacePreparation Date: 12 Nov 2000Prepared by: J Smith

Characteristics Diagram - ExampleCharacteristics Diagram - Example

HistogramsHistograms

• Arranges large quantities Arranges large quantities of process data allowing of process data allowing an easy understanding of an easy understanding of the entire system.the entire system.

Histogram of Mechanical Parts Dimension (Standard: 25.35 +/- 0.06 mm.)

28 n = 100 Standard Range

26

24

22

20

18

16

14

12

10

8

6

4

2

0

25.28 25.30 25.32 25.34 25.36 25.38 25.40

25.27 25.29 25.31 25.33 25.35 25.37 25.39 25.41

Parts Dimension (mm)

Freq

uenc

y

• Allows a general view ofAllows a general view of a situation which is a situation which is difficult to understand by difficult to understand by merely looking at the data.merely looking at the data.

• Allows comparison of Allows comparison of obtained data with relevant obtained data with relevant standard.standard.

Histogram of Mechanical Parts Dimension (Standard: 25.35 +/- 0.06 mm.)

28 n = 100 Standard Range

26

24

22

20

18

16

14

12

10

8

6

4

2

0

25.28 25.30 25.32 25.34 25.36 25.38 25.40 25.42

25.27 25.29 25.31 25.33 25.35 25.37 25.39 25.41


Fre

qu

ency

• Shows actual situation.Shows actual situation.

Features Include:Features Include:

• Shows how data is Shows how data is distributed.distributed.

• Shows presence of Shows presence of scattered data.scattered data.

Histograms

Histograms - 3 StepsHistograms - 3 Steps

3.3. Prepare the Histogram.Prepare the Histogram.

1. Collect the data.1. Collect the data.

2. Prepare Frequency Distribution Table.2. Prepare Frequency Distribution Table.

Histogram - Step 1 Collect the DataHistogram - Step 1 Collect the Data

• Collect the data on a pre-prepared Data Sheet.Collect the data on a pre-prepared Data Sheet.

• The following example is prepared from the The following example is prepared from the measurements of the outer diameter of Machined measurements of the outer diameter of Machined Part ‘A’. Samples were picked up at a rate of 5 per Part ‘A’. Samples were picked up at a rate of 5 per day for a 20 day period.day for a 20 day period.

X 1 X 2 X 3 X 4 X 506-Sep 13.8 14.2 13.9 13.7 14.807-Sep 14.2 14.1 13.5 14.3 14.010-Sep 13.4 14.3 14.2 14.1 13.911-Sep 14.2 13.7 13.8 14.1 13.712-Sep 13.9 14.5 14.0 13.3 13.813-Sep 14.1 12.9 * 13.9 14.1 13.714-Sep 13.6 14.0 14.0 14.4 14.317-Sep 14.6 13.7 14.7 13.6 14.318-Sep 14.4 14.0 13.7 14.1 13.919-Sep 13.1 14.4 14.4 14.9 14.0

DateData

X 1 X 2 X 3 X 4 X 520-Sep 13.6 13.8 13.8 13.6 13.821-Sep 14.1 14.0 13.0 14.2 14.724-Sep 14.0 13.7 13.8 14.8 13.725-Sep 13.5 14.1 14.0 13.6 14.326-Sep 15.0 ^ 13.9 13.5 13.9 14.227-Sep 13.7 14.0 14.1 13.7 13.528-Sep 14.0 13.2 14.5 13.9 14.201-Oct 13.9 14.8 13.6 14.0 14.802-Oct 13.5 13.9 14.0 14.7 14.503-Oct 14.4 14.5 13.8 13.3 14.0

DateData

* = Smallest Value ^ = Largest Value

Step 2 – Prepare Frequency Distribution TableStep 2 – Prepare Frequency Distribution Table

• Enter totals in the Enter totals in the Frequency Column & Frequency Column & Total the column.Total the column.

Class No. Class Range (mm) Midrange Check Freq.

1 12.85 - 13.05 12.95 ll 22 13.05 - 13.25 13.15 ll 23 13.25 - 13.45 13.35 lll 34 13.45 - 13.65 13.55 llll llll l 115 13.65 - 13.85 13.75 llll llll llll lll 186 13.85 - 14.05 13.95 llll llll llll llll llll 247 14.05 - 14.25 14.15 llll llll llll l 168 14.25 - 14.45 14.35 llll llll 109 14.45 - 14.65 14.55 llll 510 14.65 - 14.85 14.75 llll ll 711 14.85 - 15.05 14.95 ll 2

Total 100

Frequency Distribution TableFrequency Distribution Table

• Decide how many Decide how many classesclasses

• Enter midranges for Enter midranges for each class.each class.

• Count & mark off in Count & mark off in the Check Column.the Check Column.

Total should = “n”

and class ranges and class ranges to divide data into & enter.to divide data into & enter.

Step 3 – Prepare the HistogramStep 3 – Prepare the Histogram

• Enter the details, Enter the details, including standard including standard range.range.

26 Standard 14.0 +/- 1.5

24

22 Part No. : 11000-384-0000Part Name: Part A

20 Measuring point: HoleMeasuring Period:

18 6 Sep98 - 3Oct99 Prep Date: 6Oct98

16 Prep by: J . Bloggs

14

12

10

8

6

4

2

12.55 12.95 13.35 13.75 14.15 14.55 14.95 15.3512.75 13.15 13.55 13.95 14.35 14.75 15.15

Fre

qu

en

c

y

Histogram of Part A Outer Diameter

n = 100

• Graduate the X-Axis Graduate the X-Axis & enter the class & enter the class values (Midrange).values (Midrange).

• Graduate the Y-Axis Graduate the Y-Axis with the frequencywith the frequency

• Draw the Bar Graph. Draw the Bar Graph. There should be no There should be no gaps.gaps.


Viewing & Using a HistogramViewing & Using a Histogram

• Rough guide of kind of abnormality.Rough guide of kind of abnormality.

Various Shapes of Histograms

Stable Process Precipice Type

Missed Tooth Type Isolated Island Type

Observe the shape to locate abnormality:Observe the shape to locate abnormality:

• Neat shape = Stable process.Neat shape = Stable process.

• Irregular shape = Abnormality.Irregular shape = Abnormality.

When data satisfies standard In the case of a large discrepancy

In the case of eccentricity In the case of eccentricity & large discrepancy

Entry of standard values shows/allows:Entry of standard values shows/allows:

• Conformity to relevant standards.Conformity to relevant standards.

• Degree of acceptability/unacceptability. Degree of acceptability/unacceptability.

• Ability to locate areas for improvement.Ability to locate areas for improvement.

Viewing & Using a HistogramViewing & Using a Histogram

StratificationStratification

• Therefore data should be classified prior to Therefore data should be classified prior to gathering based on the 4 M’s or QCDMES.gathering based on the 4 M’s or QCDMES.

• Stratification is gathering & observing large Stratification is gathering & observing large quantities of data that may allow some kind of quantities of data that may allow some kind of information to be obtained.information to be obtained.

• If various factors are mixed together, proper If various factors are mixed together, proper measures & judgements can not be taken.measures & judgements can not be taken.

Examples of Stratification based on the 4M’sExamples of Stratification based on the 4M’s

• Classified by fabricating machine, jig, Classified by fabricating machine, jig, tool and new or old machine device.tool and new or old machine device.

MachineryMachinery&&

EquipmentEquipment

AssociateAssociate • Each Associate, Team of Associate Each Associate, Team of Associate doing the same kind of work, etc. doing the same kind of work, etc. classified by age or number of years classified by age or number of years experience.experience.

Raw MaterialRaw Material • Classified by supplier, trademark, lot, Classified by supplier, trademark, lot, receiver, time of purchase & storage receiver, time of purchase & storage period or method.period or method.

Work MethodWork Method • Classified by work method, measuring Classified by work method, measuring method & working conditions.method & working conditions.

Stratification ExamplesStratification Examples

ABCDEFGHI

As

so

cia

te

Number of Days Absent

Days Absent by Associate

HISTOGRAM - OUTER DIAMETER OF PART A - MACHINE A

302520151050

HISTOGRAM - OUTER DIAMETER OF PART A - MACHINE B

302520151050

Standard Range

Standard Range

HISTOGRAM - OUTER DIAMETER OF PART A - MACHINE A & B

60

50

40

30

20

10

0

Standard Range

Stratification into Machine A & B

Scatter DiagramScatter Diagram

• Scatter Diagrams Scatter Diagrams

represent two types of data represent two types of data related to each other, related to each other, e.g. e.g. human height & weight.human height & weight.

SCATTER DAIGRAM CONCERNING

65 QUENCHING TEMPERATURE & HARDNESS

60

55

50

45

0

C800

850 900Quenching

Ha

rdn

es

s

Period: 12Oct98 - 10Nov98Process: Quenching Machine APrep. Date: 13 Nov98Prepared by: A.N. Other

HRC • Pareto & Histograms arePareto & Histograms are used to obtainused to obtain information using one information using one type of data.type of data.

Scatter Diagrams - The 4 StepsScatter Diagrams - The 4 Steps

4. Enter the relevant details.4. Enter the relevant details.

1. Gather the corresponding data.1. Gather the corresponding data.

2.2. Prepare the graph.Prepare the graph.

3. Plot the data on the graph.3. Plot the data on the graph.

Step 1 – Gather the Corresponding DataStep 1 – Gather the Corresponding Data

• Minimum of 30 lots of data required.Minimum of 30 lots of data required.

Quenching Hardness Quenching Hardness

No. Temp. ( 0C ) (HRC) No. Temp. ( 0C ) (HRC)

1 850 50 17 910 552 870 52 18 810 473 860 50 19 810 444 840 49 20 900 575 850 51 21 860 516 880 55 22 830 467 830 47 23 850 468 840 46 24 880 549 870 51 25 910 5710 830 50 26 860 4911 840 48 27 860 5012 870 51 28 880 4813 890 57 29 870 5514 870 53 30 910 5915 850 48 31 890 5516 820 44 32 900 56

Steps 2/3/4Steps 2/3/4Prepare, Plot Graph & Enter DetailsPrepare, Plot Graph & Enter Details

3. Values increase as you go 3. Values increase as you go across the X-Axisacross the X-Axis

SCATTER DAIGRAM CONCERNING

65 QUENCHING TEMPERATURE & HARDNESS

60

55

50

45

0

C80 85 90

Quenching Temperature

Ha

rdn

es

s

Period: 12Oct98 - 10Nov98Process: Quenching Machine APrep. Date: 13 Nov98Prepared by: A.N. Other

HRC1. Enter causes (Factors) on1. Enter causes (Factors) on X-AxisX-Axis

2. X & Y-Axis should be almost2. X & Y-Axis should be almost almost equal in length.almost equal in length.

and results and results (Characteristics) on Y-Axis.(Characteristics) on Y-Axis.

& up Y-Axis.& up Y-Axis.

Scatter Diagram – Viewing & UsingScatter Diagram – Viewing & Using

• Positive correlation - Y increases with X.Positive correlation - Y increases with X.

Positive Correlation Positive Correlation Likely No Correlation

Negative Correlation Negative Correlation Likely Correlation may be Found if Stratification is carried out

• Negative correlation - Y decreases as X increases. Negative correlation - Y decreases as X increases.

Check SheetsCheck Sheets

• Allows a general view of data.Allows a general view of data.

Model: XY123 Engine Concern Check SheetDay/Month

Defect

TP Re-adjust. l l ll l ll l

Goveror Re-adjust. llll llll lll llll llll lll lll ll ll llll

Bolt Re-tighten l I I I

Other I II I I II I III I II I

Total 7 7 6 8 7 5 6 5 6 6

T/Ldr. Signature X

Co-Ord Signature X

07-Oct 15-Oct 16-Oct08-Oct 09-Oct 10-Oct 11-Oct 12-Oct 13-Oct 14-Oct

• Prepared in advance.Prepared in advance.

• Used to gather & arrange collected data.Used to gather & arrange collected data.

• No fixed format – Designed to suit each case.No fixed format – Designed to suit each case.

GraphsGraphs

• Graphs help in decision making & in taking appropriate Graphs help in decision making & in taking appropriate actions.actions.

Advantages of using graphs:Advantages of using graphs:

• It is extremely difficult to observe numeric It is extremely difficult to observe numeric changes when data is merely gathered & entered changes when data is merely gathered & entered on paper. Graphs present a visual picture which on paper. Graphs present a visual picture which is easier to understand.is easier to understand.

• Graphs break down language barriers.Graphs break down language barriers.

Commonly Used GraphsCommonly Used Graphs

• Strip GraphsStrip Graphs

• Bar GraphsBar Graphs

• Kinked-Line GraphsKinked-Line Graphs

• Circle GraphsCircle Graphs

Bar GraphsBar Graphs• Bar Graphs compare two or more quantities Bar Graphs compare two or more quantities represented by the length of the bars.represented by the length of the bars.

240

180

160

140

120

100

80

Prepared by: A. Other

Prep. Date: 6J an99

£.K

Sales

Sales Classified by Branch

1998 Total Sales: £1,020.000

0

20

40

60

80

100

120

140

160

180

200

220

240

Unit -Write outside

Y-Axis Description

Number the scale

Enter Zero

Title is generally located

under the graphName bar items on X-Axis

Datum Line - Always set at zero

Enter date of preparation

& name of person who

prepared graph

Bar Totals - Optional

Write date of data & other related information in

middle of lower part of graph Gap between bars should be

half or equal to bar width

Kinked-Line GraphKinked-Line Graph• Used to show quantity changes over time.Used to show quantity changes over time.

Prepared by: J. BloggsPrep Date: 7Jul98

SECTION A - MONTHLY ABSENCE RATE (%)

0

0.5

1.0

1.5

2.0

(%)

JAN 98 FEB 98 MAR 98 APR 98 MAY 98 JUN 98

AB

SE

NC

E R

AT

EEnter the Unit

Description of Y-Axis

Number the Scale

DatumLine Title

Dots

Enter date of preparation

& name of person who

prepared graph

X-Axis Values

Circle GraphCircle GraphDatum Line

Starts at 12 o’clock Clockwise from 12 o’clock.Largest to smallest

Date prepared &Name of person

Who prepared the graph

80Ki80Kin = 42n = 42

Efficiency30%

Cost25%

Quality15%

Safety14%

Equipment13%

Other3%


Prep Date: 10 Oct 03

Subject – Contents of NH Circle ActivitiesSubject – Contents of NH Circle Activities Title

Total quantity of data

Segment ratio

Period covered

Other is always last

Strip GraphStrip Graph• A Strip Graph is a horizontal rectangle divided into A Strip Graph is a horizontal rectangle divided into segments in accordance with the ratio of each item.segments in accordance with the ratio of each item.

Total Exports: 2,541,000 units

1985 TWO-WHEEL EXPORTS FROM JAPAN BY REGION

0 10 20 30 40 6050 80 9070 100

Southeast Asia36.9%

North America31.5%

Europe16.4%

MiddleEast7.0%

Oce

ania

3.3

%

%

Prepared by: J.BloggsPrep. Date: 10Jan86

Af r

i ca

2.5%

Cen

t ral

& S

out h

Am

eric

a 2.

4%

Enter ZeroScale numbers on top

Graduation marks inside

Unit at top

Name the segments% Values optional

Title is usually locatedunder graph

Date prepared &

Name of person who

prepared graph

Control ChartsControl Charts

• A Control Charts consists of graphs with data A Control Charts consists of graphs with data movements shown as dots and kinked lines, movements shown as dots and kinked lines, containing statistical ideas (i.e. control limit containing statistical ideas (i.e. control limit lines).lines).

• The location and way the dots are arranged in The location and way the dots are arranged in the Control Chart allows confirmation as to the Control Chart allows confirmation as to whether the process status (i.e. control whether the process status (i.e. control status) is normal.status) is normal.

• The X-R Control Chart is an example of such a The X-R Control Chart is an example of such a chart.chart.

• It is used to control the mean and range of a process.It is used to control the mean and range of a process.

X - R Control ChartX - R Control Chart

• The X - R Control Chart is often used in HUM’s The X - R Control Chart is often used in HUM’s production processes.production processes.

• The method of preparing & using an X – R Control Chart is The method of preparing & using an X – R Control Chart is fully explained in Course ‘F’ Text & also the process fully explained in Course ‘F’ Text & also the process analysis training package which is available in HUM’s analysis training package which is available in HUM’s Open Learning Centre.Open Learning Centre.

X = X Total / Sample Set Number = / =

R = R Total / Sample Set Number

= /

=

X Control Chart

U.C.L. = X + A2 R =

X =

L.C.L. = X - A2 R = = X

=

R Control Chart

U.C.L = D4R = X

=

LCL=D3RIGNORE IF SAMPLE No. IS SMALLER THAN 6

TL CORD. MGR.

Control Limit Calculation Coefficient

n2345

A2 D4

1.8801.02307290.577

3.2682.5742.2822.115

S0901-D-004 23-Dec-98

PROCESS CONTROL CHART (X - R )

COMMENTS

Instruction*1. X & R values (Kinked line) Black Solid Line2. UCL & LCL shall be made by (dash-dot)3. Centre line shall be made by (solid line)

*Completion instructions on the reverse

Measured period (MM / YY)

........................................./......................

1S2S

NO.LOT

X1

X2

X3

X4

X5

TOTALAVERAGE X

RANGE R

DATE MEASURED

ME

AS

UR

ED

VA

LU

E

PART NAME STANDARD SAMPLING FREQUENCY MEASUREMENT TOOL TIGHTENING TOOL

R C

ON

TR

OL

CH

AR

TX

CO

NT

RO

L C

HA

RT

0

GROUP NO. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

HIGHEST-LOWEST

SUMNo. OF READINGS

SIZE

7 - quality tools

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