Mathematical Model of Multi-item Spare Parts Reservation

A mathematical model for determining the optimal number of reserved spare parts in the warehouse of an enterprise operating transport and technological machines is proved and tested. The solution of this problem is important in improving the efficiency of technical operation of machines and equipment used in any enterprise. The market conditions of management require a higher level of spare parts demand planning, a new level of spare parts supply system management. The purpose and tasks of economically justified spare parts reserves are to maintain the rolling stock in working condition in the absence or minimal downtime of machines waiting for repair due to the lack of spare parts. To do this, it is necessary to have the optimal number of required spare parts in the warehouse of the company that operates or repairs the machines. The paper is devoted to the rationale for making optimal economically sound management decisions to provide spare parts for any equipment by creating and implementing the procedure and methodology for reserving spare parts in the form of a mathematical model that takes into account a sufficient number of factors and relationships between controlled and uncontrolled variables. An example of calculating the optimal number of spare parts to reserve, de-pending on the distance to the source of spare parts, is given. The results of the calculations confirm the adequacy of the proposed mathematical model to the real production conditions.