FIXING RELIABILITY TARGET

[Senthil Kumar. R]

Hai,

Can anyone please explain me the steps to fix the Target for Reliability using engineering methods & also how to find out the Reliability of a product in the design state itself.

[Tarik]

Hi,
The reliability goal has to be determined by the product managers.
Usually this goal is determined through a warranty replacement goal (for example, mangers can determine that no more than 10% of products can fail after 2 years of use), or it could be imposed by the customer (government projects for example) or specified by some industry standards, or to meet a certain competitive goal (for example, competition advertise that their products have an MTBF of 5000hours, so you decide that your product needs to have an MTBF of 5500hours)

After determining the reliability goal, the question that remains is how to allocate or distribute the reliability goal throughout the components of the system. Reliasoft’s BlockSim provides a tool that optimizes the reliability allocation throughout the system considering the cost/difficulty of increasing reliability. With this tool you can determine what each part/component of the system’s reliability will need to be to meet the overall reliability goal.
http://www.weibull.com/SystemRelWeb/improving_reliability.htm

RGA provides the capability to monitor the reliability improvement during the developmental due to changes in product design or the manufacturing process. Please review the following resources:
http://www.reliasoft.org/pubs/rga6_brochure.pdf

[Weibull.nl]

Tarik and Kumar,
I srongly believe that a Reliability target is "set" by our customers, and not by managers. The best a manager can do is try to translate the custimers requirements to engineering reliability targets. Within many companies, not the manager, but a dedicated Reliability Engineer sets proper Engineering targets. Further for Systems, apart from the overall system target, seperate targets for the components in the system have to be set! Thus each engineer knows where to develop for. BlockSim will help with this, the moment you have systems with redundancy in it. If not, a simple list will do the trick pretty good as well, and is much easier to explain to both engineer and managers.
Measuring system reliability growth can be done with Crow-AMSAA. Component reliability growth normally is monitoren with Weibayes or Weibull analysis.

[usara_reliable]

You have to fix the target with your constraints depend on the customer need. You cann't design infinite life as customer wann but u look with as much possible with ur limit.

I think you know the remian detail.