Chapter 6 (SCM 488)
1. There are 6 key aspects to Total Quality Management. What are they?
2. What is ISO 9001?
3. Cost of Quality (CoQ) can be broken up into 4 costs. List them and describe each.
4. Describe what is meant by the economic conformance point.
5. A medical company produces a part that has a hole measuring 0.5" + 0.050" (i.e. maximum tolerance is 0.55"). The tooling used to make the hole is worn and needs replacing, but management doesn't feel it necessary since it still makes "good parts". All parts pass QC, but several parts have been rejected by assembly. Failure costs per part is $45.00. Using the Taguchi loss function, what is the average loss per part?
Measured Values
0.459 | 0.478 | 0.495 | 0.501 | 0.511 | 0.527
0.462 | 0.483 | 0.495 | 0.501 | 0.516 | 0.532
6. A process engineer was producing parts on a new machine and wanted to know the upper control limit (UCL) and lower control limit (LCL) of her process relative to the 11mm to 15mm product tolerance range. She measured parts over a 6 day period. Each day a group of 9 pieces was measured (mean values listed below). Across all 54 pieces measured (i.e. 9 pieces per group and 6 groups) standard deviation (??) was 1. Using X bar charting, what are the UCL and LCL? Is this process capable of meeting product tolerances?
|
Day
|
Mean
|
|
1
|
10
|
|
2
|
15
|
|
3
|
14
|
|
4
|
13
|
|
5
|
11
|
|
6
|
12
|
7. A customer requires <6 mm dispersion of process as a requirement for manufacturers. Theengineer intends to use R bar charting to show this capability. Across 6 groups she collects 3 pieces per group. Do the R bar UCL and LCL show this process is capable?
|
3 samples per group
|
Subgroup
|
|
x1
|
x2
|
x3
|
Range
|
|
1
|
10
|
11
|
11
|
1
|
|
2
|
12
|
12
|
13
|
1
|
|
3
|
13
|
14
|
12
|
2
|
|
4
|
13
|
14
|
12
|
2
|
|
5
|
15
|
12
|
14
|
3
|
|
6
|
13
|
12
|
11
|
2
|
8. A manager would like to determine if 100% inspection is required or not. The amount of defects inspectors are finding is 1%. The cost of poor quality (i.e. customer returns, scrap, etc.) is $10 per part made. The inspection cost is $0.5 per part. Based on break even analysis, should the manager be using 100% inspection?
9. Parts are being made in 1,000 piece batches. A producer and consumer contractually agree on Acceptable Quality Limit (AQL) plan based on ISO 2859 standard inspection level II of 2.5% for major defects. In order for the manager to staff his inspection department, he needs to know inspection lot sizes. What is the inspection lot size? If rejects found are 9, should the lot be rejected?
