Focused appraisal with formal methods/techniques. FMEA stands for. FMEA Purpose. What is FMEA? Failures. Time. Introduction. GQ Huang (HKU) FMEA-QFD-1

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1 FMEA-QFD-1 Focused appraisal with formal methods/techniques General understanding of the product. What does the product look like? What does the product consists of? How (well) does the product work and how is it used?? Lifecycle appraisal with Design for X What makes a good product I? - Key Performance Indicators What makes a good product II? - Key Product Characteristics What makes a good product III? - Key Process Characteristics Design for X Safety, Environment, Manufacture and Assembly, Ergonomics and Esthetics etc. Focused appraisal with formal methods/techniques FMEA QFD Market and Technology Appraisal Perception Mapping Market segmentation Product life cycle FMEA stands for Failure Modes and Effect Analysis Introduction FMEA-QFD-3 FMEA-QFD-4 What is FMEA? FMEA Purpose s and Effects Analysis (FMEA) is a structured analytical technique for assessing risk during product development to identify early corrective action. Structured group of activities which... Identify potential failure modes Prioritize actions Document the process. Failures FMEA Time FMEA-QFD-1

2 FMEA-QFD-5 FMEA-QFD-6 Typical Applications of FMEA? What benefits does FMEA bring? From very simple products To very sophisticated products Aerospace Automotive Chemical processes Nuclear Consumer products Software products Service products Etc. Early identification of problems Right first time design Reduced scrap Improved product reliability Reduced warranty returns Appropriate recommended actions may not have been taken. Savings in engineering time. Reduction of changes immediately before production start (Commercial Release). FMEA-QFD-7 FMEA-QFD-8 Brief History of FMEA Overview of FMEA Worksheet It has been the result of continuous crystalization of good practices in design engineering, quality and reliability engineering. 1920s Good practices start emerge 1950s Become standards in USA and UK 1970s-1980s Widely adopted across the industrial spectrum Usually intensive short-course training very expensive Since 1990s Contractual requirements in several industrial sectors Widely taught to college students FMEA Number Prepared By FMEA Component Starlock Washer Assembly Design Key Effect H/Lamp Adjuster Core Team FMEA-QFD-2

3 FMEA-QFD-9 FMEA-QFD-10 FMEA Analysis Procedure Determine s and their s Part Failure mode Effect Effects Cause Design Control Calculate s Rating Rating Rate Similar to what we have discussed on using BOM for al Analysis. List all product items (in the form of BOM) Identify and describe all functions for each = Risk Priority Number Robust Design FMEA-QFD-11 FMEA-QFD-12 Describe How does it fail? Verb Noun Effect Indicates action, occurrence, being Generate Control Display Indicates what the action relates to light speed information Consider the s of Body of Ball-Point Pen. Consider the s of Tube Sub-Assembly of Ball- Point Pen. FMEA-QFD-3

4 FMEA-QFD-13 FMEA-QFD-14 Effects of Failure (Modes) Consequence/Impacts Effects of Failure (Modes) Examples Effect Effect What are the effects of the failure relating to: another part the complete assembly the customer the enduser the governmental regulations Consider the Effects of the - Not comfortable to hold of Body of Ball-Point Pen. Consider the Effects of the Irregular/messy lines of Tube Sub-assembly of Ball-Point Pen. FMEA-QFD-15 FMEA-QFD-16 (S) How Serious? FMEA Rating Criteria Effect Effect of Failure Cause of Failure Design How bad is it? How often? What checks? Consider the Effects of the - Not comfortable to hold of Body of Ball-Point Pen. Bad writing - Concerned Painful fingers - Concerned Consider the Effects of the Irregular/messy lines of Tube Sub-assembly of Ball-Point Pen. Bad report -> Loose job -> Extremely serious RATING SEVERITY Hardly Noticeable Dissatisfaction Serious Effects OCCURRENCE Almost Never Occasionally Often DETECTION Absolutely Obvious Could Go Unnoticed Undetectable FMEA-QFD-4

5 FMEA-QFD-17 FMEA-QFD-18 Cause of Failure What causes the failure? Cause of Failure Sources of the Cause Effect Effect Consider the Cause(s) of the - Not comfortable to hold of Body of Ball-Point Pen. Consider the Cause(s) of the Irregular/messy lines of Tube Sub-assembly of Ball-Point Pen. A cause may be rooted at the Design Stage Under designed A cause may be rooted at the Production/Delivery Stage Poor quality control A cause may be rooted at the Use Stage Improper uses FMEA-QFD-19 FMEA-QFD-20 Manufacturing misbuilds Manufacturing misbuilds Due to design Deficiencies Robust Design FMEA-QFD-5

6 FMEA-QFD-21 FMEA-QFD-22 (O) How often does it cause the failure? FMEA Rating Criteria Effect Effect of Failure Cause of Failure Design How bad is it? How often? What checks? Consider the Cause(s) of the - Not comfortable to hold of Body of Ball-Point Pen. Shape Cross Section (Design, O = 1) RATING SEVERITY OCCURRENCE DETECTION Consider the Cause(s) of the Irregular/messy lines of Tube Sub-assembly of Ball-Point Pen. Tolerance between Ball and Seat is too large (Manufacturing, O = 6) Temperature is too high (Use Environment, O = 7) Hardly Noticeable Dissatisfaction Serious Effects Almost Never Occasionally Often Absolutely Obvious Could Go Unnoticed Undetectable FMEA-QFD-23 FMEA-QFD-24 Design and Methods How do you detect the failure? Design (D) Effect Effect How do you detect the failure Uneven line thickness of Ball- Point pen? Visual observation How do you detect the tolerance of the gap between the Ball and Seat of Ball-Point pen? Special equipment How do you detect the failure Uneven line thickness of Ball- Point pen? Visual observation Very Easy (1) How do you detect the tolerance of the gap between the Ball and Seat of Ball-Point pen? Special equipment Very Difficult and Expensive Need to be professionally done (9) FMEA-QFD-6

7 FMEA-QFD-25 FMEA-QFD-26 FMEA Analysis Criteria - - Risk Priority Numbers RATING Effect of Failure Cause of Failure Design How bad is it? SEVERITY Hardly Noticeable Dissatisfaction Serious Effects How often? OCCURRENCE Almost Never Occasionally Often What checks? DETECTION Absolutely Obvious Could Go Unnoticed Undetectable Effect (Mode) = S * O * D (Product of S, O and D ratings) () = Sum of s of all the failure modes. () = Sum of s of all the functions (Product) = Sum of s of all the items What should be done if a has more than one Effects/Causes/s? FMEA-QFD-27 FMEA-QFD-28 Interpreting s FMEA Results Planning for Effect Effect The higher the is, the... The lower the is, the... should be recommended for those items with higher s. More design time and efforts should be allocated and dedicated to items with higher s. Identify those functions and items with high s. Recomend actions in order to Eliminate the cause of failure Minimize the effect of failure Reduce the frequency of failure/cause Faciltate failure detection and control Faciltate failure recovery Etc. FMEA-QFD-7

8 FMEA-QFD-29 FMEA-QFD-30 Managing FMEA s Determining Causes & Effects Effect Effect Who should take the recommended action(s)? When should the action(s) start and finish? What effect may the failure have? Effect How could it fail? What may cause the failure? Mode of Failure Cause What process or system or controls are in place to identify or prevent a failure? FMEA-QFD-31 FMEA-QFD-32 Example - Headlamp Adjuster Example - Headlamp Adjuster Knob Insert Effect Screw Starlock washer Rubber washer Headlamp body Secures the insert and Rubber washer assembly into the headlamp body Falls off due Flips to reverse to reduced grip angle on insert Cracks Falls off due to reduced grip on insert Material too thin to support rubber Insert diameter too small to create correct locking angle 2 2 Proven principle Known design principle Washer inner Supplied diameter too big 2 proprietary item 1 16 Excessive assy force due to oversize insert dia Incorrect heat treatment specified 2 Known design principle proprietary item 3 48 Supplied FMEA-QFD-8

9 FMEA-QFD-33 Example - Ball-Point Pen Effect QFD stands for Quality Deployment FMEA-QFD-35 FMEA-QFD-36 What is QFD? QFD Purpose Translates the voice of the customer into the will of the enterprise. Customer s voice in the language of the customer Will of the enterprise in the technical language of design and manufacturing Translate consumer s voice into technical design requirements Determine & prioritize customer needs Translate customer needs to product design parameters Coordinate efforts and skills of an organization from a project s inception to its completion Cobe1 Ensure customer expectations Avoid manufacturing catastrophe FMEA-QFD-9

10 Slide 36 Cobe1 QFD enables an organization to direct efforts on customer requiremtnts for which a product might not be competitive thus activites in the company are prioritized according to the level of concern for customer satisfaction COBEguest, 27/04/2002

11 FMEA-QFD-37 FMEA-QFD-38 History Cobe2 QFD can be used to: 1972 Japan Mitsubishi Introduced to USA To Europe Part of Total Quality Management Valuable tool Underused Fundamental to success Reduce product development time by 50% Cut start-up & engineering costs by 30% Reduce time to market Reduce # of design changes Lower rework Reduce facility s maintenance/operation costs Improve quality FMEA-QFD-39 FMEA-QFD-40 More Benefits Benefits of QFD Improved client Satisfaction Reduced Development Time Improved Internal Communications Better Documentation of Key Issues Save $$ Money $$ 25,000 professionals and over 500 companies have realized major improvements in client satisfaction using QFD, achieving: a method to "design-in" quality proactively reduced changes in product/process development identified need for changes before making major expenditures reduced product development time fewer start-up problems reduced field problems reduced warranty costs creation of a design knowledge base integrating the "Voice of the client" into the development process company understanding of client's needs, even better than the clients themselves do For those professionals committed to driving the "voice of the client" into their products and services, this method will: Increase client satisfaction Reduce the number of design changes Reduce variability throughout the development cycle Reduce the number of start-up problems Reduce the total development time Create a proprietary client-driven database of knowledge for the organization Products meet customer expectations better Provides improved design traceability Reduced lead times through fewer design changes and focus on key features Reduced product cost through use of appropriate tolerances and reduced scrap Improved communication within organisation and with customer BEFORE QFD Individual Work Some client Focus "Over the Wall" Development Supports Simultaneous Engineering Poor Documentation Supports AFTER QFD Cross-functional Teams Intense client Focus Integrated Product Development Poor Communications Better Communication/ Documentation FMEA-QFD-10

12 Slide 37 Cobe2 QFD was concieved in 1972 by the Japanese company, Mitsubishi Heavy Industries Ltd. as part of their TQM system. COBEguest, 27/04/2002

13 FMEA-QFD-42 The House of Quality Quality Deployment Roof Technical Requirements The House of Quality The QFD Worksheet Customer Requirements Inter relationships Market / Customer Priorities Market Benchmarking Technical Priorities Technical Benchmarking Technical Targets FMEA-QFD-43 FMEA-QFD-44 Typical QFD 1 Chart QFD 1 Analysis Procedure Market /Product Strategy Customer Requirements Priority Setting Design Requirements Target Values Relationship Setting Competitor Benchmarking Technical Benchmarking Complete Matrix Define Product Plan & Specification Note : QFD is a highly iterative process. Involvement from Customers is vital though out FMEA-QFD-11

14 FMEA-QFD-45 FMEA-QFD-46 QFD process Key Steps Pencil Example Identify customer requirements Importance ratings Competitor assessment Derive design requirements Target values Correlation Competitor benchmarking Plot relationships Prioritise design requirements Importance Weighting Cross section Paint Lead Tube material Length Label Market Priorities Technical Trend Technical difficulty Does not roll 7 18 Does not smell Comfort of holding 8 Technical Priorities Existing Competitor #1 Competitor #2 Target System Existing Competitor #1 Competitor #2 FMEA-QFD-47 FMEA-QFD-48 Pencil Example Customer Requirements Importance Weighting Cross section Paint Lead Tube material Length Technical Trend Technical difficulty Does not roll 7 Does not smell 5 Comfort of holding 8 Technical Priorities Existing Competitor #1 Competitor #2 Target System Label Market Priorities Existing Competitor #1 Competitor #2 Identify stakeholders Determine Customer Requirements Group customer requirements Identify principal customer Determine Importance Ratings FMEA-QFD-12

15 FMEA-QFD-49 FMEA-QFD-50 Customer Requirements Design Requirements Can you think of one more example from Pencil Retailer s point of view? Importance Weighting Does not roll 7 Does not smell Comfort of holding 8 Derive design requirements from customer requirements Group Design Requirements Technical trends The larger the better The smaller the better Target value is the best. Technical difficulties Cost of implementation Etc. FMEA-QFD-51 FMEA-QFD-52 Design Requirements Relationships Technical Trend Importance Weighting Cross section Paint Lead Tube material Length Label Identify strong, medium & weak relationships Does the design requirement help to satisfy the customer requirement? Work along rows Important rows first Prioritise design requirements Technical difficulty Does not roll 7 Does not smell Comfort of holding 8 FMEA-QFD-13

16 FMEA-QFD-53 FMEA-QFD-54 Interrelationships Interrelationships Between customer requirements and technical requirements Translation and correlation step Critical to generate consensus between development team and customers. Critical Question: How significant is technical requirement A in satisfying customer requirement B? - Strong -Medium -Weak Blank No relation? Relationship undefined. Technical Trend Technical difficulty Importance Weighting Cross section Paint Lead Tube material Length Label Does not roll 7 Does not smell Comfort of holding 8 FMEA-QFD-55 FMEA-QFD-56 Market / Customer Priorities Technical Priorities - Strong - Medium -Weak Blank No relation? Relationship undefined. Technical Trend Technical difficulty Importance Weighting Cross section Does not roll 7 18 Paint Lead Tube material Length Does not smell Comfort of holding 8 Label Market Priorities - Strong -Medium -Weak Blank No relation? Relationship undefined. Importance Weighting Cross section Technical Trend Technical difficulty Does not roll 7 18 Does not smell Comfort of holding 8 Technical Priorities Paint Lead Tube material Length Label Market Priorities FMEA-QFD-14

17 FMEA-QFD-57 FMEA-QFD-58 Interpreting QFD Results The Roof Rows with higher priorities Rows with lower priorities Considers impact of technical requirements on each other Feature to feature comparison Augment or impede? Columns with lower priorities Columns with lower priorities Purpose: Tradeoff between technical requirements Critical Question: Does improving one requirement cause a deterioration or improvement in another requirement? FMEA-QFD-59 FMEA-QFD-60 The Roof Competitive (Market) Benchmarking Legend + Positive supporting - Negative tradeoff Importance Weighting Cross section Paint Lead Tube material Length Label Existing Market Priorities Competitor #2 Competitor #1 Technical Trend Meets standards Harness weight Webbing strength Padding thickness Webbing strength Padding thickness Technical difficulty Does not roll Does not smell Comfort of holding 8 Technical Priorities FMEA-QFD-15

18 FMEA-QFD-61 FMEA-QFD-62 Competitive (Technical) Benchmarking Technical Targets Technical Trend Importance Weighting Cross section Paint Lead Tube material Length Label Market Priorities Technical difficulty Does not roll 7 18 Does not smell Comfort of holding 8 Existing Competitor #1 Competitor #2 Summarize previous steps Draw conclusions Consists of: Technical Priorities Competitive Benchmarks Final Product Targets Results from previous steps: Customer requirements Prioritized customer requirements Technical requirements Correlated requirements Feature interdependencies Technical Priorities Existing 3 5 Competitor #1 2 3 Competitor #2 5 2 FMEA-QFD-63 FMEA-QFD-64 Technical Targets House of Quality Summary Importance Weighting Cross section Paint Lead Tube material Length Label Market Priorities Technical Trend Technical difficulty Does not roll 7 18 Does not smell Comfort of holding 8 Technical Priorities Existing Competitor #1 Competitor #2 Target System Existing Competitor #1 Competitor #2 Inputs: Customer requirements Technical requirements Customer priorities Market reality / competitive analysis Organization s strengths & weaknesses Outputs Prioritized technical requirements Measurable, testable goals FMEA-QFD-16

19 FMEA-QFD-65 FMEA-QFD-66 House of Quality Pros and Cons Closures Pros: Generates specific technical requirements Requirements are traceable Follows a repeatable, quantitative process Effectively translates Voice of the Customer Records rationale for each technical requirement Cons: Time-consuming process for >10 requirements Data storage, manipulation and maintenance costs Very dependent on customer requirement gathering Inflexible to changing requirements; must recalculate Customers tell us that they like closures that are: Easy to open Easy to close, AND Customers also tell us that they dislike Road noise Water leaks FMEA-QFD-67 Summary-QFD & The House Helps engineers to choose engineering characteristics of and set targets related to product performance. Forces tough decisions and trade-offs to be addressed early in the PDP. Serves as a corporate memory of important issues related to product innovation. Phases of QFD QFD applies not only to product planning stage, but also downstream stages FMEA-QFD-17

20 FMEA-QFD-69 FMEA-QFD-70 Deploying CA s Downstream The Phases of QFD Phase 1 Product Planning Phase 2 Part Development Phase 3 Process Planning Phase 4 Production Planning Design Requirements Part Characteristic Process Operations Production Requirements The house of quality can be used to deploy the voice of the customer to all elements of the product realization process. Customer Wants Key Design Requirements Key Part Characteristics Key Process Operations 1 FMEA-QFD-72 FMEA and QFD Managing FMEA and QFD They are team-building tools. They must be used as such in order to Facilitates communication between Customers Marketing Product development Engineering Manufacturing, and Service Are design tools, which Facilitates communication between Customers Marketing Product development Engineering Manufacturing, and Service FMEA-QFD-18

21 FMEA-QFD-73 FMEA-QFD-74 Team Generating FMEA/QFD Facilitator Who initiates? Who prepares? Who updates? Design- Enginieer Production/ process-enginieer Coreteam Support team Representitives from: development production quality purchase testdept. When to discard? How documented? When completed? FMEA/QFD Who is FMEA/QFD - customer? Startingdate/ revisiondate?... FMEA-QFD-75 FMEA Team Approach Car Door Case Study Coreteam Supportteam FMEA-QFD-19

22 FMEA-QFD-77 FMEA-QFD-78 To Learn More Voice of the Customer-CA s Houser, J.R., D.P. Clausing, The House of Quality, Harvard Business Review, vol. 66, no. 3, pp. May-June 1988, D.P. Clausing, Total Quality Development, ASME Press, 1994 What does the Customer REALLY Mean? Quiet? Easy? What is a water leak? Customer Attributes Stated in the language of the customer Usually must be decomposed FMEA-QFD-79 FMEA-QFD-80 CA s for a Car Door Easy to Open and Close Good operation and use Easy to open and close door Isolation Arm rest Easy entrance and exit Good appearance Interior trim Clean Fit Door Easy to close from outside Easy to close from inside Easy to open from outside Easy to open from inside Stays open on a hill Doesn t kick back FMEA-QFD-20

23 FMEA-QFD-81 FMEA-QFD-82 Easy to Open and Close Isolation Window Secure from outside Can be opened by owner only from outside Easy to open from inside Easy to close from outside Easy to close from inside Other issues like door No road noise No wind noise Doesn t rattle Doesn t let in rain Doesn t leak in car wash Doesn t drip in moisture when open FMEA-QFD-83 FMEA-QFD-84 Arm Rest Easy Entrance and Exit Soft Comfortable Correct position Convenient to enter and be seated Driver Passengers Convenient to exit Child safety Front Rear Windows FMEA-QFD-21

24 FMEA-QFD-85 FMEA-QFD-86 Interior Trim Clean Material won t fade Attractive Sturdy Stain resistant Warm in winter Cool in summer Easy to clean No lubricant from door No dust from closure FMEA-QFD-87 FMEA-QFD-88 Fit Customers-Who are They? Uniform gap between matching surfaces Appealing design End users Service Assembly Suppliers Every step of the supply chain has CA s Products should be easy to manufacture, assemble, service and use FMEA-QFD-22

25 FMEA-QFD-89 FMEA-QFD-90 CA Weights The Competition? Customer attributes (preferences) are normally not equally important. Add weights to show relative importance CA s may conflict! Easy to close door Quickly closing window Heavier motor Weights allow CA s to be prioritized. How are we doing (or plan to do) relative to the competition? Market segmentation East coast Mid-west West coast Economy luxury FMEA-QFD-91 FMEA-QFD-92 Product Perceptual Map Engineering Characteristics-EC s Provides link between product concept and company s strategic vision. Customers (marketing) tell us what to do. Engineering tells us how to do it. Let the design team list the EC s that may affect the CA s. Some EC s may affect several CA s. EC s express how we plan to satisfy customer requirements (CA S). EC s should describe the product in measurable terms that directly affect CA s. FMEA-QFD-23

26 FMEA-QFD-93 FMEA-QFD-94 Creating the House of Quality Relationship Matrix FMEA-QFD-95 FMEA-QFD-96 Relationship Matrix Relationship Matrix Shows the relationship between the CA s and EC s. Team reaches consensus on weights or + indicates positive relationship X or indicates negative relationship After linking the voice of the customer (CA s) to engineering actions (EC s), the team adds objective measures (in engineering units) and targets below the house. FMEA-QFD-24

27 FMEA-QFD-97 FMEA-QFD-98 Roof Shows Trade-offs Trade-offs Must be Considered Indicates a negative relationship between energy to close door and door seal resistance. Closures present a serious challenge Interaction is the rule not the exception! Closing effort door seal resistance road noise Door seal resistance + road noise We must consider cost and technical feasibility. FMEA-QFD-99 Cost and Targets FMEA-QFD-25