Lot sizing and variable periodic consumption based stock ordering in an automotive supplier company

As a result of the effects of the globalization process, companies emphasize the importance of inventory holding and ordering process. In busines life, the aim of all companies are to make profits. In order to realize this purpose and continue their existences in market, companies should have some values and these values should be always ready to use. One of them is called inventory. Inventory management process starts from purchasing the raw materials and continues to sales of finished goods to customers. In order to manage the inventory process efficiently, companies should choose the best methods to order and control them. This gets more difficult if the product variety is high. Especially if the customer demand variation is high, companies gets more difficulties to meet their needs. These kinds of factors cause customers' compliances. Companies should keep enough stock to meet the demand in market. Inventory holding cost in high for all companies. In the mean time, stockout costs are also very high. In this scope, it gets vital to determine the optimum lot sizing policy and optimum minimum stock holding policy. Another important factor is to determine how much inventory should be kept from each product. In order to determine this, an ABC analysis can be used. So that the unnecessary inventory can be avoided. This will also decrease ordering cost, holding costs and related costs. In this study, the actual method will be discribed and different lot sizing methods will be searched to understand the optimum method. In the mean time, customer's actual minimum stock policy will be defined and new methods will be searched to ind the best solution. Before to start searching, an ABC analysis will be performed to understand the value in total for each product and best lot sizing method will be searched for each group in ABC analysis. Keywords: Inventory, Stock, Buffer, Lot Sizing, Automotive, Inventory Management, ABC analysis