5Why培训资料英文版

1、July 20111Nexteer 5 Why Analysis5 Why Effective Root Cause AnalysisJuly 20112nWhen to Use 5 Whyn5 Why Process and Examplesn5 Why Exercise nResources and Referencesn5 Why and Customer Problem Solving FormatsAgendaJuly 20113Problem Solving QuizWho are the best people at asking questions to solve a pro

2、blem?July 20114Problem Solving QuizWhy?Why?Why?Why?Why?Children!Why?.because they keep asking objective, open-ended questions until the answer is simple and clearThis is the theory behind the 5 Why!July 20115When to Use 5 WhynCustomer Issues-Required for all WFCCs (Worldwide Formal Customer Complain

3、t)-Used for informal complaints including Field Engineer Incident reports-Used for warranty issuesnSupplier Issues-Must used by suppliers for all problem reports nInternal Issues (optional)-Quality System Audit Non-conformances-First Time QualityJuly 20116n5 Why is a problem solving tool-Find root c

4、ause by analyzing cause and effect relationshipsnCan be used with various problem solving formats-Nexteer Problem Solving-GM Drill Deep-Ford 8 D (Discipline)-Chrysler 8 StepWhen to Use 5 Why5 Why, when combined with other problem solving methods, is a very effective toolJuly 20117Nexteer 5 Why Forma

5、tJuly 201185 Why AnalysisnGeneral Guidelines-Cross-functional team must be used to problem solveInclude Operators, Engineers, Quality, PC&L, etcNeed knowledge, opinions, and observations of different peopleFord D1 Establish the TeamnFord recommendation is 4-10 team members-Dont jump to conclusio

6、ns or assume the answer is obviousSame issue may be due to a different causePrevious corrective actions may have corrected only a symptom-Include pictures (photos, graphics)Keeps team focused on issueHelps customer/others understand corrective action and apply lessons learnedJuly 20119Problem Defini

7、tionnDefine the problem-Problem statement clear and accurate -Define problem as the customer sees it-Include where and how problem was found, and how many pieces -Do not add “causes” into the problem statementnAre these examples good?-Customer received part with a broken mounting pad due to improper

8、 machining-Noisy pump-Customer assembly plant detected noise coming from halfshaft during audit-Loss of power assist-Customer states steering column binds when telescoping in low positionJuly 201110Problem DefinitionnProblem Definition = Ford D2 Describe Problem-Problem statement object and defect -

9、Problem description the is/is not analysis: what, where, when, how big-Subdivide the problem deal with one problem statement at a time-Observations vs. conclusions be aware of what side you are working from July 2011115 Why AnalysisnGeneral Guidelines-Ask “Why” until the root cause is uncovered May

10、be more than 5 Whys or less than 5 Whys-Root cause can be turned “on” and “off” with corrective actionWill addressing/correcting the “cause” prevent recurrence? If not what is the next level of cause?-If you dont ask enough “Whys”, you may end up correcting a “symptom” and not “root cause” -Correcti

11、ve action for a symptom is not effective in eliminating the cause-Analysis walking from the cause back to the problem should make sense when read in reverse using “therefore”July 201112Cookies taste really badProblemUsed goose eggs rather than chicken eggsRecipe did not specify bird typeRoot CauseIn

12、gredients are wrongCookies are undercookedWhy?Therefore5-Why ExampleJuly 201113Root Causen5 Why method uses cause and effect questions to find root causenCause and effect relationship can be infinite-All symptoms or issues can be both a cause and an effect-Stop only when you can attribute cause to a

13、 higher powernTo enable effective corrective action, stop at a point within “span of control” that will lead to greatest returnJuly 201114nThomas Jefferson Memorial Example-The National Park Service noticed the Thomas Jefferson Memorial in Washington, D.C., was deteriorating faster than other monume

14、nts. Park service rangers investigated the problem using 5 Why and formed the following chain of causes.Why does the memorial deteriorate faster? Because it gets washed more frequently?Why is it washed more frequently? Because it receives more bird droppings.Why are there more bird droppings? Becaus

15、e more birds are attracted to the monument.Root Cause ExampleJuly 201115nThomas Jefferson Memorial ExampleWhy are more birds attracted to the monument? Because there are more fat spiders in and around the monument.Why are there more spiders in and around the monument? Because there are more tiny ins

16、ects flying in and around the monument during evening hours.Why more insects? Because the monument illumination attracts more insects.-The causes could be expanded. They could try to determine why illumination attracts insects. But could a solution to that be within their control? Probably not.5 Why

17、 AnalysisJuly 201116nThomas Jefferson Memorial Example-So why couldnt they stop and consider one of the previous causes as the root cause and address with corrective action?Bird droppings coat monument with water resistant substance to allow frequent washSpiders use pesticides to remove or experimen

18、t with different lighting that is less attractive to insects-So why not consider these? Would these be the most feasible? Probably not.5 Why AnalysisJuly 201117nThomas Jefferson Memorial Example-Park service rangers decided to address the monument illumination as root cause Monument illumination att

19、racts more insects-Corrective action Turn on lighting one hour later in the evening-Measure of effectiveness Bird dropping problem reduced by 90%!5 Why AnalysisJuly 2011183 Legs of 5 WhynNexteer 5 Why includes 3 legs or questions that should be addressednSpecific Problem why did the specific problem

20、 happen? nDetection why did Nexteer not detect the specific problem? nSystemic Problem what was the system breakdown that allowed the specific problem to occur?July 201119Specific ProblemnSpecific Problem -Why did we have the specific non-conformance?-How was the non-conformance created?-Root cause

21、is typically related to operations or dimensional issuesTooling wear/breakingSet-up incorrectProcessing parameters incorrect-Typically traceable to/or controllable by the people doing the workJuly 201120Specific ProblemnSpecific Problem -Specific problem cause is typically traceable to/or controllab

22、le by the people doing the work-There may be more than one causePossibly combination or interaction of causesCan address on one form or separate 5 WhysJuly 201121Specific ProblemnSpecific Problem -Root Cause ExamplesParts damaged by shipping dropped or stacked incorrectlyOperator error poorly traine

23、d or did not use proper toolsChangeover occurred wrong parts usedOperator error performed job in wrong sequenceProcessing parameters changedExcessive tool wear/breakageMachine fault machine stopped mid-cycleJuly 201122Specific ProblemOperator did not follow instructionsDo we stop here?What if root c

24、ause is?July 201123Specific ProblemOperator did not follow instructionsDo standard work instructions exist?Is the operator trained?Were work instructions correctly followed?Are work instructions effective?Or do we attempt to find the root cause?Create a standard instructionTrain operatorCreate a sys

25、tem to assure conformity to instructionsModify instructions & check effectivenessDo you have the right person for this job/task?July 201124Specific Problem ExamplesnCustomer states steering column binds when telescoping in low position warranty-Why Excess weld wire was attached to the bracket we

26、ld reducing the clearance between the rake bracket and the jacket-Why? The torch was out of position in the jacket welder-Why? The robot drifted over time-Why? Operator interaction with the robot (i.e. Changing of nozzlesJuly 201125Specific Problem ExamplesnPower steering pump with loss of assist at

27、 assembly plant-Why? Driveshaft retaining clip had popped off sub-assembly along with scouring marks on the rotating group-Why? Driveshaft roundness out of specification-Why? Driveshaft had backed up into grinder-Why? Grind line back-up flow diverter was not workingJuly 201126Specific Problem Exampl

28、esnOperator at customer plant detected noise coming from halfshaft assembly during audit-Why? Minor diameter of the female housing was machined oversized-Why? Bore drill was cutting off center at an angle-Why? Tool block holder was bent-Why? Tool block holder was bent after a machine wreck and smash

29、-upJuly 201127Specific ProblemnSpecific Problem = Ford D4 Verify Root Cause-Other suggested tools for root causeFishbone AnalysisIs/Is Not AnalysisDOE Design of ExperimentsCause and Effect Diagram-Use Flow Diagram, PFMEA, Control Plan to review possible causesJuly 201128DetectionnDetection: -Why did

30、 the problem reach the customer? -Why did we not detect the problem?As noted by the customer orSpecific non-conformance-How did the controls fail?-Root Cause typically related to the inspection systemError-proofing not effectiveNo inspection/quality gateMeasurement system issuesJuly 201129Detectionn

31、Detection-Example Root CausesNo detection process in place cannot be detected in our plantDefect occurs during shipping Detection method failed sample size and frequency inadequateError proofing not working or bypassedGage not calibratedJuly 201130Detection ExamplesnCustomer states steering column b

32、inds when telescoping in low position warranty-Why? Excess weld wire was attached to the bracket weld reducing the clearance between the rake bracket and the jacket-Why? Operators did not identify the weld as defective-Why? Boundary samples of defective parts not available for the operator during tr

33、ainingJuly 201131Detection ExamplesnPower steering pump with loss of assist at assembly plant-Why? Driveshaft retaining clip had popped off sub-assembly along with scouring marks on the rotating group-Why? Driveshaft roundness out of specification-Why? Driveshaft roundness not checked 100%July 20113

34、2Detection ExamplesnOperator at customer plant detected noise coming from halfshaft assembly during audit-Why? Operator did not check fist part after a tool change-Why? Operator failed to follow their standardized work instructions for tool changesJuly 201133DetectionnDetection = Ford D4 Define and

35、Verify Escape Point-Escape point - place in process closest to the point where the problem is generated where the effect of the root cause should have been detected and contained but was notJuly 201134SystemicnSystemic -What was the breakdown or weakness in the process that allowed cause of specific

36、 non-conformance to occur?-Why did the possibility exist for this to happen?-Root Cause typically related to quality planning issues or quality system failuresRework/repair not considered in process designLack of effective Preventive Maintenance systemFailure mode was not considered during process p

37、lanning-Typically traceable to, or controllable by, support peopleManagement, Quality, Engineering, etc.July 201135Systemic Issue nSystemic-The root cause of the specific problem is typically a good place to start the systemic root cause analysis-Root Cause ExamplesFailure mode not on PFMEA believed

38、 failure mode had zero potential for occurrenceNew process not properly evaluated Process changed creating a new failure causeJuly 201136Systemic Issue ExamplesnSystemic Issue examples from specific causes-Parts damaged by shipping Part handling requirements not communicated-Changeover occurred Wron

39、g part usedPart storage not appropriate not clearly marked or not segregated-Processing parameters changedRequirements not documented-Excessive tool wear/breakageChanged tooling supplier or materialTool change frequency not defined-Machine fault stopped mid-cycleRecovery after machine stop not defin

40、edJuly 201137Systemic Issue ExamplesnCustomer states steering column binds when telescoping in low position warranty-Why? Operators did not identify the weld as defective-Why? Excess weld wire not identified as a failure mode on the PFMEA and control plan-Why? Excess weld wire in other program appli

41、cations is acceptableJuly 201138Systemic Issue ExamplesnPower steering pump with loss of assist at assembly plant-Why? Driveshaft out of specification-Why? Grind line back-up flow diverter was not working properly-Why? No verification method defined to ensure proper operation of flow diverterJuly 20

42、1139Systemic Issue ExamplesnOperator at customer plant detected noise coming from halfshaft assembly during audit-Why? Minor diameter of the female housing was machined oversized-Why? Operator did not take adequate steps to ensure part quality after re-tooling the machine -Why? Current work instruct

43、ions did not include proper steps to be taken after a machine wreck/smash-upJuly 201140Systemic IssuenSystemic Issue = Ford D7 Prevent Recurrence-Determine systemic cause-Modify necessary systems, policies, practices, procedures to prevent recurrence-Update FMEA, Control Plan, Process Sheets, etc-Co

44、mmon error prevention action is only an auditPREVENTION ACTIONS MUST BE PERMANENT!July 201141Corrective ActionsnCorrective Actions-Corrective action identified for each root cause-Corrective actions must be feasible, within span of control -Include owner/person responsible and timing-Consider and in

45、clude documentation updates and training as appropriate-Note: Customer approval may be required for implementation of corrective action if it results in a process changeJuly 201142Corrective ActionsnCorrective Actions = Ford D6 Implement and Validate Permanent Corrective Actions-Focus on prevention

46、actions (vs detection)-Is PPAP required?-Validate that the actions are effective and monitor long-term resultsReference Nexteer Procedure G1738 Corrective and Preventive ActionsnVerify implementation of corrective action andnVerify effectiveness of corrective action nGate Charts are required to veri

47、fy effectivenessJuly 201143Lessons LearnednLessons Learned-Nexteer has a “Look Across” process in placeEnsure lessons learned are shared across all Nexteer plants Incorporate lessons learned into common BOP (Bill Of Process) and BOD (Bill of Design) -What information should be shared with other plan

48、ts, products, or processes?-Consider similar/same products, processes, and equipment-State lessons learned in a manner that would make sense to someone not familiar with the specific cause or issue-Lessons Learned = Ford D7 Prevent Recurrence Document Lessons LearnedJuly 201144Lessons Learnedn Lesso

49、ns Learned examples:-Welding operations boundary samples of what is acceptable and what is not are needed-Operation of critical machine controls (i.e. diverters) must be verified at an appropriate frequency-Operator work instructions must include steps to be taken after machine wreck/smash-upJuly 20

50、11455 Why Analysis ExamplesGroup Exercise Review a 5 Why using what you have learned -Note: These are actual responses as sent to our Customers!-Has probable root cause been determined for:Specific issueLack of detectionSystemic issue-If not, what questions would you ask?-Do corrective actions addre

51、ss root cause?-Have Lessons Learned been noted? Can another plant learn from this?-If any above answers are “no”, what recommendations would you make to the team working on the 5 Why?July 2011465 Why Resources & ReferencesnProcedure G1738 Corrective and Preventive Action-Describes the Nexteer Pr

52、oblem Solving Process requirements-Guidelines for when to use 5 Why Analysis-Includes 5 Why Critique Sheet Appendix B-5 Why Training material -Flow diagram of Look Across processnNexteer Business System Manual-Section 5 Problem SolvingnNexteer Quality web page-Look Across Process-5 Why Examples (in

53、Look Across Process)July 2011475 Why Resources & ReferencesnGlobal Supply Management Supplier Quality-Training Material for 5 Why Analysis-Problem Reporting trainingnCustomer sites-Chrysler Covisint Portal-Ford Covisint Portal-General Motors Covisint PowernNexteer Quality Webpage-Customer Requirements-Ford Global 8D Reference GuideJuly 201148Ford 8D & 5 WhynFord Global 8D Problem