ACME Example

ACME manufacturing has implemented an accelerated testing program for their new design. A total of 40 units were tested at four different pressure levels. The operating stress level is 170psi.

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Do the following:

Determine the parameters of the inverse power law weibull model.
Obtain the use level probability plot with 90% 2-sided confidence bounds on time.
Obtain the life vs. stress plot with 90% 2-sided confidence bounds.

Solution to Example 6: Acme Example

The parameters of the IPL-Weibull model are estimated to be,

β = 3.009236
K = 3.267923E – 27,
N = 10.218104.

The use level probability plot is shown next.

The confidence bounds on time are the Type 1 bounds (time bounds) in ALTA.

Similarly, the life vs. stress plot with the confidence bounds can be obtained.