STM Journals Peer-reviewed research from Consortium e-Learning Network

Journal of Production Research & Management

Parallel Conwip for a High-mix Multi-stage Production System with the entrance of rework

  1. Joshua Prakash
  2. Chong Mei Yong
  3. Shaliza Azreen Mustafa
  4. Chin Jeng Feng

Abstract

In a complex production environment, more than one type of pull systems is often used to regulate the processesof different products. In literature, performance studies appertaining to multiple pull systems co-existed in aproduction environment are rare. The present paper evaluates the performances of parallel CONWIP (PC)systems in a high-mix production system with the entrance of rework. The production comprises three stages ofshared-machine facilities. Reject parts produced by the first stage are to be reworked by an independent stationand later readmitted into the middle stage to undergo the remaining processes. The high- and low-runnerproducts are handled using a separate CONWIP system. The PC systems were differentiated in terms of themodel driver, loading rule, and rework entrance policy. The performance measures adopted are total output,average work-in-process, flow times, and average machine utilizations. Discrete-event simulations wereconducted with an analysis enhanced by multi-factor ANOVA and response surface methodology. From theanalysis, the major finding is that optimum performances can be achieved at a specific composition of low- andhigh-runner products when low-runner products are loaded first at all stages. The merging of the reworkedparts with a forthcoming similar batch is consistently superior to its counterparts.

Keywords

Support