Reduction of the All‐Time Requirement for Spare Parts Available to Purchase

An industry which manufactures and sells products that are liable to failure (e.g. TV sets, tape recorders, washing machines or refrigerators), usually has a department for “service after‐sales”. Such a department must distribute information on how to repair products, and also supply spare parts to replace defective components during a given number of years. We call these spare parts service parts. Three phases can be distinguished in the life‐cycle of service parts: the initial, the repeat, and the final phase.