Reliability Growth Planning using Retrofit or Engineering ChangeOrder-A Budget Based Decision Making

摘要

Two different corrective actions (CA) are often used for improving the reliability of in-service systems: retrofit andECO (engineering-change-order). Retrofit is a repair service that pro-actively replaces system modules orcomponents before they fail due to known failure modes. ECO is a counter-measure generally implemented in therepair center to fix and upgrade defective modules upon the failure return. This paper aims to evaluate the trade-offbetween the CA cost and the anticipated reliability growth in terms of the retrofit and ECO processes. We propose afix effectiveness function that is able to link the failure reduction rate with the amount of resources required toeliminate a particular failure mode. An optimization program is formulated to determine the best strategy of theresource allocation assuming system failures follow the Non-Homogenous Poisson (NHPP) process. The proposedidea benefits the reliability community in the sense that it provides a quantitative model for reliability practitionersor managers to make a sound decision to achieve the effective reliability growth using limited resources