Manufacturing bill-of-material planning

The bill-of-material (BOM) in the machine tool industry takes two different forms in design and manufacturing functions: Engineering BOM (E_BOM), which is used by the design engineer to represent designed product structure; and manufacturing BOM (M_BOM), which is used by MRPII system for MRP explosion. The designer constructs the E_BOM after the product has been designed. Next, the E_BOM is transformed into the M_BOM by considering assembly sequence and constraints. Constructing a M_BOM simply involves compressing the E_BOM into a three-level M_BOM. Planning of a M_BOM still depends primarily on the experience input of a manufacturing engineer and is performed manually. This trial and error and time consuming approach creates an inconsistent method for planning the M_BOM. Therefore, in this study, a three-stage M_BOM planning method is developed. Stage one plans the initial M_BOM, stage two improves the M_BOM and stage three tunes the M_BOM. Concepts and algorithms of each stage are highlighted in this study. Moreover, an illustration is presented to demonstrate the feasibility of M_BOM planning.