基本七(B7) 质量工具(1)

1、The Basic Seven (B7) Tools of QualityA PowerPoint Training PresentationBy Keith H. CooperAs much as 95% of quality related problems in the factory can be solved with seven fundamental quantitative tools. - Kaoru Ishikawa 1What are the Basic Seven Tools of Quality?Fishbone DiagramsHistogramsPareto An

2、alysisFlowchartsScatter PlotsRun ChartsControl Charts2Where did the Basic Seven come from?Kaoru IshikawaKnown for “Democratizing Statistics”The Basic Seven Tools made statistical analysis less complicated for the average personGood Visual Aids make statistical and quality control more comprehendible

3、.3The Basic Seven (B7) Tools of QualityFishbone DiagramsNo statistics involvedMaps out a process/problemMakes improvement easierLooks like a “Fish Skeleton”4Constructing a Fishbone DiagramStep 1 - Identify the ProblemStep 2 - Draw “spine” and “bones”Example: High Inventory Shrinkage at local Drug St

4、oreShrinkage5Constructing a Fishbone DiagramStep 3 - Identify different areas where problems may arise fromEx. : High Inventory Shrinkage at local Drug StoreShrinkageemployeesshoplifters6Constructing a Fishbone DiagramStep 4 - Identify what these specific causes could beEx. : High Inventory Shrinkag

5、e at local Drug StoreShrinkageshopliftersAnti-theft tags poorly designedExpensive merchandise out in the openNo security/ surveillance7Constructing a Fishbone DiagramEx. : High Inventory Shrinkage at local Drug StoreShrinkageshopliftersAnti-theft tags poorly designedExpensive merchandise out in the

6、openNo security/ surveillanceemployeesattitudenew traineetrainingbenefitspractices8Constructing a Fishbone DiagramStep 5 Use the finished diagram to brainstorm solutions to the main problems.9The Basic Seven (B7) Tools of QualityHistogramsBar chartUsed to graphically represent groups of data10Constr

7、ucting a HistogramFrom a set of data computesummean (x)MaxMinRange (max-min)11Constructing a HistogramUse range to estimate beginning and end Calculate the width of each column by dividing the range by the number of columnsRange# of Columns= Width12Acme Pizza ExampleLets say the owner wants a distri

8、bution of Acmes Thursday Night SalesData 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

9、2 1 2 1 2 2 2 4 2 413Acme Pizza ExampleMean = 2.032258 Max = 7 Min = 0 Range = 7 QuestionFor 7 columns what would the width be?Range/Columns=7/7=1 slice14Acme Pizza ExampleSlices of Pizza# times orderedHistogram15Constructing a HistogramHow is this helpful to Acme?2 slices of pizza most common order

10、 placedDistribution of sales useful for forecasting next Thursdays late night demandIf you were an Acme manager how could you apply this information?16The Basic Seven (B7) Tools of QualityPareto AnalysisVery similar to HistogramsUse of the 80/20 ruleUse of percentages to show importance17Acme Pizza

11、(part 2)SlicesFrequency% 01.31 33 13.092 65 25.7938 3.174 12 4.7650060071 .318Acme Pizza (part 2)The completed Pareto Analysis results in the following graph:Slices of Pizza# times ordered214375619Acme Pizza (part 2)Critical ThinkingHow does the Pareto Analysis differ from the Histogram?How can this

12、 be a useful tool to the Acme boss?20The Basic Seven (B7) Tools of QualityFlowchartsA graphical picture of a PROCESSProcessDecisionThe process flow21FlowchartsDont Forget to:Define symbols before beginningStay consistentCheck that process is accurate22Acme Pizza Example (Flowchart) WindowTake Custom

13、er Money? (start) OrderGet PizzaLockupPut More in Oven 2 Pies Available? Time to close? Take to Customernoyesnoyesnoyes23How can we use the flowchart to analyze improvement ideas from the Histogram? WindowTake Customer Money? (start) OrderGet PizzaLockupPut More in Oven 2 Pies Available? Time to clo

14、se? Take to Customernoyesnoyesnoyes24Want some practice?Make a flowchart for:Taking a showerCooking dinnerDriving a carHaving a partyCreating a FlowchartAny other processes you can think of?25The Basic Seven (B7) Tools of QualityScatter Plots2 Dimensional X/Y plotsUsed to show relationship between i

15、ndependent(x) and dependent(y) variables26Acme Pizza (Scatter Diagram)Minutes Cooking Defective Pies10145830575 2060 14204256In this simple example, you can find the existing relationship without much difficulty but27Scatter DiagramsEasier to see direct relationshipTime Cooking (minutes)Defective Pi

16、zzas28Scatter DiagramsAs a quality toolWhat does this tell Acme management about their processes?Improvements?Time Cooking (minutes)Defective Pizzas29The Basic Seven (B7) Tools of QualityRun chartsTime-based (x-axis)CyclicalLook for patterns30Run Charts8 9 10 11 12 1 2 3 48 9 10 11 12 1 2 3 48 9 10

17、11 12 1 2 3 4PM- AMPM- AMPM- AMThursdayWeek 1ThursdayWeek 2ThursdayWeek 35 10 15 20 25 30 35 40 45 50 55 60 65 70 75 80 85 90 95 100Slices/hourTime31The Basic Seven (B7) Tools of QualityControl ChartsDeviation from MeanUpper and Lower SpecsRange32Control ChartsUpper LimitLower LimitUnacceptable devi

18、ationX33Control ChartsAcme Pizza Management wants to get in on the control chart actionAverage Diameter = 16 inchesUpper Limit = 17 inchesLower Limit = 15 inches34Acme example Control ChartsUpper Limit17 inchesLower Limit15 InchesSmall PieX16 inches=35Acme example #50Control ChartsPies within specifications were acceptableOne abnormally small pie is “uncommon”Should be examined for quality control36SummaryBasic Seven Tools of QualityMeasuring dataQuality Analysis“Democratized statistics”37BibliographyFoster, Thomas. Managing Quality