The present invention relates generally to manufacturing rework processes, and more particularly, the present invention relates to a method, system, and storage medium for integrating rework operations into an advanced planning process.
In a manufacturing environment, the process of rework refers to the handling of products and assemblies that are found to be defective, either because the manufacturing process is flawed or because one or more components of the product of manufacture is flawed. The flaws are often detected during a testing procedure that occurs at a specified point in the manufacturing process such as the completion of a subassembly fabrication.
Despite these defects, many products can be reworked by replacing defective components in the products or assemblies or by repeating a particular operation in the manufacturing system. Assemblies that cannot be reworked may be a source of “salvageable” component parts whereby the assembly is broken down and the working components are kept. Salvageable components are then fed back into the manufacturing process. The processes involved in conducting rework and salvage in a manufacturing system translate into circular material flows of component parts. Advanced planning systems have attempted to manage this circular material flow, but with little success.
Advanced planning systems (APS) are used to optimize supply chain planning decisions. They leverage mathematical models (e.g., linear programs) to optimize planning decisions including the build plan for the manufactured parts (e.g., assemblies, subassemblies, components) at the manufacturing plants in a division, interplant logistics, and customer shipments. To determine the optimal plan, they trade off several criteria to determine an optimal allocation of limited work center capacity and material supply to best meet a prioritized customer demand statement.
For industries with a significant rework aspect to their manufacturing system, it would be beneficial to provide the details of the rework process to the APS so that the impact of two-way material flows in the plan can be captured. This would involve providing detailed information about the rework bill of material (BOM), capacity resources required for performing rework operations, replacement parts sorting percentages reflecting the fraction of parts requiring rework, and cycle times for completing rework operations. With this information, the rework process can be integrated with the APS mathematical model.