Optimal preventive maintenance level for a repairable product under warranty subject to multimode failure process

Abstract

PurposeThe purpose of this paper is to develop a model that determines whether how much effort of preventive maintenance action is worthwhile for the consumer over the post-sale product life cycle of a repairable complex product where the product is under warranty and subject to stochastic multimode failure process, that is, damaging failure and light failure with different probabilities.Design/methodology/approachThe expected life cycle cost is designed for a warranted product from the consumer perspective. The product failure is quantified with failure rate function, which is the number of failures incurred over the product life cycle. The authors consider the failure rate function reduction method in their model where the scale parameter of a failure rate function is maximized by applying the optimal preventive maintenance level. The scale parameter of any failure distribution refers to the meantime to failure (MTTF). The first-order condition is applied with respect to the maintenance level in order to achieve the convexity of the nonlinear function of the expected life cycle cost function.FindingsThe authors have found analytically the close form of the preventive maintenance level, which can be used to find the optimal reduced form of the failure rate function of the product and the minimum product expected life cycle cost under the given condition of multimode stochastic failure process. The authors have suggested different maintenance policies to consumers in order to implement the proposed preventive maintenance model under different conditions. A numerical example further illustrated the analytical model by considering the Weibull distribution.Practical implicationsThe consumer may use this study in the accurate modeling of the life cycle cost of a product that is under warranty and fails with a multimode failure process. Also, the suggested preventive maintenance approach of this study helps the consumer in making appropriate maintenance decisions such as to minimize the expected life cycle cost of a product.Originality/valueThis study proposes an accurate estimation of a life cycle cost for a product that is under the support of warranty and fails with multimode. Furthermore, for such a kind of product, which is under warranty and fails with multimode, this study suggests a new preventive maintenance approach that assures the minimum expected life cycle cost.

A decision support system to evaluate the quality and warranty policies for remanufactured products

“…Remanufacturing markets have been rapidly expanding in recent years (Alqahtani and Gupta, 2017;Gong et al, 2020;Grigg, 2021). There are different types of remanufactured products that are now being produced with full or partial-reused, rebuilt, and recycled components and/or modules (Sakao and Sundin, 2018;Shao et al, 2019;Steeneck and Sarin, 2017;Changa, 2021;Ullah et al, 2021;Ben Mabrouk and Chelbi, 2022). To have a better understanding of product recovery with a closed loop system, Figure 1 shows that in practice, there are four alternative dispositions to be considered for waste reduction, such as maximising those components and/or parts reuse, rebuild and recycle and reducing some components and/or parts to be disposed for landfills as discussed in some prior studies (Johnson and McCarthy, 2014;Kwak and Kim, 2015).…”

“…The increased consumption of increasingly scarce raw materials is still one of the main concerns for manufacturers (Zarte et al, 2019;Shao et al, 2019;Grigg, 2021). As a manufacturer's cost-savings strategy, the integration of remanufacturing practices in supply chain has proven to address this issue by reducing waste and minimising production costs (Abu Ghazaleh et al, 2019;Ullah et al, 2021;Liao et al, 2015;Chattopadhyay and Murthy, 2000). Fundamentally, remanufacturing is the process of returning a used product to its original performance (Alqahtani and Gupta, 2017;Gong et al, 2020;Grigg, 2021).…”

“…In practice, warranty coverage can be used as the marketing strategy for the sales of remanufactured products (Alqahtani and Gupta, 2017), reducing a customer's sense of risk. For the business model to function, manufacturers need to understand the total cost associated with upgrades and servicing time that should be lower than overall warranty servicing costs incurred (Abu Ghazaleh et al, 2019;Ullah et al, 2021). In the case of remanufactured product's failure, a manufacturer must replace at either no or a fraction of the replacement cost and/or alternatively refund full or part of the sales price to the buyer as per terms and conditions of the warranty contract (Abu Ghazaleh et al, 2019;Ullah et al, 2021).…”

“…For the business model to function, manufacturers need to understand the total cost associated with upgrades and servicing time that should be lower than overall warranty servicing costs incurred (Abu Ghazaleh et al, 2019;Ullah et al, 2021). In the case of remanufactured product's failure, a manufacturer must replace at either no or a fraction of the replacement cost and/or alternatively refund full or part of the sales price to the buyer as per terms and conditions of the warranty contract (Abu Ghazaleh et al, 2019;Ullah et al, 2021). Failure to do so can result in loss, as opposed to profit, in pursuit of the sale of remanufactured products.…”

“…In addition to that, it is also primarily due to the uncertainties of useful life, consumer usage patterns and cost of rectifications over a period of time (Khor and Hazen, 2017;Liao et al, 2015). Manufacturers are understandably interested in developing an effective way of monitoring and collecting the failure data and developing an optimisation model for the warranty analysis via a collaborative decision support system (DSS) as discussed in prior studies (Changa, 2021;Ullah et al, 2021;Alkahtani et al, 2019). This study proposes the warranty servicing policies that can be introduced by manufacturers, and offers a comparison of the profits arising from different types of warranties in DSS.…”