6a学习教材

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Design for Six Sigma
What is Error Proofing?
Also denoted as Fool proofing, Poka-Yoke, mistakeproofing, etc. * * * * * Error proofing the design and the production process Strives for zero defects Leads to Quality Inspection Elimination Respects the intelligence of workers Minimizes tasks that rely on memory
Safeguards: Attentiveness, discipline, work standardization.
7. Errors due to slowness: Sometimes we make mistakes when our actions are slowed down by delays in judgement. For example, a person learning to drive is slow to step on the brake.
Safeguards: Work standardization, work instructions.
9. Surprise errors: Errors sometimes occur when equipment runs differently than expected. For example, a machine might malfunction without warning.
Error Proofing
Francis Xu May 10, 02
Acknowledgment: Special thanks for the majority of the training material from HS Yam of Seagate
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Safeguards: Training, attentiveness, vigilance.
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Design for Six Sigma
The Different Kinds of Errors (cont.)
4. Errors made by amateurs: Sometimes we make mistakes through lack of experience. For example, a new worker does not know the operation or is just barely familiar with it.
Why do Error Proofing?
Quality and Stability is essential in a lean manufacturing environment
• Human error is a natural occurrence; all humans make errors • Machines are not defect-free
Safeguards: Skill building, work standardization.
5. Willful errors: Sometimes errors occur when we decide that we can ignore rules under certain circumstances. For example, crossing a street against a red light because there are no cars in sight at the moment.
– prevention of personal injury – promotion of job safety – prevention of faulty products or service – prevention of machine damage
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Safeguards: Skill building, work standardization. © Optimal, Confidential
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Design for Six Sigma
The Different Kinds of Errors (cont.)
8. Errors due to lack of standards: Some errors occur when there are no suitable instructions or work standards. For example, a measurement may be left to an individual worker’s discretion.
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Design for Six Sigma
What are the Benefits?
• Enforces operational procedures or sequences, thus insuring quality • Signals or stops a process if an error occurs or a defect is created • Eliminates choices leading to incorrect actions • Prevents product damage • Prevents machine damage • Prevents personal injury • Eliminate inadvertent mistakes which increase work load
Safeguards: Basic education and experience.
6. Inadvertent errors: Sometimes we are absentminded and make mistakes without knowing how they happened. For example, someone lost in thought tries to cross the street without even noticing that the light is red.
Safeguards: Total productive maintenance, work standardization.
10. Intentional errors: Some people make mistakes deliberately. Crimes and sabotage are examples.
1. Forgetfulness: Sometimes we forget things when we are not concentrating. For example, the stationmaster forgets to lower the crossing gate.
Safeguards: Alerting operator in advance or checking at regular intervals.
Safeguards: Training, checking in advance, standardizing work procedures.
3. Errors in identification: Sometimes we misjudge a situation because we view it too quickly or are too far away to see it clearly. For example, a $1 bill is mistaken for a $10 bill.
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Design for Six Sigma
Elevator Speech Disaster
I didn’t mean to press the alarm!!!
4 1
5 2
Alarm
6 3
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Design for Six Sigma
Process Flow ERROR To Next Process
POSSIBLE DEFECT
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Design for Six Sigma
The Different Kinds of Errors
Almost all defects are caused by human errors. However, there are at least ten kinds of human errors.
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Design for Six Sigma
An VBA example
On Error Resume Next ' Defer error handling. Error 11 ' Simulate the "Division by zero" error. • This example uses the Error statement to simulate error number 11.
2. Errors due to misunderstanding: Sometimes we make mistakes when we jump to the wrong conclusion before we’re familiar with the situation. For example, a person not used to a car with automatic transmission steps on the brake, thinking it is the clutch.