Читать книгу System Reliability Theory - Marvin Rausand - Страница 144

It is important to realize that a failure mode is a manifestation of the failure as seen from the outside, that is, the nonfulfillment of one or more functions. “Internal leakage” is thus a failure mode of a shutdown valve because the valve loses its required function to “close flow,” whereas wear of the valve seal represents a cause of failure and is hence not a failure mode of the valve.

Failures and failure modes may be classified according to many different criteria. We briefly mention some of these classifications.