05 Fmea(失效模式及后果分析).ppt

1、Six Sigma Champion Training,1,Failure Modes and Effects Analysis,Champion Training,Six Sigma Champion Training,2,A FMEA is a disciplined procedure that allows the engineer to anticipate failures and prevent their occurrence in manufacturing.,Identify ways the product or process can fail. Then plan t

2、o prevent those failures.,Concept,What is a FMEA?,Six Sigma Champion Training,3,System FMEA: Used to analyze systems and subsystems in the early concept and design stages. Focuses on potential failure modes associated with the functions of a system caused by design. Design FMEA: Used to analyze prod

3、ucts before they are released to production. Process FMEA: Used to analyze manufacturing and assembly processes.,Types of FMEAs,Six Sigma Champion Training,4,Cause 1,Cause 2,Effect 1,Cause 1,C & Es may be related in different ways.,Important to Understand the Cause & Effect Relationship,Six Sigma Ch

4、ampion Training,5,Linking Failure Mode to Cause and Effect,AQuA,FMEA Model,Six Sigma Champion Training,6,Linking Failure Mode to Cause and Effect,Man,Effect,Measurement,Materials,Environment,Machines,Methods,Failure Mode (Defect),Brainstorming Unstructured problem soling,Fishbone Model (5Ms & E),Six

5、 Sigma Champion Training,7,Man,Effect,Measurement,Materials,Environment,Machines,Methods,Prevent or detect,Goal of FMEA is to understand your process well enough to anticipate and prevent or detect the Failure Mode.,Prevent or Detect,Failure Mode Fishbone Model,Six Sigma Champion Training,8,FMEA For

6、m-Assessing Current Situation,Six Sigma Champion Training,9,FMEA Form-Assessing Current Situation,Six Sigma Champion Training,10,FMEA Form-Improvement Plan,Six Sigma Champion Training,11,Severity (SEV): How significant is the impact of the Effect to the customer (internal or external)? Occurrence (O

7、CC): How likely is the Cause of the Failure Mode to occur? Detection (DET): How Likely will the current system detect the Cause or Failure Mode if it occurs?,Ratings to Determine overall Risk,Each is Scored on a 1(Best) to 10 (Worst) Scale,A numerical calculation of the relative risk of a particular

8、 Failure Mode. Risk Priority Number (RPN) = SEV x OCC x DET This number is then used to place priority on which items need additional quality planning.,Risk Priority Number,RPN Directs the Improvement Effort,Six Sigma Champion Training,12,Standard Ratings,Six Sigma Champion Training,13,Steps in the

9、FMEA Process,1. Select the Process FMEA team 2. Develop a Process Map and identify all process steps 3. List all the Key Process Outputs (deliverables) to satisfy internal and external customer requirements 4. For each Process Step, list Key Process Inputs 5. Develop C&E matrix relating Product Outp

10、uts to Process Inputs 6. Rank the inputs according to importance,Six Sigma Champion Training,14,Note: When doing a Process FMEA, first assume the material is good, but the process is bad. Then assume the process is good, but the material is bad. Last, assume the process is unsafe.,Steps in the FMEA

11、Process,7. Start the process FMEA by listing ways that each process step can fail (Failure Modes) 8. For each Failure Mode, identify the Effects and Causes 9. Assign Severity, Occurrence and Detection rating to each Cause 10. Calculate the risk priority number for each potential failure mode 11. Det

12、ermine recommended actions to reduce all RPNs 12. Take appropriate actions 13. Re-calculate all RPNs,Six Sigma Champion Training,15,Cause and Effect Matrix Relating Customer Requirements to Process Inputs,Six Sigma Champion Training,16,Cause & Effect Matrix,This matrix provides the initial input to

13、the FMEA. When each of the Key Output Variables (Customer Requirements) are not correct, that represents potential ”Effects. When each Process Step/ Key Input Variable is not correct, that represents a ”Failure Mode. 1. List the Key Process Output Variables 2. Rate each Key Process Output Variable o

14、n a 1-to-10 scale to importance to the customer 3. List Process Steps/ Key Input Variables 4. Rate each Process Step/ Key Input Variable relationship to each Output Variable on a 1-to-10 scale 5. Select the top Process Steps or Key Input Variables based upon C&E Matrix Importance column to start the FMEA process,Six Sigma Champion Training,17,2. Rate each Output according to importance to customer,3. List Process Steps & Key Input Variables,4. Rate eac