KAJIAN CYCLE TIME UNTUK MENGURANGI ANTRIAN DAN KETERCAPAIAN TARGET PADA PENGUPASAN OVERBURDEN DI PT. TAMBANG RANTAU UTAMA BHAKTI, LAHAT SUMATERA SELATAN

Abstract

PT Tambang Rantau Utama Bhakti is a company engaged in the coal industry, established on September 22 2017 in West Merapi Village, Lahat, Palembang. The mining system implemented by PT. Bhakti Rantau Utama Mine is an open pit mining system (surface mining) with a backfilling method, in which the pit that had been completed in the mine is covered again with piled up soil from the results of overburden stripping. One of the mining activities is overburden stripping which aims to remove overburden material which is then transported to a landfill (disposal). In overburden stripping activities, diggers and conveyances are needed as tools for the processing process, this greatly influences production achievement. The purpose of this research is to find out the efforts made so that queues can be overcome, find out the causes of overburden stripping targets that are not achieved and ways to deal with it, knowing how to increase the overburden stripping achievement. This research uses direct observation method with several stages, namely: field observation, data collection, data processing and data analysis. From the results of direct observations in the field, the overburden stripping target set by the company is 55,000 BCM/month with 6 units of dump trucks. Based on the results of analysis of actual Overburden Stripping data obtained for the galiloading equipment of 52,917 BCM/month with a work efficiency of 0.57% and for the conveyance 48,473 BCM/month with a work efficiency of 0.47%. Overburden stripping was not achieved due to queue time at the front loading and reduced effective working time due to work constraints that could be avoided, for example: taking longer breaks, stopping work early, being late at the start of a shift, etc. Efforts to overcome these queues are calculated based on queuing theory simulations. From the results of the queuing theory simulation, it is obtained that the number of dump trucks needed is 5 units, then an increase in effective working time is carried out by improving the time for work constraints that can be avoided, so that the overburden stripping results obtained for the galiloading equipment are 58,487 BCM/month with work efficiency 0.63% and transportation equipment 56,631 BCM/month with a work efficiency of 0.61%