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2000,QualityToolB,LLC,all rights reservedA Strategy for Performance Excellence1 2000,QualityToolB,LLC,all rights reservedExecutive OverviewParticipant manualTools WorkbookKnowledge BreakthroughLecture notesLecture notesPerformance Excellence SeriesTraining Module Elements2 2000,QualityToolB,LLC,all rights reservedTable of ContentsPoka-Yoke(Mistake Proofing)Session 1.0Introduction.3Session 2.0Zero Defects&Costs.7Session 3.0Waste Management.12Session 4.0Zero Defect Quality(ZDQ).19Session 5.0Understanding Process Errors.27Session 6.0Four Elements of ZDQ.35Session 7.0Seven Steps to Poka-Yoke.42Session 8.0Poka-Yoke Methods.44Session 9.0Summary.673 2000,QualityToolB,LLC,all rights reservednIntroductionnDefects&CostsnWaste ManagementnZero Defect Quality(ZDQ)nUnderstanding Process ErrorsnFour Elements of ZDQnSeven Steps To Poka-Yoke AttainmentnPoka-Yoke MethodsnSummary4 2000,QualityToolB,LLC,all rights reservedWhy is“Zero Defects”an Important Concept?Key Element in our capability to implement Kaizen-Lean Manufacturing Systems.No need for“just in case”inventoriesAllows company to make only what the customer needs.5 2000,QualityToolB,LLC,all rights reservedWhy KaizenTimeCPI ProjectTimeCPITimeSavingsSavingsSavingsProcess Improvement Project ImplementedMaintenance of Process PerformanceKaizen6 Sigma Data Driven Methodology to Magnify Impact of Process Improvement Apply Control Techniques to Eliminate Erosion of Improvements Proceduralize/Standardize Improvements for Improved Maintenance of Critical Process ParametersKaizen Use Small Teams to Optimize Process Performance by Implementing Incremental Change Apply Intellectual Capital of Team Members Intimate with Process CPI Projects Emphasize Control and Long Term MaintenanceKaizen Projects Emphasize Incremental Improvements6 2000,QualityToolB,LLC,all rights reservedMajorCPITools(6s s)Kaizen LeanDescriptionCp/Cpk 44Process capability assessmentDOE 44Design of experimentsSPC 44Process control based on statistics and data analysisFMEA 44Risk assessment toolRegression 44Correlate effect one variable has on anotherProcess Map 44 44 44Map process steps to communicate and identify opportunities5 whys/2 hows 4 4 4 4 4 4 Determination methods for root cause discoveryPareto 44 44 44Column chart ranking items highest to lowestFishbone 44 4 4 44Cause/Effect Diagram5S 44 44Elimination wasteVisual Mgmt 44 4 4 44Emphasis on visual techniques to manage processPoka-Yoke 4 4 44Error proofing techniquesSpaghetti Chart 44 44Kanban 4 4 44Material storage technique used to control processTakt Time 44 44Determine pace or beat of a processStd Work 44 44Evaluate tasks done during a processSMED 44 44Single minute exchange of dies-Quick machine set upTPM 44 44Integrate maintenance strategy with processCellular Flow 44 44Reduce inventory&cycle time through process layout and pull production techniquesExpand Process Improvement Program to Utilize Kaizen Tool Kit Tool Kit Comparison7 2000,QualityToolB,LLC,all rights reservednIntroductionnDefects&CostsnWaste ManagementnZero Defect Quality(ZDQ)nUnderstanding Process ErrorsnFour Elements of ZDQnSeven Steps to Poka-Yoke AttainmentnPoka-Yoke MethodsnSummary8 2000,QualityToolB,LLC,all rights reservedWhy is“Zero Defects”an Important Concept?Maintain Customer Satisfaction&LoyaltyHappy Customers mean more sales!9 2000,QualityToolB,LLC,all rights reservedWhy is“Zero Defects”an Important Concept?COSTThere is always a cost associated with manufacturing defects!10 2000,QualityToolB,LLC,all rights reservedCosts of Defects?Does it cost more to make processes better?NOMaking processes better leads to reducedReworkScrapWarranty costsInspection costs11 2000,QualityToolB,LLC,all rights reserved1-10-100 RuleThe 1-10-100 rule states that as a product or service moves through the production system,the cost of correcting An error multiplies by 10.ActivityCost Order entered correctly$1Error detected in billing$10Error detected by customer$100Dissatisfied customer shares the experience with others the costs is$100012 2000,QualityToolB,LLC,all rights reservednIntroductionnDefects&CostsnWaste ManagementnZero Defect Quality(ZDQ)nUnderstanding Process ErrorsnFour Elements of ZDQnSeven Steps to Poka-Yoke AttainmentnPoka-Yoke MethodsnSummary13 2000,QualityToolB,LLC,all rights reservedWhy is“Zero Defects”an Important Concept?Key Element in our capability to eliminate waste.DefectsMisused resourcesInventoriesUntapped ResourcesMotionsDelaysProcesses14 2000,QualityToolB,LLC,all rights reservedWhat is Waste?Everything we do that costs something without adding value to the productOur objective Value added=MaximumNon-Value Added=Minimum15 2000,QualityToolB,LLC,all rights reservedThe nine types of wastenOverproductionnDelays(waiting time)nTransportationnProcessnInventoriesnMotionsnDefective productsnUntapped resourcesnMisused resources 9 Wastes16 2000,QualityToolB,LLC,all rights reservedContinuous ImprovementIs the continuous elimination of waste17 2000,QualityToolB,LLC,all rights reservedElimination of WasteThe MethodCheck and measure resultsIdentify wasteSearch for causesImplement continuous improvement18 2000,QualityToolB,LLC,all rights reservedElimination of Wastes and Continuous ImprovementnElimination of wastesnKAIZENnContinuous ImprovementnOne piece flownSMEDnVisual ControlsnWorkplace OrganizationnKanbannStandard WorknProcess ControlnTotal Productive MaintenancenPoka-YokeLeadtimeCostsQuality the First TimeThe ApproachThe MeansThe Strategy19 2000,QualityToolB,LLC,all rights reservednIntroductionnDefects&CostsnWaste ManagementnZero Defect Quality(ZDQ)nUnderstanding Process ErrorsnFour Elements of ZDQnSeven Steps to Poka-Yoke AttainmentnPoka-Yoke MethodsnSummary20 2000,QualityToolB,LLC,all rights reservedWhat is a Zero Defect Quality System(ZDQ)?A quality concept to manufacture ZERO defects&elimination of waste associated with defects!“ZERO”is the goal!21 2000,QualityToolB,LLC,all rights reservedWhat is a Zero Defect Quality System(ZDQ)?Based on a discipline that defects are prevented.Control the process so that defects are impossible!22 2000,QualityToolB,LLC,all rights reservedWhat is a Zero Defect Quality System(ZDQ)?No Finger Pointing.Operators and Machines will sometimes make mistakes.Find ways to keep errors from becoming defects!23 2000,QualityToolB,LLC,all rights reservedWhat is a Zero Defect Quality System(ZDQ)?A Method for Mistake-Proofing(Poka-yoke)a process.ZDQ assures that defects are not shipped!24 2000,QualityToolB,LLC,all rights reservedHow ZDQ Makes Work EasierMistake-Proof or Poka-yoke the process!Recognize that it is natural for people to make mistakes.25 2000,QualityToolB,LLC,all rights reservedHow ZDQ Makes Work EasierMistake-Proof or Poka-yoke the process!Not noticing that an error is made or a machine is not functioning does not make a person stupid or foolish.26 2000,QualityToolB,LLC,all rights reservedHow Do We Achieve ZDQ?Mistake-Proof or Poka-yoke the process!Errors never become defects!No finger pointing after the fact.No mandate to do better next time.27 2000,QualityToolB,LLC,all rights reservednIntroductionnDefects&CostsnWaste ManagementnZero Defect Quality(ZDQ)nUnderstanding Process ErrorsnFour Elements of ZDQnSeven Steps to Poka-Yoke AttainmentnPoka-Yoke MethodsnSummary28 2000,QualityToolB,LLC,all rights reservedPoka-Yoke results in Quality of Processes Dedicated linesOne piece flowTransformation=Quality production the 1st time Inspection.eliminated?TransportStorageDelay/waitLeadtimeQuality the 1st time Cost29 2000,QualityToolB,LLC,all rights reservedRelationship between processes and quality defects.Almost any business activity can be considered a process.Production processes involve the flow of material.Machining,assembly,and packaging are typical production processes.Business processes involve the flow of information.Financial planning,purchasing&order entry are typical business processes.All processes have the potential for defects.Hence,all processes offer a opportunity for the elimination of defects and the resultant quality improvement.30 2000,QualityToolB,LLC,all rights reservedIn order to reduce quality defects and stop throwing away money,we must Understand the process an its relationship to other business processes.Identify the inputs and outputs of the process.Know who are the suppliers to and customers of the process.=Reduce the variation of the processAnd31 2000,QualityToolB,LLC,all rights reservedWhat Causes Defects?Process Variation From1.Poor procedures or standards.2.Machines.3.Non-conforming material.4.Worn tooling.5.Human Mistakes.Except for human mistakes these conditions can be predicted and corrective action can be implemented to eliminate the cause of defects32 2000,QualityToolB,LLC,all rights reservedWhat Causes Defects?Human MistakesSimple errors-the most common cause of defects-occur unpredictably.The goal of ZDQ is zero!Make certain that the required conditions are in place and controlled to make acceptable product 100%of the time.33 2000,QualityToolB,LLC,all rights reservedTen Types of Human MistakesnForgetfulnessnMisunderstandingnWrong identificationnLack of experiencenWillful(ignoring rules or procedure)nInadvertent or sloppinessnSlowlinessnLack of standardizationnSurprise(unexpected machine operation,etc.)nIntentional(sabotage)34 2000,QualityToolB,LLC,all rights reserved35 2000,QualityToolB,LLC,all rights reservednIntroductionnDefects&CostsnWaste ManagementnZero Defect Quality(ZDQ)nUnderstanding Process ErrorsnFour Elements of ZDQnSeven Steps to Poka-Yoke AttainmentnPoka-Yoke MethodsnSummary36 2000,QualityToolB,LLC,all rights reservedThe 4 Components of ZDQZDQ functions by combining four elementary components:1.Point of Origin Inspection2.100%Audit Checks3.Immediate Feedback4.Poka-Yoke37 2000,QualityToolB,LLC,all rights reservedInspectionThe 3 basic approaches to inspection of processed product are:Judgement/Standard InspectionInformative InspectionPoint of Origin InspectionThe first two approaches are widely used and considered traditional.Only Point of Origin Inspection actually eliminates defects.38 2000,QualityToolB,LLC,all rights reservedPoint of Origin InspectionFocus on prevention,not detection.One of the 4 basic elements of ZDQ.Differs from Judgement and Informative:Catches errorsGives feedback before processingNo risk of making more defective productDetect ErrorFeedback/Corrective ActionProcess with Zero DefectsBy combining Check and Do in the ZDQ approach;the Doing is controlled so it cannot be wrong 100%of the time!May include:Switches that detect miss-fed parts Pins that prevent miss-feeding Warning lights Sound signals39 2000,QualityToolB,LLC,all rights reservedZDQ/Check and Do/Point of Origin InspectionPoint of Origin InspectionCheck for optimum process conditions before processing is done and errors can be made.Instant feedback.Corrections made before defects occur.40 2000,QualityToolB,LLC,all rights reserved100%Audit ChecksPoint of Origin Inspection on every piece.The second of the 4 basic elements of ZDQ.Differs from SQC inspection:Does not rely on samplingPrevents defectsDoes not assume defects will statistically occur100%Audit checks everything on the line!Zero Defects41 2000,QualityToolB,LLC,all rights reservedQuick FeedbackError correction as soon as possibleThe third of the 4 basic elements of ZDQ.Differs from traditional inspection approaches that:Correct problems after the processAddress the problem when errors are already defectsIn some cases never identify an error has occurredZDQ sends the operator a signal and alarms the person that an error has happened!ZDQ Inspections=Immediate Feedback42 2000,QualityToolB,LLC,all rights reservednIntroductionnDefects&CostsnWaste ManagementnZero Defect Quality(ZDQ)nUnderstanding Process ErrorsnFour Elements of ZDQnSeven Steps to Poka-Yoke AttainmentnPoka-Yoke MethodsnSummary43 2000,QualityToolB,LLC,all rights reservedThe Seven Guidelines to Poka-Yoke Attainment1.)Quality Processes-Design“Robust”quality processes to achieve zero defects.2.)Utilize a Team Environment-leverage the teams knowledge,experience to enhance the improvement efforts.3.)Elimination of Errors-Utilize a robust problem solving methodology to drive defects towards zero.4.)Eliminate the“Root Cause”of The Errors-Use the 5 Whys and 2 Hs approach 5.)Do It Right The First Time-Utilizing resources to perform functions correctly the“first”time.6.)Eliminate Non-Value Added Decisions-Dont make excuses-just do it!7.)Implement an Incremental Continual Improvement Approach-implement improvement actions immediately and focus on incremental improvements;efforts do not have to result in a 100%improvement immediately.44 2000,QualityToolB,LLC,all rights reservednIntroductionnDefects&CostsnWaste ManagementnZero Defect Quality(ZDQ)nUnderstanding Process ErrorsnFour Elements of ZDQnSeven Steps to Poka-Yoke AttainmentnPoka-Yoke MethodsnSummary45 2000,QualityToolB,LLC,all rights reservedPoka-yokeMistake-proofing systemsThe fourth of the 4 basic elements of ZDQ.Does not rely on operators catching mistakesInexpensive Point of Origin inspectionQuick feedback 100%of the time“The machine shut down.We must have made an error!”BEEP!BEEP!BEEP!Most Poka-yoke devices are sensor or jig devices that assure 100%compliance all the time!46 2000,QualityToolB,LLC,all rights reservedPoka-yokeWhat is Poke-yoke?A method that uses sensor or other devices for catching errors that may pass by operators or assemblers.Poka-yoke effects two key elements of ZDQ:Identifying the defect immediately(Point of Origin Inspection)Quick Feedback for Corrective ActionHow effective the system is depends on where it is used:Point of Origin or How effective the system is depends on where it is used:Point of Origin or Informative Inspection.Informative Inspection.Poka-yoke detects an error,gives a warning,and can shuts down the process.47 2000,QualityToolB,LLC,all rights reservedPoka-yokePoke-yoke and Point of Origin Inspections(Proactive Approach):A fully implemented ZDQ system requires Poka-yoke usage at or before the inspection points during the process.Poka-yoke will catch the errors before a defective part is manufactured 100%of the time.48 2000,QualityToolB,LLC,all rights reservedPoka-yokePoka-yoke and Informative Inspection(Reactive Approach):Check occurs immediately after the process.Can be an operator check at the process or successive check at the next process.Not 100%effective,will not eliminate all defects.Effective in preventing defects from being passed to next process.Although not as effective as the Source inspection approach,this methodology is more effective than statistical sampling and does provide feedback in reducing defects.49 2000,QualityToolB,LLC,all rights reservedPoka-yoke Systems Govern the ProcessTwo Poka-Yoke System approaches are utilized in manufacturing which lead to successful ZDQ:1.Control ApproachShuts down the process when an error occurs.Keeps the“suspect”part in place when an operation is incomplete.2.Warning ApproachSignals the operator to stop the process and correct the problem.50 2000,QualityToolB,LLC,all rights reservedControl SystemTakes human element out of the equation;does not depend on an operator or assembler.Has a high capability of achieving zero defects.Machine stops when an irregularity is detected.“There must have been an error detected;the machine shut down by itself!”51 2000,QualityToolB,LLC,all rights reservedWarning SystemSometimes an automatic shut off system is not an option.A warning or alarm system can be used to get an operators attention.Below left is an example of an alarm system using dials,lights and sounds to bring attention to the problem.Color coding is also an effective non automatic option.BEEP!BEEP!BEEP!“Im glad the alarm went off,now Im not making defects!”52 2000,QualityToolB,LLC,all rights reservedMethods for Using Poka-yokePoka-yoke systems consist of three primary methods:1.Contact2.Counting3.Motion-SequenceEach method can be used in a control system or a warning system.Each method uses a different process prevention approach for dealing with irregularities.53 2000,QualityToolB,LLC,all rights reservedContact MethodA contact method functions by detecting whether a sensing device makes contact with a part or object within the process.Missing cylinder;piston fully extended alarm soundsContact Method using limit switches identifies missing cylinder.An example of a physical contact method is limit switches that are pressed when cylinders are driven into a piston.The switches are connected to pistons that hold the part in place.In this example,a cylinder is missing and the part is not released to the next process.Cannot proceed to next step.Cylinder present54 2000,QualityToolB,LLC,all rights reservedPhysical Contact DevicesLimit SwitchesToggle Switches55 2000,QualityToolB,LLC,all rights reservedEnergy Contact DevicesPhotoelectric switches can be used with objects that are translucent or transparent depending upon the need.Transmission method:two units,one to transmit light,the other to receive.Reflecting method:PE sensor responds to light reflected from object to detect presence.LightTransmitterReceiverObjectIf object breaks the transmission,the machine is signaled to shut down.56 2000,QualityToolB,LLC,all rights reservedContact DeviceAn example of a contact device using a limit switch.In this case the switch makes contact with a metal barb sensing its presence.If no contact is made the process will shut down.57 2000,QualityToolB,LLC,all rights reservedContact MethodsDo not have to be high tech!Passive devices are sometimes the best method.These can be as simple as guide pins or blocks that do not allow parts to be seated in the wrong position prior to processingTake advantage of parts designed with an uneven shape!A work piece with a hole a bump or an uneven end is a perfect candidate for a passive jig.This method signals to the operator right away that the part is not in proper position.58 2000,QualityToolB,LLC,all rights reservedCounting MethodUsed when a fixed number of operations are required within a process,or when a product has a fixed number of parts that are attached to it.A sensor counts the number of times a part is used or a process is completed and releases the part only when the right count is reached.In the example to the right a limit switch is used to detect and count when the required amount of holes are drilled.The buzzer sounds alerting the operator that the appropriate amount of steps have been taken in the process.59 2000,QualityToolB,LLC,all rights reservedCounting MethodAnother approach is to count the number of parts or components required to complete an operation in advance.If operators finds parts leftover using this method,they will know that something has been omitted from the process.“I have an extra part.I must have omitted a step!”60 2000,QualityToolB,LLC,all rights reservedMotion-Sequence MethodThe third poka-yoke method uses sensors to determine if a motion or a step in a process has occurred.If the step has not occurred or has occurred out of sequence,the the sensor signals a timer or other device to stop the machine and signal the operator.This method uses sensors and photo-electric devices connected to a timer.If movement does not occur when required,the switch signals to stop the process or warn the operator.61 2000,QualityToolB,LLC,all rights reservedMotion-Sequence MethodIn order to help operators select the right parts for the right step in a process the“sequencing”aspect of the motion-step method is used.This is especially helpful when using multiple parts that are similar in size and shape.In this example,each step of the machine cycle is wired to an indicator board and a timer.If each cycle of the machine is not performed within the required“time”and“sequence”,the indicator light for that step will be turned on and the machine will stop.Indicator BoardMachine62 2000,QualityToolB,LLC,all rights reservedTypes of Sensing DevicesSensing devices th
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