Pi_part_manufacturing and Pi-induced factors

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Pi_part_manufacturing and Pi-induced factors
In the FIDES guide (page 32), the data entry are:
* Environments and uses condtions of the product
* Definition of the product
* Life cycle of the product
* Suppliers of the articles used in the product

My question is : is it obligatory to get these four data entry to calculate the failure rate of a component or the first two data are sufficient ?

Other subject :
My 2nd question is : which is the influence of "Pi_part_manufacturing" factor on the whole failure rate ? Because I don′t see his role ?
My 3rd quastion is : The Pi_application and Pi_hardening factors, are they datas which customer should give me ?

Re: Pi_part_manufacturing and Pi-induced factors

Hi samiceau,

- Environments (life profile) and definition of the product are not optionnal for the prevision. This datas are used for the evaluation of the lambda_0, the Pi_acceleration, the Pi_induced.

- The life cycle of the product has to be assessed through the reliability audit for the evaluation of the Pi_process factor. The interest of this audit shall not be minimized. But a preliminary reliability assessment may be done with the default value.

- The quality and reliability practices of the suppliers are needed for the evaluation of the Pi_Part_manufacturing factor. Again, this factor is a usefull tool for suppliers selection. But a preliminary assessment may be done with the default values proposed in the FIDES Guide. This factor goes from a value of 0.5 (the best supplier will lead to half less failures) to 2 (the worse will lead to twice more failures).

- The pi_application is one element of the life profile (new name of the mission profile). It shall be defined with the life profile. The most of the mission profile shall be defined by the customer. But it is not always fully the case. It′s a hard job to be a reliability engineer (don′t do this job!).

- The Pi_hardening factor is a process factor and has to be estimated by the supplier of the product.