Forum: Reliability & Maintainability Questions and Answers
Posted by: Priya shelton
Date posted: Tue May 20 9:26:54 US/Eastern 2003
Subject: Software FMEA
Hello All, What is Software FMEA? Is there any Guideline/Standard for performing the same. Thanks
Posted by: Bob Fuerst (firstname.lastname@example.org )
Date posted: Fri May 16 10:20:30 US/Eastern 2003
Subject: Failure rate for Multifiltration Bed
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
Posted by: Bob Valerius (email@example.com )
Organization:Northrop-Grumman Oceanic & Naval Systems
Date posted: Thu May 8 11:28:56 US/Eastern 2003
Subject: One-Shot Device Reliability Analysis
Is there any way to do an analysis or prediction on a one shot device? I realize that the binomial theoreum can be used to estimate reliability at a specified confidence level if you have test data. However, we are trying to build an undersea (depth = 1200 feet) cable cutter (has electronics and hydraulics) that sits for as many as 30 days and then is exercised. Thus multiple real life tests of this would be extremely long and expensive. Also, any ideas on how we could acclerate the test time? Thanks in advance. Bob Valerius
Posted by: Brandon
Date posted: Thu May 8 4:09:30 US/Eastern 2003
Subject: Can HASS replace ESS??
I wonder whether HASS can replace ESS? Under what condition(s) we cannot apply HASS? Also, is there any restriction in carrying out HASS? Can HASS be carried out for SRUs? Thank you.
Posted by: Brandon
Date posted: Thu May 8 4:05:41 US/Eastern 2003
Subject: Realistic Quality Factor for Reliability Prediction of Commercial Components
I am currently carrying out a reliability prediction for a military equipment that uses commercial components. I'm using Parts Stress Analysis. According to MIL-HDBK 217F, the "Pie Q" for these commercial components is above "1". This may be true more than 10 years ago, when 217F is being written, but is it still true now? Please advise. What is a more realistic "Pie Q" that I should use now? Can it be as low as "1"? Thank you for your help.