MRP is a computer-based information system designed to handle ordering and scheduling of dependent-demand inventories. Material requirements planning was pioneered by Joseph Orlicky, George Plossl and Oliver White. The Educational Society for Resource Management, formerly know as the American Production and Inventory Control Society, has also been instrumental in broadening the understanding of MRP through its educational programs. MRP is as much a scheduling philosophy as it is an inventory control technique. MRP is a disciplined approach to inventory control; it requires a high degree of discipline on the part of the implementor/user. .
Material requirements planning is not a quick fix that will solve all your inventory woes overnight. It is nothing more that an inventory control tool that requires considerable resource in order to implement and maintain. A typical MRP implementation can take anywhere from 6 months to 2 years. MRP is not Closed-loop MRP, MRP II or ERP. One of the limitations of MRP is that it is designed only to identify material requirements. It ignores all other manufacturing resources, such as capacity, tooling, machines, etc. Because MRP ignores capacity it is said to plan in infinite capacity, as capacity is not a constraint. This can be a real problem for a lot of companies due to the fact that capacity is most definitely a real constraint and needs to be accounted for. .
Inputs to MRP.
The three primary inputs into the MRP program are the master production schedule, the bills of materials, and the static and dynamic inventory data files. The master production schedule consists of demand data for the finished items. The demand sources include customer orders, sales forecasts, inter-plant demand and the master schedulers gut feel. It is important to note that the master scheduler plays an important role in the refining and tailoring of the master production schedule because the master scheduler usually has a keen insight into the effects of information from sales and marketing on the master production schedule.
