Analisis Penurunan Capaian Target Produksi Bijih Nikel Menggunakan Metode Fault Tree Analysis di PT Ifishdeco Provinsi Sulawesi Tenggara
Authors: Anas Aryanti Virtanti , Parissing Yoshita P , Nur Irzal , Sufriadin Sufriadin , Purwanto Purwanto , Thamrin Meinarni , Prasetyono Agus 
Published: October 2020

Abstrak
Proses produksi berarti menghasilkan suatu produk yang bernilai guna. Dalam suatu perusahaan pertambangan, produksi merupakan hal yang sangat penting, sehingga diperlukan perencanaan yang matang. Perusahaan menargetkan jumlah bahan galian yang akan diproduksi baik dalam jangka panjang, menengah maupun jangka pendek. Operasi produksi PT. Ifishdeco menggunakan bantuan alat gali muat excavator Komatsu PC 300 dimana terjadi penurunan produksi bijih nikel sebesar 19,94%. Target produksi sebesar 149.934 mt, namun capaian produksi hanya sebesar 116.603mt. Oleh karena itu, penelitian ini dilakukan untuk mengetahui faktor utama dan nilai probabilitas penyebab turunnya capaian produksi. Salah satu metode yang dapat digunakan untuk menganalisis faktor utama penyebab penurunan capaian produksi adalah menggunakan Fault Tree Analysis (FTA). Persamaan logika top down dari Fault Tree Analysis disubstitusi ke dalam aljabar Boolean hingga diperoleh minimal cut set. Minimal cut set merupakan persamaan akhir yang merincikan top down. Top event penurunan capai target produksi memiliki empat top down, yaitu faktor pengisian, kesiapan fisik alat, efektivitas kerja, dan waktu edar alat gali muat. Berdasarkan nilai probabilitas basic event tertinggi yang bernilai 1, maka faktor utama penyebab penurunan capaian produksi adalah dari faktor umur pakai alat tua, penjadwalan perawatan tidak teratur, kualitas alat buruk, dan proses selective mining.

Abstract
Analysis of Decrease in Nickel Ore Production Targets Using the Fault Tree Analysis Method in PT Ifishdeco, Southeast Sulawesi Province. Production process meant produce product with beneficial value. At the mining company, production was very important, so it needed to be well-planned. Company was making target amount of digging material to be produced in long term, middle term, and short term. Production operation at PT Ifishdeco utilized digger loader equipment namely excavator Komatsu PC 300. There was decreasing in nickel ore production of 19,94%. Production target was 149,934 mt, but the company was only able to meet 116,603 mt. Objective of this study was to know main factor and probability value which caused the low production performance. One of methods to be used to analyze the main factor was Fault Tree Analysis (FTA). Top down logical equations of Fault Tree Analysis was substituted into Boolean algebra to get minimal cut set. Minimal cut set was a formula of the top down and used to calculate probability. Top event of the decreasing of the production target had four top downs which were filling factor, mechanical availability, effectivity of use, and cycle time of digger loader. Based on the highest probability of basic event which value was equal to 1, the main factor caused the decreasing of productivity were lifetime of equipment, unscheduled of maintenance, low quality of equipment, and selective mining.

Kata Kunci: Excavator, Work Effectivity, Boolean, Cut Set, Probability