Your Reliability Engineering Professional Development Site
There are two common uses for a check sheet. First, to summarize historical data, or second, to collect observations. A byproduct of creating a check sheet is team agreement on definitions of categories and observation procedures.
The investment is minimal other than thinking about how you want to view the data, and what data to collect. [Read more…]
Reliability testing and data collection is a messy business.
We rarely receive perfect data where all units involved have a precise time to failure record. Sometimes we do not the precise time to failure information or some of the units are still operating.
The data is censored.
There are a few common types of censoring, each of which has statistical techniques to appropriately account for the unknown elements. [Read more…]
The Failure Reporting and Corrective Action System (FRACAS) is a closed-loop process whose purpose is to provide a systematic way to report, organize and analyze failure data. Implementation of a FRACAS has increasingly become commonplace within an industry. The requirement for implementation of some type of FRACAS within a DoD program was first established in 1985 with MIL-STD-2155. However, in 1995 that standard was reestablished with no changes to content as a handbook, MIL-HDBK-2155, and was recommended as guidance. Today, multiple software solutions exist that provide all the functionality required of a FRACAS. [Read more…]
Just a couple of sample questions from deep in the body of knowledge this week.
Which of the following can be evaluated with dye penetrant methods? [Read more…]
First the Question:
Fred,
Early in the FMEA lecture you worked through a homework problem and you mentioned that a cdf may not be linear (hence the reason for giving three points in a reliability goal). Can you give an example of two of things you’ve seen with non-linear cdf’s? I’ve only done limited reliability testing at this point, but everything I’ve done and every example I’ve ever seen have had linear cdf’s.
Thanks,
John
And, my response: [Read more…]
EAM & CMMS Systems, 10 times more data in the system or 10 time less done with the data available?.
A nice short article about the problem of data, data, too much data.