Preventing Catastrophic Failure by Timely RCA Intervention & Fault Restoration.

Abstract

Abstract This RCA case study has been initiated before the Gas Turbo generator failure took place by timely intervention when the Gas Turbine incident alarm triggered. Root cause analysis (RCA) process was introduced in ADGAS back in 2004, the process was designed to ensure the elimination of defects and incidents with an integrity exposure or causing production losses from repeating by identifying the root cause and putting in place robust actions to ensure incidents don't reoccur. The RCA process enabled ADGAS to put in place a practical methodology for the initiation and execution of an investigation to resolve an incident that could cause a significant loss in production, Loss of functions and / or process contamination, an integrity risk or a repetitive problem that had to be eliminated. The RCA findings would have to undergo a review before the findings and actions are approved and issued. LG6 Gas Turbine is generating 1/3 of Das Island electrical power and very critical for ADMA / ADGAS production sustainability. In May2011 LG6 encountered a severe failure of its Gear Box, entire mechanical package misalignment, load coupling compression, severe foundation tilting and load gear box tilting. The inspection findings revealed a high risk of coupling destruction and production losses. Risk assessment highlighted that if the coupling damage while machine running, it could cause a flying objects to surrounding by 30.5 meters away and 4 meter width. This RCA case study has been initiated before the LG6 power generation Gas Turbine failure took place by timely intervention when the Gas Turbine incident alarm triggered. Risk has been assessed and decision made to shut down the machine immediately for site investigation and remedial actions. RCA team members faced a big challenge to get the machine back in service safely and efficiently as soon as possible to save the plant production and avoid bad reputation of partial electrical power off- black out. This also saved a company a rental fees of pack up power generation unit (estimated 24 MM US$ for two years) and assure providing of the required power to keep the operation of LNG, OAG trains and commission of IGD projects on time with no power shortage. This project resulted in significant potential enhancements for all of the ADGAS Turbo machinery units through the innovative application of a proven root cause analysis and remedial actions to identify the truly underlying "root causes" of incidents and developing sustainable repairs. Using a fault tree analysis process this project successfully identified 85 critical possible causes for the rare Frame 5 Gas turbine fault, eliminate by verification one by one pinpointed the cause of failure and developed a repair actions that prevent failure reoccur.