To complete this assignment successfully, you should:
Assignment – Statistical Process
Control
1. The overall average on a process you are attempting to monitor is 50 units. The average range is 4 units. What are the upper and lower control limits if you choose to use a sample size of 5?
2. Sampling 4 pieces of precision-cut wire (to be used in computer assembly) every hour for the past 24 hours has produced the following results. Develop appropriate control charts and determine whether there is any cause for concern in the cutting process.
|
Hour |
R |
|
|
1 |
3.25 |
0.71 |
|
2 |
3.10 |
1.18 |
|
3 |
3.22 |
1.43 |
|
4 |
3.39 |
1.26 |
|
5 |
3.07 |
1.17 |
|
6 |
2.86 |
0.32 |
|
7 |
3.05 |
0.53 |
|
8 |
2.65 |
1.13 |
|
9 |
3.02 |
0.71 |
|
10 |
2.85 |
1.33 |
|
11 |
2.83 |
1.17 |
|
12 |
2.97 |
0.40 |
|
13 |
3.11 |
0.85 |
|
14 |
2.83 |
1.31 |
|
15 |
3.12 |
1.06 |
|
16 |
2.84 |
0.50 |
|
17 |
2.86 |
1.43 |
|
18 |
2.74 |
1.29 |
|
19 |
3.41 |
1.61 |
|
20 |
2.89 |
1.09 |
|
21 |
2.65 |
1.08 |
|
22 |
3.28 |
0.46 |
|
23 |
2.94 |
1.58 |
24 |
2.64 |
1.97 |
|
3.
Daily
samples of 100 power drills are removed from Drill Master’s assembly line
and inspected for defects. Over
the past 21 days, the following information has been gathered. Develop a 3 standard deviation (99.7% confidence) p-chart and graph the samples. Is the process in control?
Day
|
Number of
Defective Drills |
1
|
6
|
2
|
5
|
3
|
6
|
4
|
4
|
5
|
3
|
6
|
4
|
7
|
5
|
8
|
3
|
9
|
6
|
10
|
3
|
11
|
7
|
12
|
5
|
13
|
4
|
14
|
3
|
15
|
4
|
16
|
5
|
17
|
6
|
18
|
5
|
19
|
4
|
20
|
3
|
21
|
7
|
Go on to Statistical
Process Control- Self Test Look
here
before beginning quiz if using a telephone modem.
or
Go back to Statistical
Process Control: Activities and Assignments
Please reference "BA501 (your last name) Assignment name and number" in the subject line of either below.
E-mail Dr. Rakesh Pangasa at
BA501@mail.cba.nau.edu
or call (928) 344-7588. Use WebMail for attachments.
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Arizona University
ALL RIGHTS RESERVED