MRP for Multilevel Flexible BOM

Abstract

The Bill of material (BOM) along with the demand is used for making the master production schedule. While all aspects of production are considered as variable traditionally the BOM is invariable i.e. the quantity of parts / sub-assemblies for final product are fixed. In master production schedule time of manufacturing is also not variable with an inflexible bill of material. If there are shortages in any of the components / sub-assemblies of the final product then traditionally in MRP the shortage is compensated by ordering extra in future orders of raw materials and final product deliveries may be delayed. This work presents a method of compensating for the shortage by varying the BOM within tolerant limits. The compensation for a two level BOM from literature is improved to incorporate a compensation for a multilevel BOM. With the help of this when shortage occur in any sub assembly in second level or in any component in a lower level then a new bill of material is formulated with help of a linear programming model. The requirements of final product (like top assembly) stated in the master production schedule are met in given time by the substitution of other components or produce with a decreased number of components which are within tolerant limits. This concept is developed for multi levels but an example of top assembly is taken for three levels for presenting the concept.