Component replacement and the use of Relcode

Abstract The paper reviews briefly the standard age and block replacement models for setting component replacement rules, highlighting the importance of correct identification of the failure distribution of the component. The main focus of the paper is on procedures for identification of the failure distribution. Three procedures are covered: 1. (i) classical statistical distribution fitting 2. (ii) use of probability paper (particularly Weibull) to estimate the parameters of the failure distribution 3. (iii) use of a computer package Relcode Of the above procedures emphasis is on use of the Relcode computer software package which is used for the analysis of data relating to the failures and successful performance of machines or components. The analyses range from simple calculations such as mean life, to the fitting of the Weibull and other distribution models, and renewal and planned replacement analyses. Relcode may use data arising from reliability trials or from other day-to-day records of failure and successful performance of the items concerned. The package allows for the possibility of multiply censored data, that is items (called suspended items) which perform successfully without failure—as well as for items which fail.