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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...
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    LP Steam Generation Higher Than Design

    HRSG LP steam is utilized in De-aerator for de-aeration of condensate from steam turbine. During base load operation of plant, LP steam is combined with HP extraction steam to meet the requirement for de-aeration of water. During partial load operation, HP steam generation is reduced which...
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    GE Fr9E Turbine Inner Barrel Temperature

    During ramping up of GT (GE Fr9E) from 60MW to base load (125MW), turbine inner barrel temperatures start rising from 120 Deg C to 195 DegC, and Load compartment temperatures rise from 95 Deg C to 145 Deg C. As Load compartment reaches 145 Deg C, Load compartment fan#2 cut in and temperature of...
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    HRSG Burners High Spread

    HRSG gas burners are experiencing high spread reaching to 120 Deg C spread on partial load (4 out of 8 burners in operation) as compared to 60 Deg C spread on base load (8 out of 8 burners in operation). Partial load operation also have changed the stack smoke from clear to yellowish. What is...
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    GT Frame 9E Lube Oil Header Pressure Reduced

    Gas Turbine frame 9E lube oil header pressure reduced from 4.3 bars to 3.6 bars after shutdown. Before shutdown, lube oil header pressure was around 4.3 bars and plant was shutdown for HRSG maintenance activities. Only hydraulic oil filters on valves inspection was carried out during outage...
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    Gas Turbine FR9E High Exhaust Pressure

    Gas Turbine GE Frame 9E in combined cycle operation is experiencing high exhaust pressure reaching 15Kpa. Following is the concern: 1. What can be the reason for high exhaust pressure 2. What impact it can cause on Gas Turbine performance.
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    GE Frame 9E Bleed Off Valves Passing

    Gas turbine main filter replacement activity was carried out in foggy conditions, and after that off line water wash not carried out. After one day, compressor efficiency was reduced. Later it was identified that GT generating 4Mw less as compare to before filter replacement activity...
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    GE Frame 9E Increasing Exhaust Spread after Fuel Change Over

    Gas turbine GE Frame 9E undergone fuel change over from Gas to Hsd occured due to Gas field tripping and GT MW went form 120 to 150MW. GT MW fluctuating for 2min before get stable. After 24 hours of event, GT exhaust spread is on increasing trend and has increased from Avg 33 to Avg 36 in...
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    Gas Turbine Frame 9E Hydraulic Pressure Filter Replacement Alarm

    During change of Gt hydraulic filter, the commuter valve was broken. GT Fr9E Hydraulic pressure filter alarm is persisting on DCS for over 2 days now. We are monitoring the hydraulic pressure and have no other way but to shutdown the unit and replace the assembly. Is there any alternate way...
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    Condenser Ball Cleaning System

    Steam Turbine Condenser is equipped with online rubber ball cleaning system. The system currently is out of order due to lost rubber balls. The balls sent in is not equal to balls received after washing. How much impact will it have on Steam turbine efficiency? What can be the reason for...
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