Lifetime performance-qualified sampling system under a Weibull distribution with failure-censoring

Abstract

Reducing the warranty cost to increase profit is a major focus for most businesses. To achieve this goal, the acceptance sampling plan (ASP) can be an efficient tool to validate whether the product lifetimes meet their requirements. In the ASP practice, the single sampling plan (SSP) is widely used due to its administrative simplicity. Unfortunately, the SSP ignores the valuable sample information from preceding lots, which may reduce its efficiency and quality-discrimination power. Especially, the collection of lifetime information often consumes a significant amount of time and is expensive in today’s high product-yield and long-life environment. To address the drawbacks of the SSP, we propose a lifetime performance-qualified quick switch sampling (QSS) system under a Weibull distribution with failure-censoring. This system nimbly switches between the normal SSP and tightened SSP based on the previous lot-disposition result. Compared to the ordinary SSP and the recently proposed multiple-lot dependent sampling plan, the QSS system not only significantly reduces the required number of failures that need to be observed in the life testing but also exhibits a better discriminatory operating characteristic curve for the lot disposition. On the other hand, the QSS system helps the consumer to communicate to the supplier important messages that (i) only with reliable submissions the latter can persistently enjoy the benefits of the normal lot-sentencing standard; (ii) once the submitted lot is rejected, the supplier will have to spend more efforts to gain back the consumer trust. Moreover, we developed a web-based tool to help practitioners obtain the system criteria easily and quickly without the need for the traditional time-consuming table lookup. By operating the interactive interface of the web app, practitioners can quickly obtain the system criteria conforming to the requirements. Finally, the proposed QSS system is illustrated by a real-life application.