Order release and product mix coordination in a complex printed circuit board manufacturing line with batch processes

In this paper, we study the role of order releases and product mix coordination in a complex manufacturing line with batch processors. We develop a planning methodology for synchronizing production in such manufacturing lines and discuss the decision-making process in the context of a PCB production environment at Northern Telecom's Fiberworld Division. The planning methodology includes developing mathematical programming models for determining a configuration of batch processors, order releases to the shop floor, and daily loading decisions at the batch processors. The optimization models are linked to a simulation model of the shop, which provides key statistics like lead time, work in process, and utilization rates. The objective is to reduce lead time for manufacturing different products in this environment while meeting the demand. We analyze the performance of such a line, study the efficacy of various types of shop floor synchronization policies, and establish the role of batch processors in managing such complex lines effectively. We exhibit how batch processors (which are bottleneck operations) could be scheduled effectively to incorporate the logical constraints that govern their operations and react to variabilities in the manufacturing line.