Impact of Ignored Faults on Reliability and Availability of Centrifuge System That Undergoes Periodic Rest

Abstract

The paper deals with a single unit centrifuge system that undergoes periodic rest wherein faults are classified as minor, ignored and major faults. The occurrence of a minor fault leads to degradation of the system whereas occurrence of a major fault leads to failure of the system. Ignored faults are the faults such as vibration, abnormal sound, etc that are ignored /delayed for repair during operation of the system until the system goes to rest or complete failure. However these faults may lead to failure of the system. The system undergoes periodic rest during rest period and upon complete failure of the system, the repairman first inspects whether the fault is repairable or non repairable and accordingly carries out repair or replacement of the system. Two repairman - an ordinary and other expert are considered. Various measures of system effectiveness such as mean sojourn times, mean time to system failure and steady-state availability of the system, are obtained using Markov processes and regenerative point technique. The conclusions regarding the reliability and availability of the system are drawn on the basis of the graphical studies.