《西格玛常识》PPT课件.ppt

1,An Introduction to Six Sigma,2,Six Sigma Achieving Our Objectives,3,The Focus of Six Sigma,Identifying critical aspects of the business with problems or opportunities for improvement. Targeting those critical areas and designating improvement efforts as Six Sigma Black Belt projects. Selecting top people to work on the projects-full time. Ensuring these people have the time, tools, and resources they need to succeed.,4,What Types of Problems Should We Target?,High Defect Rates Low Yields Excessive Cycle Time Excessive Machine Down Time High Maintenance Costs Bottlenecks,5,What Types of Problems Should We Target?,High Defect Rates Low Yields Excessive Cycle Time Excessive Machine Down Time High Maintenance Costs Bottlenecks,Non-Conformance,6,Classes of Non-Conformance,Defects Results when a characteristic does not conform to a standard. Faults Results when a characteristic does not perform to a standard. Errors Results when an action does not comply with a standard.,7,Exercise: Fault, Defect, or Error?,Your pay check is delivered late A unit of media is rejected for a scratch Process cycle time was 22 seconds when machine was delivered by design center. Now running at 29 seconds. Your paycheck is incorrect. You have been overpaid by $200. A technician has not recorded all machine repairs in the maintenance log Too many pieces of test equipment are being calibrated after their calibration expires A piece of test equipment that you want to use is not calibrated Yields are running at 96%, 2% below the requirement.,8,The Role of Measurement,If we cannot express what we know in the form of numbers, we really dont know much about it. If we dont know much about it, we cannot control it. If we cannot control it, we are at the mercy of chance.,Monty Hall shows you 3 boxes on the stage and tells you that under one of the boxes is new car and under the other two boxes are goats. He asks you to pick a box. After you have made your selection he reveals under one of the two remaining boxes a goat. He asks you if you would like to change your selection. Should you? Does it matter? If you change will it improve your chances to win the car?,Suppose you are on Lets Make a Deal,Door # 1,Door # 2,Door # 3,ASK MARILYN,You are in error-and you have ignored good counsel-but Albert Einstein earned a dearer place in the hearts of the people after he admitted his errors. Frank Rose, Ph.D., University of Michigan Your logic is in error, and I am sure you will receive many letters on this topic from high school and college students. Perhaps you should keep a few addresses for help with future columns. W. Robert Smith, Ph.D., Georgia State University You are utterly incorrect about the game-show question, and I hope this controversy will call some public attention to the serious national crisis in mathematical education. If you can admit your error, you will have contributed constructively toward the solution of a deplorable situation. How many irate mathematicians are needed to get you to change your mind? E. Ray Bobo, Ph.D., Georgetown University Maybe women look at math problems differently than men. Don Edwards, Sunriver, Or Youre wrong, but look on the positive side. If all those Ph.D.s were wrong, the country would be in very serious trouble. Everett Harman. Ph.D. US. Army Research Institute You are indeed correct. My colleagues at work had a ball with this problem, and I dare say that most of them-including me at first-thought you were wrong! Seth Kaleon, Ph.D., Massachusetts Institute of Technology Parade Magazine, Feb. 1991,When Intuition Leads Us Down the Wrong Path Data Can Set Us Straight,Do Not Change Change,I II III,12,Customer Focus: A Model For Success,Technology,Technology,Capability,Capability,Organization,Organization,People,People,Processes,Processes,Business survival is dependent upon how well we satisfy our customers. Customer satisfaction is a function of quality, price, and delivery. Quality, cost, and prompt delivery are dependent upon capability.,13,The Customer Supplier Interaction,We strive for Six Sigma capability on Cycle Time, Cost, and Conformance to meet customer expectations on Delivery, Price, and Quality.,14,How Does Six Sigma Make the Difference?,Vision Philosophy Aggressive goal Metric (standard of measurement) Method Vehicle for: Customer focus Breakthrough improvement Continuous improvement People Involvement,15,Six Sigma Vision,The Vision of Six Sigma is to delight customers by delivering world-class quality products through the achievement of Six Sigma levels of performance in everything we do.,16,Six Sigma Philosophy,The philosophy of Six Sigma is to apply a structured, systematic approach to achieve breakthrough improvement across all areas of our business.,17,Sigma is a statistical unit of measure that reflects process capability. The sigma scale of measure is perfectly correlated to such characteristics as defects-per-unit, parts-per million defective, and the probability of a failure/error.,PPM,Process Capability,Defects per Million Opp.,Six Sigma - Aggressive Goal,18,Statistical Definition of Six Sigma,LSL,LSL,USL,USL,Process Width,m,o,Design Width,+ 3,s,st,T,T,.001,ppm, USL,.001,ppm, LSL,scale,LSL,LSL,USL,USL,scale,T,T,+ 6,s,st,scale,m,Point of Inflection,1s,T,USL,p(d),p(d),1 2 3 4 5 6,s,The Standard Deviation,20,3 Sigma,6 Sigma,5 Sigma,4 Sigma,93.32 %,99.379 %,99.9767 %,99.99966 %,Historical,Current,Intermediate,Long-Run,Sigma,Long-Term Yield,Standard,Six Sigma - Performance Target,21,99.99966% Good (6 Sigma),20,000 lost articles of mail per hour Unsafe drinking water for almost 15 minutes each day 5,000 incorrect surgical operations per week Two short or long landings at most major airports each day 200,000 wrong drug prescriptions each year No electricity for almost seven hours each month,Seven articles lost per hour One unsafe minute every seven months 1.7 incorrect surgical operations per week One short or long landing every five years 68 wrong prescriptions per year One hour without electricity every 34 years,99% Good (2.8 Sigma),Six Sigma - Practical Meaning,22,Characterize Optimize Breakthrough,USL,T,LSL,USL,T,LSL,T,USL,LSL,USL,LSL,The Strategy,23,Characterization,Phase 1:,Measurement,Phase 2:,Analysis,Optimization,Phase 3:,Improvement,The Breakthrough Phases,24,Six Sigma-Methodology,Optimized Process,30 - 50,10 - 15,4-8,Key Process Input,Variables (,KPIVs,),8 - 10,KPIVs,Critical,KPIVs,Inputs Variables,Process Map,Multi-,Vari,Studies,Correlations,Screening,DOEs,DOEs, RSM,C&E Matrix and FMEA,Gage R&R, Capability,T-Test, ANOM, ANOVA,Quality Systems,SPC, Control Plans,Measure,Analyze,Improve,Control,Narrow the scope of input variables ID leveraged KPIVs,25,If we are so good at X, why do we constantly test and inspect Y?,Y Dependent Output Effect Symptom Monitor,X1 . . . XN Independent Input-Process Cause Problem Control,To get results, should we focus our behavior on the Y or X?,f (X),Y=,Focus on X rather than Y, as done historically,The Focus of Six Sigma,26,The Breakthrough Strategy,A,B,C,D,E,F,G,Application Projects,Breakthrough Cookbook,Recognize,Define,Goal:,Measure,Analyze,Improve,Control,27,Time,Performance,GOOD,BAD,3 Sigma,6 Sigma,This Drives Breakthrough Improvement,Six Sigma Breakthrough,28,What level are you at?,The Foundation of the Six Sigma Tools,29,What is Cost of Poor Quality?,In addition to the direct costs associated with finding and fixing defects, “Cost of Poor Quality” also includes: The hidden cost of failing to meet customer expectations the first time The hidden opportunity for increased efficiency The hidden potential for higher profits The hidden loss in market share The hidden increase in production cycle time The hidden labor associated with ordering replacement material The hidden costs associated with disposing of defects For most companies today, the cost of poor quality is likely to be 25 % of sales. For Seagate, thats over $1 billion each year. In almost every company where the COPQ is unknown, the COPQ exceeds the profit margin.,30,Impact of Variation on Cost,Goal Post Metality,31,CTXs(Cost, Quality, Delivery, Satisfaction) Defects Per Unit Complexity Defects Per Million Opportunities Rolled Thruput Yield Rolled Thruput Yield Normalized Sigma Score Process Baseline Process Entitlement Process Benchmarking KPIVs KPOVs Shift & Drift,Six Sigma Metrics,Existing Metrics,Yield Scrap Rework ? ? ? ? ?,Leadership Must Ask the Right Questions What Gets Measured Gets Managed,Six Sigma Metrics,32,Six Sigma Metrics - Definitions,CTxs: Critical to Customer Satisfaction parameters. Typically, these include, but are not limited to, cost, quality and delivery KPOVs: Key Process Output Variables. The results of the collective action of KPIVs in a process on a product KPIVs: Key Process Input Variables. Those process variables that directly and/or in conjunction with other KPIVs, drive a change in an output variable,33,CTXs,CT = “Critical To” CTS - Critical To achieving customer Satisfaction. Typically, this includes, but is not limited to, those parameters which are CTQ - Critical to Quality CTD - Critical to Delivery CTC - Critical to Cost Six Sigma Leads you to the “Criticals” to Increase the Efficiency of the Improvement ProcessWork on What is Important,34,Key Process Variables,KPOVs: Key Process Output Variables The process outputs critical to achieving the CTXs, In Golf as an Example Distance hit or degrees off line from tee to hole KPIVs: Key Process Input Variables Those process variables that directly or in combination with other input variables produce a direct effect in a KPOV Club selection, stance, backswing velocity, club face angle, wrist action, follow-through Six Sigma Leads you to the “Criticals” to Increase the Efficiency of the Improvement ProcessWork on What is Important,35,Six Sigma Metrics - Definitions,Process Baseline: The average, long term defect level of a process when all input variables in the process are running in an unconstrained fashion Process Entitlement: The best case, short term defect level of a process when all input variables in the process are centered and in control Process Benchmark: The defect level of the process deemed by comparison to be the best process possible,36,Process Baseline,Process Baseline: The average, long term defect level of a process when all input variables in the process are running in an unconstrained fashion,Long-term Baseline,37,Process Entitlement,Process Entitlement: The best case, short term defect level of a process when all input variables in the process are centered and in control,38,Process Benchmark,Process Benchmark: The defect level of the process deemed by comparison to be the best process possible,Factory A,Factory B,Factory C,39,Six Sigma Metrics - Definitions,Shift: Step function change in the mean or average of a population, often driven by a special cause or movement in a key process input variable Drift: Sustained trend in a mean or average of a population, often due to a progressive change to an key process input variable,40,Shift & Drift,Shift: Step function change in the mean or average of a population, often driven by a special cause or movement in a key process input variable,41,Shift & Drift,Drift: Sustained trend in a mean or average of a population, often due to a progressive change to an key process input variable,42,Six Sigma Metrics - Definitions,Defects per Unit: The total number of defects observed on a unit of output Opportunities: The number of possibilities for defect creation in a process or sequence of processes. DPMO: Defects per million opportunities,43,Manufacturing Variation Causes A “Hidden Factory“ Increased Cost - Lost Capacity,Yield After Inspection or Test,Each defect must be detected, repaired and placed back in the process. Each defect costs time and money.,Scrap,Rework,Hidden Factory,NOT OK,Operation,Inputs,Inspect,First Time Yield,OK,Wasted Time Wasted Money Wasted Resources Wasted Floor space,Defects and the Hidden Factory,44,RTY Versus FTY,66% 90% . why not?,Process,A,B,C,90% Yield,90% Yield,90% Yield,Rolled Yield,81 %,73 %,90% Yield,Final Test D,66 %,Using “final test (or first time) yield” ignores the hidden factory. Final test performance is a function of inspection & test not actual defect data.,Rolled-Throughput Yield,Classical First-Time Yield,45,Two Types of Defect Models,Uniform Defect:,The same type of defect appears,within a unit of product; e.g., wrong type of steel.,Random Defect:,The defects are intermittent and,unrelated; e.g., flaw in surface finish.,Conclusion:,The use of a random,model to describe,the occurrence of,defects is plausible.,Conclusion:,The use of a random,model to describe,the occurrence of,defects is plausible.,Random,Uniform,Universe of Defects,Universe of Defects,46,Defects per Unit,Defects per Unit (DPU): Average number of defects per unit produced,DPU: 7 Defects / 5 Units = 1.4 Defects per Unit,47,Opportunities,Opportunities: The number of possibilities for defect creation in any unit of product, process or sequence of processes.,1. OD Dimension 2. ID Dimension 3. Flatness 4. Roughness 5. Coercivity 6. Carbon Thickness 7. Lube Thickness 8. Glide Height,8 Opportunities,48,1. OD Dimension 2. ID Dimension 3. Flatness 4. Roughness 5. Coercivity 6. Carbon Thickness 7. Lube Thickness 8. Glide Height,Opportunities,Opportunities: The number of possibilities for defect creation in any unit of product, process or sequence of processes.,8 x 5 = 40 Opportunities,DPMO: Defects per Million Opportunities,49,Six Sigma Metrics - Definitions,Classical Yield: The number of good units divided by the number of units tested or inspected Rolled Throughput Yield (RTY): The probability of a unit going through all process steps with zero defects. This is used to identify and quantify the “Hidden Factory” Hidden Factory: The amount of work above and beyond the requirements necessary to produce a unit of output,50,Classical Yield,Factory,In,Out,Scrap,Yield =,Out In,The number of good units produced which have no defects, divided by the number of units started, tested or inspected.,51,Classical Yield,Factory A,100,85,15,Scrap,Factory B,100,85,Not all Yields are alike!,52,Classical Yield,Factory A,100,85,15,Scrap,Factory B,100,85,15 Scrap,Rework,Factory C: The Hidden Factory,Not all Yields are alike!,50,35,53,Classical Yield,Factory A,100,85,15,Scrap,Factory B,100,85,15 Scrap,Rework,Factory C: The Hidden Factory,Not all Yields are alike!,50,35,Equal Yields Unequal Costs Classical Yield does not correlate to cost, cycle time or inventory levels,54,Rolled Thruput Yield,Process 1,1000,950,Process 2,930,Process 3,820,Process 4,810,Rework,90,50,20,110,10,900,95.0%,47.4%,97.9%,88.2%,98.8%,90.0%,The probability of going through all process steps with zero defects,55,Rolled Thruput Yield,Process 1,1000,950,Process 2,930,Process 3,820,Process 4,810,Rework,90,50,20,110,10,900,95.0%,47.4%,97.9%,88.2%,98.8%,The probability of going through all process steps with zero defects,Yrt = (.950)*(.979)*(.882)*(.988) = 81.0%,90.0%,56,Rolled Thruput Yield,Process 1,1000,950,Process 2,930,Process 3,820,Process 4,810,Rework,90,50,20,110,10,900,95.0%,47.4%,97.9%,88.2%,98.8%,The probability of going through all process steps with zero defects,Yrt = (.950)*(.979)*(.882)*(.988) = 81.0%,90.0%,Correlates to cost, cycle time, and inventory levels,57,Yield Comparison,Final Classical Yield - Rolled Thruput Yield,Hidden Factory,=,58,An Average Measure,How do we measure the relative performance of a process?,Factory A,Yrt = 80.1%,Factory B,Yrt = 77.3%,Which factory is Better?,59,An Average Measure,Its a TRICK QUESTION,Factory A,Yrt = 80.1%,Factory B,Yrt = 77.3%,95%,94%,96%,98%,92%,90%,89%,Factory B runs higher average yields at each step,60,Six Sigma Metrics - Definitions,Normalized Throughput Yield: The yield for a total process averaged over all process steps Complexity: A measure of how complicated a process or product isthe more opportunities for defects a process or product has, the more complex it is.,61,Normalized Thruput Yield,Factory A,Yrt = 80.1%,Factory B,Yrt = 77.3%,95%,94%,96%,98%,92%,90%,89%,The yield for a total process averaged over all process steps (Yna),Yna = (Yrt)1/n,Yna = (.801)1/2 = 89.5%,Yna = (.773)1/5 = 95.0%,62,Normalized Thruput Yield,Factory A,Yrt = 80.1%,Factory B,Yrt = 77.3%,95%,94%,96%,98%,92%,90%,89%,The yield for a total process averaged over all process steps (Yna),Yna = (Yrt)1/n,Yna = (.801)1/2 = 89.5%,Yna = (.773)1/5 = 95.0%,“n” is the COMPLEXITY. As process steps or the number