SRC Forum - Message Replies

Forum: Reliability & Maintainability Questions and Answers

Topic: Reliability & Maintainability Questions and Answers

Topic Posted by: Reliability & Maintainability Forum (src_forum@alionscience.com )
Organization: System Reliability Center
Date Posted: Mon Aug 31 12:47:36 US/Eastern 1998

Original Message:

Posted by: Bob Fuerst (robert.fuerst@msfc.nasa.gov )
Organization:Hernandez Engineering
Date posted: Fri May 16 10:20:30 US/Eastern 2003
Subject: Failure rate for Multifiltration Bed
Message:
I am responsible for R&M analyses of a Water Processor Assembly that will be used aboard the International Space Station to process onboard waste water for crew consumption and O2 generation (via electrolysis). The WPA utilizes a number of multifiltration beds, ion exchange beds, and catalytic beds that are essentially tubes of packed media that absorb or catalyze contaminants in the process water stream. There has been a good bit of development testing & analyses that have been used to establish the expected wearout life of these items. However, this testing was insufficient to establish a random failure rate. I would like to know if there are any failure rate data sources for similar components, perhaps something similar is used aboard U.S. Navy ships or submarines. thanks in advance

Reply:

Subject: Reliability Filtration System
Reply Posted by: BWD (bdudley@alionscience.con )
Organization: RAC
Date Posted: Thu May 29 15:28:24 US/Eastern 2003
Message:
I researched our library for information related to this topic and could only find one piece of reliability data. From our Non-Electronic part database, a mechanical liquid filter in a ground fixed condition has a failure rate of 35 failures per billion hours. This could be used as a baseline with an adjustment of one half as defined in the Reliability Toolkit for conversion of ground to space data. This could be followed up with test or vendor data.