Citation

Thomas HM. Reliab. Eng. 1981; 2(2): 83-124.

Copyright

(Copyright © 1981, Elsevier Publishing)

DOI

10.1016/0143-8174(81)90017-2

PMID

unavailable

Abstract

This generalised approach to the estimation of failure probability is based on a pragmatic and scientific analysis of actual service failure statistics. Approximation strategies have been devised in order to estimate failure probability at the leakage level PL and for rupture PC.

PL is estimated from global statistics for leakage failure by using an observed correlation that a geometric proportionality measure of size and shape and weldments gives a direct measure of failure probability. This is the most powerful single influence of all in the determination of PL, but the influence of plant age is also worth considering. The estimate may then be scaled for other factors if their influence is known.

PC may be estimated given a PL estimate, partly by using a fracture mechanics model which gives a carpet of PC/PL curves. Observed statistics are also used.