USING SIMULATION TO EVALUATE THE INTRODUCTION OF A KANBAN SUBSYSTEM WITHIN AN MRP-CONTROLLED MANUFACTURING ENVIRONMENT

A large assembly plant of parts for the automotive industry uses an MR P system for the mid-term planning and has developed some finite-capac ity scheduling software for the scheduling of the final assembly step of its products. This software uses a heuristic which tries to respect due dates and to minimise production costs, which consist mainly of s et-ups. One of the problems with this software is that it does not tak e the availability of subparts into consideration. In fact, the produc tion of subparts must also deal with the problem of set-up minimisatio n. The difficulty lies in the fact that the technical parameters that determine ''a good sequence'' differ for each production step. At the moment, human planners spend a lot of time and effort to coordinate an d fine tune the production sequences in the various production and ass embly steps. There are plans to produce some subparts of the product i n a Kanban-controlled manner. A simulation model is described which al lows to study the feasibility of these plans and to determine the oper ational parameters (such as number of Kanbans and container size). Thi s feasibility study was carried out for two scenarios: (1) all subpart types are produced in a Kanban controlled manner and (2) only the pro duction of fast-movers on two (out of three) machines is Kanban contro lled. The sensitivy of the results vis-a-vis a number of assumptions ( set-up time reduction, machine breakdowns, tool availability, etc.) is also presented. (C) 1998 Elsevier Science B.V. All rights reserved.