Perencanaan Pengendalian Lot Pemesanan Pasir Untuk Produk Beton Pracetak Menggunakan Metode EOQ Dan Algoritma Wagner Within Dengan Batasan Kapasitas Gudang

Endang Saefullah; Aries Sudiarso; Ade Muhammad

Authors

Endang Saefullah Universitas Pertahanan Republik Indonesia Author
Aries Sudiarso Universitas Pertahanan Republik Indonesia Author
Ade Muhammad Universitas Pertahanan Republik Indonesia Author

Keywords:

Perencanaan, Persediaan, Bahan Baku, Kendala Kapasitas Gudang

Abstract

The current administration's accelerated development of national infrastructure requires the precast concrete industry to optimise its performance, particularly state-owned enterprises, which play a strategic role in supporting development policies. Effective control of raw material supplies is essential for achieving production targets and operational cost efficiency. This study aims to optimise the sand inventory control system at PT Wijaya Karya Beton Tbk by applying the Economic Order Quantity (EOQ) method and the Wagner–Whitin algorithm, while taking warehouse capacity limitations into account. A quantitative approach is used to compare the effectiveness of the EOQ method and the Wagner-Whitin algorithm in optimising sand inventory in 2020. The analysis considered ordering and storage costs, as well as a maximum warehouse capacity of 18,015 m³. Implementing the EOQ method produced an optimal ordering policy of 9,750 m³, which remained within the warehouse's capacity limits. This strategy resulted in total inventory costs of IDR 1,864,095,810, achieving an efficiency level of 94% compared to the company's conventional inventory system. The EOQ method has proven superior in optimising control of the sand inventory by providing significant cost efficiency without exceeding warehouse capacity limits. These findings support the company's achievement of its strategic targets in relation to the national infrastructure development programme.

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