Program manajemen perawatan pulverizer unit 1-4 dengan metode risk based inspection pada PT. Indonesia Power-Unit Bisnis Pembangkitan Suralaya

HAKIM, Lukman, Ir. Sutrisno, MSME., Ph.D

2009 | Tesis | S2 Teknik Mesin

As the largest power station in Indonesia, Suralaya power station has a very important role in contributing electricity energy supply to the Java Bali power System. The success of Suralaya to support the reliability and security of Java Bali power system depends mainly on its plant availability performance and system stabilizer performance. Fuel supply will play an important role in supporting plant’s performance such mentioned above. The reliability of coal supply will much influence the availability of Suralaya power station in generating electricity energy, and, on the other hand, the quality of coal such as heat content and chemical element content will influence the efficiency and environmental performance of Suralaya power station. Since 2003, Suralaya has been using coal from South Kalimantan that has lower quality than design. The different quality of coal could cause problems on the reliability of the function of power plant energy resources equipment, such as the pulverizer. So it is important to conduct a research to identify risks or failure and quantity the risks, in order to analyze and minimize the risk on pulverizer which could result in company loss The research analyze pulverizer maintenance cost for unit 1 – 4 by Risk Based Inspection (RBI) on Pulverizer of Suralaya power plant from 2003 until 2008. Every type of causes and influences of failure risks are analyzed by RBI methodology, while failure mechanism development are analyzed by FTA (Fault Tree Analysis). This risk management combines likelihood and consequences to find risk value for every component. Then the risk values is ranked to find out which component has the highest risk value . Analysis with Matlab6.1 for gamma distribution is used to analyze the highest risk component data (including inspection cost, failure cost, and replacement cost). Inspection of highest risk component data is later used for analyses prior to inspection, perfect inspection and imperfect inspection. The result of analysis is drawing gamma distribution. The safety margin used to analyze time maximum, time of failure, time of replacement, and time of horizon. So the estimate of highest risk component maintenance cost, interval of inspection and time of failure are found. From the analytical result, it is known that the component of Pulverizer with the highest risk value is Tire and Grinding Ring Segment (GRS). The pulverizer unit 3 is better than the other units, having an interval time of inspection before 2.5 years with average cost of replacement 155 million rupiahs. Interval time of inspection 4500 hours that made by PT. Indonesia Power UBP Suralaya basically not problematic, even enlarged the range interval inspection with attention to each unit of other critical components, By performing maintenance based on risk priority, it is hoped that the company could focus on components with high value risk. One of the efforts that company can do is to optimize its maintenance intervals, in order to reduce the risk failure.

Kata Kunci : Risk Based Inspection (RBI), FTA (Fault Tree Analysis), Pulverizer, Tire, Grinding Ring Segment (GRS)