Model of Spare Parts Inventory Management in the Supply System: The Case of the ‘Oll Trak Parts’ Company

Abstract

The article identifies the relevance of the problem of optimisation of material reserves of a company and their effective management, as the state of existing reserves has a decisive impact on the competitiveness of the company, its financial condition, and the corresponding performance results. It allows the formulation of the research objective in this development. It is a given that inventory management technology is an integral part of the management system of any manufacturing and trading company. The efficiency of these companies depends on such critical criteria as the number of costs incurred for inventory management. Traditional indicators, such as inventory volume, resource turnover, and continuity of supply, cannot be used in isolation to accurately measure the extent to which an inventory management system is improving since they are part of the overall cost criterion. The article examines scientific developments of theoretical foundations for implementing rational solutions in the supply chain, where the authors use modern research methods and approaches. After analysing these studies, we identify the main problematic issues: determining a rational way of servicing orders by the core production warehouse systems, organising an efficient product supply form, and developing rational inventory management technologies throughout the entire product supply chain. We create a structural model of interaction between the warehouse system of the ‘OLL TRAK PARTS’ company and suppliers and customers, formed with the participation of certain parties in all relevant operations. The structure of stocks accounts for the customer’s needs in a multi-nomenclature offer of spare parts for trucks, cars, and agricultural machinery supplied by ‘OLL TRAK PARTS’. The authors build a mathematical model of spare parts inventory management under limited demand conditions, which considers the following parameters of influence: the period for ordering spare parts, the cost of supplying ordered spare parts, and the cost of storing one unit of spare parts inventory. To achieve maximum measurement accuracy with a minimum number of trials and to maintain the statistical reliability of the results, we develop a full-factor experiment plan for three input parameters with three levels of values, consisting of 27 series of trials. The experiment allowed us to model the change in minimum costs with different order volumes of spare parts. Based on the results of the regression analysis of the obtained values of the estimated indicator, we determined the type of regression model – a linear form with a non-zero coefficient. Keywords: model, warehouse, system, logistics, interaction.