Usulan Kebijakan Pengendalian Persediaan Bahan Kimia Menggunakan Distribution Free Continous Review (q,r) Untuk Meminimasi Biaya Persediaan Pada Unit Pengolahan Air Pendingin

Abstract

Abstrak Unit Pengolahan Air Pendingin di PT. Pupuk Kujang Cikampek (selanjutnya disebut PKC) berfungsi menjaga kualitas airnya dengan menggunakan bahan kimia. Unit Pengolahan Air Pendingin belum menggunakan perhitungan baku. Kebijakan persediaan diambil dengan cara perkiraan semata. Keadaan ini mengakibatkan terhadinya overstock yang menyebabkan permasalahan bengkaknya total biaya persediaan. Peneliti diharapkan dapat memberikan usulan metoda kebijakan pengendalian persediaan yang tepat untuk meminimasi total biaya persediaan. Berdasarkan perhitungan menggunakan metoda Distribution Free Continuous Review (Q,r) With Service Level Constraint didapatkan total biaya persediaan sebesar Rp 207.944.636, sedangkan nilai aktual sebesar Rp 413.437.333. Berdasarkan analisis sensitivitas diketahui bahwa perubahan parameter pada biaya simpan memberi pengaruh lebih signifikan pada total biaya persediaan dibandingkan perubahan parameter biaya pesan. Berdasarkan pengolahan dan analisis data dapat disimpulkan; bahwa model Distribution Free Continuous Review (Q,r) With Service Level Constraint dapat digunakan sebagai usulan kebijakan pengendalian persediaan karena dapat menurunkan total biaya persediaan sebesar Rp205.992.697 (49,82%). Peneliti menyarakankan agar secara kontinyu dilakukan pemeriksaan tingkat persediaan pada saat adanya pemakaian bahan kimia, dan apabila tingkat persediaan telah menyentuh reorder point (r) kebijakan usulan, maka perlu dilakukan replenishment dengan quantity (q) yang sesuai dengan kebijakan usulan menggunakan Distribution Free Continuous Review (Q,r) With Service Level Constraint. Kata kunci: continuous review, overstock, kebijakan persediaan, service level, analisis sensitivitas Abstract Cooling Water Treatment Unit at PT. Pupuk Kujang Cikampek (called as PKC) functions to maintain the quality of its water by using chemicals. The Cooling Water Treatment Unit has not used standard calculations. Inventory policy is taken only by estimation. This situation resulted in overstocks which caused problems with the swelling of the total cost of inventory. The researcher is expected to be able to propose the right method of inventory control policy to minimize the total inventory cost. Based on calculations using the Distribution Free Continuous Review (Q, r) method with Service Level Constraints, obtained total inventorty costs of Rp 207,944,636, while the actual value is Rp 413,437,333. Based on the sensitivity analysis, known that the changes in holding cost parameter is more significant than changes in the ordering cost parameter. Based on data processing and analysis it can be concluded; that the Distribution Free Continuous Review (Q, r) with Constraint Service Levels can be used as proposal policy due to its saving of total inventory costs as much as Rp205,992,697 (49.82%). The researcher suggests that to monitoring continuously the inventory level of chemicals when using chemical, and everytime the inventory level is touching the reorder point (r) of proposal policy, it is necessary to replenish as much as quantity order (q) according to the proposal policy using Distribution Free Continuous Review (Q, r) method with Service Level Constraints. Keywords: continuous review, overstock, inventory policy, service level, sensitivity analysis