Strategy for capacity management of batch constrained heat treatment operations in the manufacture of multiproduct families

Heat treatment applied in alloy casting and related industrial processes improves mechanical properties achieving stress relief and alloy hardness. However, in a batch-manufacturing environment involving manufacture of multi product families with limited resources, capacity management becomes critical. This paper describes capacity management of heat treatment resources in a manufacturing environment with multiple variables affecting process flow, with an objective to achieve cost, time and capacity effectiveness of heat treatment resources within operational constraints. Variable scrap levels, non-optimal load efficiencies, engineering change orders and rework affect capacity utilisation making it difficult to satisfy target delivery due date commitment to customer. In conclusion, optimal policy to control batch processing machines serving compatible job families cannot be generated by simple scheduling rule but by a heuristic policy.