Abstract A continuous improvement of Stirling integral coolers MTTF is necessary to answer the new market requirements. The time spent in the design phase is critical to get the product ready at the right time and to reduce the development costs. In order to reduce the development risks (be sure to get in the new design at a higher MTTF), we have developed a calculation method for prediction of the expected MTTF of our coolers. Early in the design phase, we use the method of predictive calculations on MTTF. For that, we need MTTF data for each critical single part or function in the cooler. In order to fill the lack of data available on failure rates for mechanical parts (tightness, coating...) in our particular application, we built a list of the different functions inside the cooler from the failure point of view. The data collected from the extensive lifetest results already performed allow us to determine the MTTF for each function. These elements are introduced into the predictive calculation of the new design. The expected MTTF of the new cooler is then available. The results obtained by calculation are still only indicative. These results have to be verified as quickly as possible. To reduce the duration of lifetests, we apply an accelerated test procedure developed and verified over 2 years. This method allows us to obtain results on MTTF equivalent to several thousand hours using only a test duration of a few weeks. This method has been validated on previous cooler models. This MTTF calculation is today applied to all designs of our integral coolers, and in particular, to our new design of the RM2 cooler under development at Thales Cryogenics. This method will be discussed and the results of the calculations performed on the new RM2 design will be presented.
MTTF Prediction in Design Phase on Thales Cryogenics Integral Coolers
Cryocoolers 12 ; 87-94
2002-01-01
8 pages
Article/Chapter (Book)
Electronic Resource
English
MTTF Prediction in Design Phase on Thales Cryogenics Integral Coolers
British Library Conference Proceedings | 2003
|Online Contents | 2007
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Elsevier | 1983
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