Recent content by AAkhan

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    High Vibration at Low RPM on high capacity Vertical Centrifugal Pump

    We have a vertical type muti-stage centrifugal pump which operates at 1500 RPM and has smooth operation with vibration limit max of 0.8mm/sec RMS. During shutdown or start-up when the said pump reaches 80 to 90 RPM, its vibration increases significantly i.e. above 80 mm/sec RMS and causes...
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    ST H2 Generator Seal oil Delta Pressure drops to 0 during Pump change over

    We have Alstom Steam turbine with H2 cooled generator with capacity of 400MW with 02 9HA.01 Gas Turbines in CCPP operation. Problem Statement: During ST seal oil AC pump change over, DP for ST seal oil system becomes 0 and then returns back after few sec while seal oil pump is running. For...
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    Lube Oil Leakage from H2 Cooled Steam Turbine Generator Bearings seals

    We have Alstom Steam Turbine capacity 400MW equipped with 02EA GE 9HA turbines in CCPP of capacity 1223MW commissioned in 2018. Steam turbine generator is H2 cooled. There are leakages from STG bearing oil seals and we are searching for a root cause. Following are my questions 1. What is...
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    Maximum Axial Thrust Load in GE frame 9E

    I mean the maximum axial force that thrust bearing can withstand. I think the normal axial force is around 300 kilo newton (KN). (I do not have any reference). I need the maximum acceptable axial force that is mentioned in thrust bearing drawing or spec document.
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    VC3 Valve Hunting and Machine Tripping

    We are having trouble during the start-up of our gas turbine (MS9001E) on liquid fuel. Whenever turbine reaches upto around 2900 ~ 2950 RPM, the VC3 valve starts hunting and within 5 seconds the machine gets trip over LOSS OF FLAME signal. We have replaced VC3 servo valve, its hydraulic...