Recent content by AAkhan

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    High Vibration at Low RPM on high capacity Vertical Centrifugal Pump

    Thanks CSA for the enlightenment. We have taken up the issue with OEM and have raised warranty claims also and after sharing the Vibration Analysis report, we had same response from them as its because of piping frequency interference. And we have previously started these pump by bypassing the...
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    High Vibration at Low RPM on high capacity Vertical Centrifugal Pump

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    High Vibration at Low RPM on high capacity Vertical Centrifugal Pump

    Yes we have performed the FFT and the cause is structural resonance because of piping and we intend to eliminate by installing the flexible bellows. But for that we need outage and for now our reliability is being compromised hence we need to add a specific time delay to overcome that issue for...
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    High Vibration at Low RPM on high capacity Vertical Centrifugal Pump

    Thanks for the response Following are the remarks My First question would be where did this vibration spike located ( bearing , surface?? ) Vibration spikes are located on Pump DE and Motor DE side bearings. What is the vibration monitoring rack system Model/type & Instrumentation OEM...
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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

    Thanks for the detailed response and feedback. We will expect answers from OEM in this scenario. Moreover, i have made some progress in stated issue 2 days back. During last pump changeover, there are 03EA DP sensors and all were showing values above 0 and these 03 DP valves are then being...
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    Lube Oil Leakage from H2 Cooled Steam Turbine Generator Bearings seals

    Thanks for the feedback. I have posted another thread in which we are facing ST generator seal oil DP issue. Please heck if you help me figuring out the root cause. https://control.com/forums/threads/st-h2-generator-seal-oil-delta-pressure-drops-to-0-during-pump-change-over.48832/ Thanks
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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

    Thanks for the response. I think there is some mis-understanding. Let me clear my question again. We have "Lube Oil Leakage" from Steam Turbine bearings oil seal at Balloki Site. The lube Oil returns to Main lube oil tank. The main lube oil tank is maintained under vacuum. Now following are the...
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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

    CSA, Thanks for your prompt response. Issue was resolved after replacing the fuel bypass valve and filter.
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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...
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    GE Fr9E Turbine Inner Barrel Temperature

    >When did this problem start? After a maintenance outage? If >so, and novice001 is correct, it's possible the number and >location of open holes needs to be tuned after the outage. We cannot link it with outage since the adjustment of Exhaust frame cooling blowers discharge pressure...
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    GE Fr9E Turbine Inner Barrel Temperature

    Hello, >Let me understand by inner barrel do you mean the load >tunnel area where bearing no 3 is housed? > >In this area maximum temperature is controlled by radial air >flow holes which provide part of shell cooling fan air to >this area. The number and location of open holes is...
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