Material requirements planning system considering batch size and minimum order quantity for items of suppliers

Abstract

Abstract Material requirements planning (MRP) is an intelligent information system and a decision maker that determines the type of raw materials, the amount of them, and their supplying time in order to realize production schedule of products and work-in-process items in a manufacturing system. The inputs of MRP model include bill of materials, master production schedule, lead times, and inventory of the items. The main output of the model is material supplying schedule, and MRP sub-outputs include purchase advice, control report for the consumed items, financial planning, budgeting, and so on. If in each manufacturing system we split production costs into three kinds of raw material costs, salary costs, and overhead costs, in the real environment, 60-90 percent of total costs are related to raw material costs. Therefore, in each manufacturing system, it is necessary to consider an appropriate inventory control system to control the costs of inventory system and provide right inventory, with right amount, at the right time, at the right price, and with appropriate quality. In this research, two constraints on the size of the packaging of goods and the minimum order amount that a supplier provides for a product are added to the model. By closing the existing gap, the mentioned model can be operationally implemented and provide appropriate decision-making outputs. Therefore, at first, we will review the introduction and previous researches that have been done in this field. Then, we will describe the components of the material requirements planning model. In the following, the above-mentioned two constraints are added to the model and the material requirements planning system is presented.