Method Of Valve Preventive Maintenance Via Additional Overview On Pos For Decreasing Failure Risk At Starting And Change Over Fuel Gas To Fuel Oil In Block 1 And 2 Gas Turbine GT13E2 PT. PJB UP Muara Tawar

Block 1 and 2 Combined Cycle Power Plant (CCPP) Muara Tawar have 5 units gas turbine can be operated by using fuel gas. Due to limitation of fuel gas from gas company. Several gas turbine are operated using High Speed Diesel fuel (HSD) to fulfil load demand. The equipment that used for fuel gas system must have high realibility to serve in dual fuel system neither operated using fuel oil or gas without unit trip. In actual, there are several disturbances occur during change over from gas to oil, even when the plant operated using fuel oil. From the data of failure causes, one of the failure causes is valve failure. By considering the availbility of plant, in term of possibility to modify instrumentation and control system, gas turbine 1.3 was choosen as object of the study. Additional indicator in HMI can be described as follows additional pressure switch attribute at EDS-P3 using symbol K, upload program to EPROM at card 70BK06 as communication card, and the cycle time less than 1 second in both valve open or close. It indicate valve system under good condition or no maintenance action is required. Valve maintenance at gas turbine ALSTOM 13E2 in Block 1 and 2 CCPP Muara Tawar can be done by additional indicator of pressure switch and aux relay contact as feedback signal on POS 30. Therefore, no disturbances in valve system and gas turbine performance increases.