|
|
| (One intermediate revision by the same user not shown) |
| Line 1: |
Line 1: |
| {{Reference Example}} | | {{Reference Example}} |
|
| |
|
| This example compares the warranty data analysis results. | | This example validates the results of a warranty data analysis in a Weibull++ warranty folio. |
|
| |
|
|
| |
|
| Line 127: |
Line 127: |
|
| |
|
|
| |
|
| The following picture shows the parameters of the lognormal distribution and the converted failure/suspension data. The results are the same as the results shown in the book. | | The following picture shows the parameters of the lognormal distribution and its associated failure/suspension data. The results are the same as the results shown in the book. |
|
| |
|
| [[Image: warranty_results.png|center]] | | [[Image: warranty_results.png|center]] |
| | |
| | |
| | The following picture shows the probability plot of the lognormal distribution. |
| | |
| | |
| | [[Image: warranty_plot.png|center|550 px]] |
Latest revision as of 16:24, 28 September 2015
New format available! This reference is now available in a new format that offers faster page load, improved display for calculations and images and more targeted search.
As of January 2024, this Reliawiki page will not continue to be updated. Please update all links and bookmarks to the latest references at Weibull examples and Weibull reference examples.
|
Warranty Data Analysis Example
|
This example validates the results of a warranty data analysis in a Weibull++ warranty folio.
Reference Case
The data set is from Example 11.2 on page 453 in the book Life Cycle Reliability Engineering by Dr. Guangbin Yang, John Wiley & Sons, 2007.
Data
A Nevada chart for the warranty data is provided in Table 11.3. The last two rows were combined, as specified in the example.
|
|
TTF
|
| TIS
|
1
|
2
|
3
|
4
|
5
|
6
|
7
|
8
|
9
|
10
|
11
|
12
|
Total
|
Sales Volume
|
|
|
| 12
|
3 |
0 |
3 |
3 |
4 |
2 |
1 |
5 |
4 |
2 |
3 |
3 |
45 |
2123
|
| 11
|
0 |
1 |
2 |
0 |
4 |
2 |
1 |
2 |
0 |
4 |
3 |
|
30 |
1853
|
| 10
|
1 |
3 |
2 |
2 |
3 |
4 |
3 |
5 |
4 |
8 |
|
|
45 |
2238
|
| 9
|
1 |
2 |
0 |
3 |
4 |
2 |
2 |
3 |
6 |
|
|
|
32 |
3052
|
| 8
|
2 |
3 |
2 |
6 |
2 |
1 |
6 |
4 |
|
|
|
|
34 |
2953
|
| 7
|
1 |
1 |
3 |
2 |
1 |
4 |
8 |
|
|
|
|
|
27 |
2788
|
| 6
|
1 |
0 |
1 |
0 |
1 |
2 |
|
|
|
|
|
|
11 |
2037
|
| 5
|
0 |
0 |
1 |
1 |
0 |
|
|
|
|
|
|
|
7 |
1863
|
| 4
|
0 |
0 |
1 |
1 |
|
|
|
|
|
|
|
|
6 |
1231
|
| 3
|
0 |
1 |
1 |
|
|
|
|
|
|
|
|
|
5 |
823
|
| 2
|
0 |
1 |
|
|
|
|
|
|
|
|
|
|
3 |
638
|
| 1
|
0 |
|
|
|
|
|
|
|
|
|
|
|
1 |
568
|
|
|
| Total
|
9 |
12 |
16 |
18 |
19 |
17 |
21 |
19 |
14 |
14 |
6 |
3 |
|
Result
The book first converted the data in the table above into the following format, as given in Table 11.4 in the book.
| TTF (Months)
|
Number of Failures
|
Number of Censored Units
|
| 1 |
9 |
568
|
| 2 |
12 |
637
|
| 3 |
16 |
821
|
| 4 |
18 |
1229
|
| 5 |
19 |
1861
|
| 6 |
17 |
2032
|
| 7 |
21 |
2768
|
| 8 |
19 |
2927
|
| 9 |
14 |
3029
|
| 10 |
14 |
2203
|
| 11 |
6 |
1834
|
| 12 |
3 |
2090
|
A lognormal distribution is used and the fitted model parameters are: Ln-Mean = 6.03 and Ln-Std = 1.63.
Results in Weibull++
In Weibull++, the data set is entered into a warranty folio, using the Nevada chart format. The following pictures show the sales and returns data.
The following picture shows the parameters of the lognormal distribution and its associated failure/suspension data. The results are the same as the results shown in the book.
The following picture shows the probability plot of the lognormal distribution.
