PT. DSG is a manufacturing company that produces metal fitting products, with Y-Strainer as the best-selling product. The company imports raw materials with a 2 to 3 weeks lead-time period. For the product demand is fluctuating, the quantity and schedule of ordering raw materials are also uncertain. The company also experienced delays in product delivery by 50% in the past year. Therefore, they need a proposed improvement plan for forecasting and planning production, inventory, and distribution to overcome these problems. This research requires demand data from April 2018 to March 2021 and other supporting data to perform a forecasting calculation. The forecasting method for this research is SMA, DMA, WMA, SES, DES, Cyclic, Linear, Quadratic, Decomposition, and ANN forecasting methods. The next calculation is aggregate planning by shift, overtime, mixed aggregate categories and rough cut capacity planning (RCCP) using CPOF, BOLA, and RPA methods. Material Requirement Planning (MRP) using EOQ, POQ, LFL, Silver Meal, LUC, and WWA lot-sizing and safety stock calculation. The final calculation continues with Capacity Requirement Planning (CRP) and Distribution Requirement Planning (DRP). As a result, the forecasting method chosen for the Y-Strainer product is ANN, for it has the smallest error compared to other methods. Mixed aggregate planning was chosen because it has the smallest total cost. The CRP calculation shows that the capacity is greater than the needs, meaning the company can meet customers' demand from April 2021 to March 2022 with their resources. The lot-sizing technique chosen for the MRP calculation is WWA that can save 22% and distribution planning using DRP can save 52% compared to the method PT. DSG uses now. The Odoo ERP system can help the company control business operations. It is more practical and efficient with data collection being carried out automatically, in real time, and stored in the ERP database. Thus, the delivery of information among departments runs quickly and accurately, which may lead the company to minimize errors.
Keywords
Production Planning, Wagner Within Algorithm, ANN, DRP, ERP.