Maintenance and safe operation of gas turbine are critical for ensuring reliability, efficiency and longevity of equipment. Due to the hot section high temperature, pressure, and rotating speed involved, proper maintenance practices such as level one borescope inspection, and level two routine component replacement are vital to avoid breakdowns, and minimize downtime and maximize operational performance. The operation of gas turbine also requires a careful condition monitoring and control system to optimize performance and preventing equipment sudden failure. Condition monitoring techniques such as vibration analysis, oil analysis and thermography, help detect early warning signs of equipment degradation, lubrication issues or potential component failure. This paper investigates gas turbine 4B bearing failure, on sump B scavenge chip detector, in liquefied natural gas (LNG) plant. Cause and effect analysis five whys and fishbone, were conducted and the main root causes were identified as external hard particles contamination (Al and Si oxides) which include spalling in bearing component, as confirmed by laboratory analysis, chip detector alarm and sump B scavenge oil high temperature. Metal shavings found on sump B chip detector, strainer found with metal flakes, inside the strainer found bolts, nuts and looking wire. Condition monitoring trends were critically analyzed and presented.
Eloi S Pereira (Wed,) studied this question.