Warranty cost analysis: quasi‐renewal inter‐repair times

Abstract

Purpose

To provide a brief introduction to warranty analysis and a classification of general repairs. To introduce the notion of accelerated probability distribution and use it to model imperfect warranty repairs.

Design/methodology/approach

The notion of accelerated probability distribution is discussed and its similarity with quasi‐renewal and geometric processes is observed. An approach to modeling imperfect warranty repairs based on the accelerated probability distributions is presented, and the corresponding expected warranty cost over the warranty period under non‐renewing free replacement warranty policy is evaluated.

Findings

It is observed that quasi‐renewal and the geometric processes are equivalent. Using data from an existing warranty database it is shown that the inter‐repair times form a quasi‐renewal process. The corresponding expected warranty cost over the warranty period under a non‐renewing free replacement warranty policy is evaluated.

Research limitations/implications

This approach is applicable only if the cost of the warranty repair is an increasing function of the number of repairs.

Practical implications

Provides a useful approach to modeling inter‐repair times incorporating the idea of imperfect repairs in practice.

Originality/value

Provides an approach to model imperfect warranty repairs and to evaluate the corresponding expected warranty cost.

Citation

Chukova, S. and Hayakawa, Y. (2005), "Warranty cost analysis: quasi‐renewal inter‐repair times", International Journal of Quality & Reliability Management, Vol. 22 No. 7, pp. 687-698. https://doi.org/10.1108/02656710510610839