SRC Forum - Message Replies
Forum: Reliability & Maintainability Questions and Answers
Topic: Reliability & Maintainability Questions and Answers
Topic Posted by: Reliability & Maintainability Forum
Organization: System Reliability Center
Date Posted: Mon Aug 31 12:47:36 US/Eastern 1998
Posted by: P. Kamaleshwara Rao
Organization:Centre For Reliability
Date posted: Thu Jun 20 2:48:17 US/Eastern 2002
Subject: Accelerated Test/ Life Test/ Reliability Test
We want to test a Filter to have a life of 40 years at
50 degree celcius & 90 percent humidity. This filter is used
in compressed air applications.This filter removes moisture
and particulate matter from the air.This is a simple passive
Please suggest whether Accelerated test can be conducted on
this ? If so what are the accelerated conditions and how
to extrapolate the data.If accelerated test is not possible
can we do Reliability Demonstration test? If so hoh to go about it?
Thanks in advance.
Subject: Filter Test
Reply Posted by: B.W.Dudley
Date Posted: Thu Jun 20 11:06:37 US/Eastern 2002
The requirement for a filter to last 40 years is extraordinarily long in duration for an item that essentially is a passive collector of particles. The life of the item is really a function of the size of the particle and the rate that they are encountered. Therefore, if one tests at a higher rate and size of particle, you should be able to determine the collection efficiency. This information could be extrapolated to show life time efficiency at lower particle rates. My suggestion is to test a large number of filters, say 20 or30, in ten or more different particle rates and sizes. Statistical evaluations of the percentage of contamination could be used as a design of experiments to determine the weaknesses and possible the life of the filter.
Reliability tests do not seem to be applicable to your requirement. This requirement is an end of life value not the random failure event that reliability tests are design to evaluate.
Thank you for your interest in the Reliability Analysis Center.