Inventory is an important factor in carrying out a production. Many companies experience problems in terms of inventory control, one example is inventory scarcity. The purpose of this study is to optimize the need for goods so that the company will not experience problems with inventory shortages or inventory buildup. This study uses  the Min-Max method  by collecting data in the form of inventory of goods needs, ordering costs, and storage costs. The result of this study  is that the safety stock value  of 80,887-tons is useful for protecting and anticipating inventory shortages, so companies must be on guard when they are at that value. Then, the Reorder Point value was obtained at 108,165 tons. Furthermore, the value of the Minimum Inventory  is 269,879-tons and the Maximum Inventory is  378,044-tons so that companies are not recommended to have more inventory than that value.
 
 

Mitsubishi Chemical Indonesia is a producer of Purify Terepthalic Acid (PTA) in Indonesia with an important role in meeting the primary needs of the Indonesian population by managing raw materials to produce purified terepthalic acid. Purified terepthalic acid is the main raw material for polyester fiber. The problem that occurs is the phenomenon of the bullwhip effect, namely the occurrence of fluctuations between orders and demand which results in a shortage of raw materials or low inventory which can cause production to stop. So the purpose of this study is to calculate the value of the bullwhip effect, determine the causes of the bullwhip effect, and determine solutions to reduce the bullwhip effect. This study begins by calculating the value of the bullwhip effect at the two echelons. The method used in this research is FMEA. The results of this study are the value of the bullwhip effect at echelon 1 (suppliers and PPIC) = 1.27 and echelon 2 (PPIC and distributors) = 0.93. This value indicates the occurrence of a bullwhip effect in echelon 1 while echelon 2 does not indicate the occurrence of a bullwhip effect. The dominant causes of the bullwhip effect are market competition, rising material prices, demand forecasting that is not close to accurate and the number of orders for raw materials in large quantities. The proposed improvement is to collaborate with suppliers and customers to get guaranteed orders and demand that are fixed and sustainable. This value indicates the occurrence of a bullwhip effect in echelon 1 while echelon 2 does not indicate the occurrence of a bullwhip effect. The dominant causes of the bullwhip effect are market competition, rising material prices, demand forecasting that is not close to accurate and the number of orders for raw materials in large quantities. The proposed improvement is to collaborate with suppliers and customers to get guaranteed orders and demand that are fixed and sustainable. This value indicates the occurrence of a bullwhip effect in echelon 1 while echelon 2 does not indicate the occurrence of a bullwhip effect. The dominant causes of the bullwhip effect are market competition, rising material prices, demand forecasting that is not close to accurate and the number of orders for raw materials in large quantities. The proposed improvement is to collaborate with suppliers and customers to get guaranteed orders and demand that are fixed and sustainable.

 
 
 

Waskita Beton Precast is a company engaged in manufacturing. The products produced include Spun Pile diameter up to 1200mm and other girder products. Every company must have Personal Protective Equipment (PPE). Personal Protective Equipment (PPE) is an effort made to protect or prevent the risk of accidents and also as a complete form of other accident prevention efforts. Therefore, logistics management is needed to meet the needs of personal protective equipment in companies. The purpose of this research is to find out the process of obtaining raw materials and knowing inventory control. The method used is descriptive analysis. The results of this study are that companies obtain personal protective equipment from distributors who have worked with the company. PT. Waskita Beton Precast pre-orders personal protective equipment and completes payment so that personal protective equipment can be sent immediately.