Estimation of machine setup and changeover times by survival analysis

• Published in: Computers & industrial engineering 2021-03, Vol.153, p.107026, Article 107026
• Main Authors: Ruppert, Tamas, Csalodi, Robert, Abonyi, Janos
• Format: Article
• Language: English
• Subjects: Changeover; Cox regression; Manufacturing; Operator support; Performance management; SMED projects; Survival analysis
• ISSN: 0360-8352; 1879-0550
• DOI: 10.1016/j.cie.2020.107026

•Survival analysis models provide accurate prediction changeover times.•The Cox regression models can handle product- and operator-dependent losses.•The models consider the stochastic nature of the work of the operators.•The interpretable models can support the identification the root causes of the losses.•The applicability of the method is demonstrated in the setups of cutting machines. The losses associated with changeovers are becoming more significant in manufacturing due to the high variance of products and requirements for just-in-time production. The study is based on the single minute exchange of die (SMED) philosophy, which aims to reduce changeover times. We introduced a method for the analysis of these losses based on models that estimate the product- and operator-dependent changeover times using survival analysis. The root causes of the losses are identified by significance tests of the utilized Cox regression models. The resulting models can be used to design a performance management system that considers the stochastic nature of the work of the operators. An anonymized manufacturing example related to the setup of crimping and wire cutting machines demonstrates the applicability of the method.