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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’.
Quality Tools - Deming Control CircleQuality Tools - Deming Control Circle
• PlanPlan
• DoDo
• CheckCheck
• ActionAction
PP
DD
AA
CC
Aim is continuous improvementAim is continuous improvement
Quality Tools - Deming Control CircleQuality Tools - Deming Control Circle
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.
Quality Tools - 7 Statistical MethodsQuality Tools - 7 Statistical Methods
- 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.
Quality Tools - 7 Statistical MethodsQuality Tools - 7 Statistical Methods
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.
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
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
Number of items inspected: 500
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%.
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 – ContinuedStep 3 – Continued
Number of items inspected: 500
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%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
Parts Dimension (mm)
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.
Parts Dimension (mm)
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%
Prepared By: J. Bloggs
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
Recommended