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Calculated reasons for increase in Turbine specific steam consumption

1. Lower vacuum Turbine consumes more steam, if vacuum in condenser is maintained on lower side. Example:   Consider a 20 MW Steam Turbine having Inlet steam parameters 65 kg/cm2 & 490 Deg C & Vacuum maintained in condenser is -0.9 kg/cm2. Calculate the steam consumption of turbine at vacuum -0.9 kg/cm2 & -0.85 kg/cm2 A-Steam consumption Q at -0.9 kg/cm2 to develop 20 MW power P =Steam flow X( Enthalpy of inlet steam-Enthalpy of exhaust steam)/ 860 Enthalpy of inlet steam at inlet steam parameters =810 kcal/kg Exhaust steam enthalpy at -0.9 kg/cm2 vacuum = 619 kcal/kg Then, 20 = Q X (810-619)/860 Q1 = 90 MT B- Steam consumption Q at -0.85 kg/cm2 to develop 20 MW power Exhaust steam enthalpy at -0.85 kg/cm2 vacuum= 623 kcal/kg Then, 20 = Q X (810-623)/860 Q 2= 90.9 MT It is clear that, Turbine operating at -0.9 kg/cm2 vacuum consumes lesser steam as compared to turbine operating at vacuum-0.85 kg/cm2 2. Lower inlet main stream pressure& temp

How do you calculate the Power generation in steam Turbines??

Power in the steam Turbines produces at every stage where the steam is taken out, whether it may be bleed, extraction or exhaust steam. As the steam out from the turbine increases the power developed on that particular stage will increase. Power generation phenomenon. Power generation in steam Turbines is calculated based on difference between the heat content of inlet steam & extracted steam. Factors affecting the power generation: Power generation at particular stage increases, when there is more steam flow &vice versa Power generation at particular stage increases when there is more difference between inlet & extraction steam & Vice versa Power develop at particular stage decreases if its extraction pressure increases & vice versa Power developed at particular stage decreases if its extraction temperature increases & vice versa Power developed in steam Turbine decreases if inlet live steam pressure & temperature decrease If steam v

30-Things you must know on steam turbine & auxiliaries

1-During cold start up turbine inlet steam   minimum temperature should be saturation temperature at the particular pressure + 50 Deg C. Example: Turbine operating at 67 kg/cm2 pressure, its inlet steam temperature should be285+50 =335 deg C 2-Distinguishing the Turbine starts up types. Cold start up - when HP and IP inner casing temperature is lower or equal 170 o C Warm start up- when HP and IP inner casing temperature is lower or equal 430 o C Hot start up – when HP and IP inner casing temperature is greater than 430 o C. Read Power generation phenomenon in STG 3-To open ESV the vacuum should be at least 0.3 Kg/cm2A (-0.73 kg/cm2) 4-In turbine rotors, over speed trip bolt is always fitted at the DE side only. This is because, not weaken the Turbine NDE side shaft, as NDE side shaft size is already made small & drilled for key ways 5-Expansion bellows for lube oil lines are fitted at the Turbine front bearings , as Turbine expansion occurs towards f