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Why does vacuum in steam condenser reduce or drop??

  1-High exhaust temperature: Vacuum drops or maintains at lower side due to high exhaust steam temperature flow into steam condenser. This high exhaust temperature is mainly due to 1-Operation of Turbine at lower loads 2-More clearance in labyrinth seals 3-Not operating exhaust hood sprays 4-More load on condenser 5-Breaking of ejector U loop 2-Low circulating cooling water flow Vacuum in condenser reduces due to inadequate cooling water flow through steam condenser. This is mainly due to; 1-Problems associated with pumps 2-Air pockets in pipe line 3-Leakages in cooling water line 4-Stuck of discharge valve of pump 3-High cooling water temperature at condenser inlet Higher cooling water temperature at condenser inlet results into reduction of vacuum due to poor heat transfer from steam to water 4-Poor heat transfer in condenser Very less or poor heat transfer in steam condenser reduces vacuum to very low level resulting into high exhaust temperature &am

Steam turbine practical questions & answers for Turbine engineers & operators

STEAM TURBINE QUESTIONS AND ANSWERS FOR TURBINE ENGINEERS & OPERATORS 1-Why do the U loop is provided at the inter condenser drain line of ejector? U loop is to seal the ejector & steam condenser pressure as there is very less pressure difference around 0.25 to 0.3   kg/cm2. So for such low pressure difference U loop seal is economic & practical 2-Why do the float valve are provided at the after condenser of ejector condensate line? Know about vacuum troubleshooting in steam Turbines Float valve is used to seal the ejector & steam condenser pressure as there will be around 0.89 to 0.95 kg/cm2 pressure difference. For such high pressure difference float valve is most practical arrangement. 3-Generally, where the pressure relief valves are fitted at ejector systems?                              There two pressure relief valve in SJAE (Steam jet air ejector) one is fitted at ejector nozzle chamber & other is fitted at condens

Question & answers on vacuum troubleshooting in steam turbines

Understanding  the term Vacuum. The earth's atmosphere exerts pressure upon us known as atmospheric pressure which can be measured in number of ways & methods.At the seal level the pressure measured is 760 mm of Hg, 1 Torr or 14.7 PSIa or 1 bar.Because the barometric pressure varies above seal level pressure is used as reference point. As there is 1 bar pressure exerted on our body and also there is 1 bar pressure within our body. So as per Newton's law action &* reaction are equal and opposite, we do not feel any discomfort. That is there is no any pressure difference between inside & out side of the body. Evacuating air from a closed volume develops a pressure differential between the volume and the surrounding atmosphere. If this closed volume is bound by the surface of a vacuum cup and a work piece, atmospheric pressure will press the two objects together. The amount of holding force depends on the surface area shared by the two objects and the vacuu

STEAM CONDENSER,VACUUM AND CALCULATIONS

A steam condenser is device or an appliance in which steam condenses and heat released by steam is absorbed by water. Heat is basically shell & tube type heat exchanger, where cooling water passes through tubes & steam condenses in shell. The functions of the condensers are: It condenses the steam exhausted from Turbine last stage Increase the thermal efficiency of the plant reducing the exhaust pressure and thereby reducing the exhaust temperature It maintains a very low back pressure on the exhaust side of the Turbine Supplies feed water to Boiler through deaerator TOP-6 BEST POWER PLANT O&M BOOKS Condenser related components: Hot well Cooling water inlet & outlet system Cooling tower Support springs or expansion neck Air Ejector system Condensate extraction system Cooling water tubes & tube sheet Vacuum breaker valve Safety valve or rapture disc Water box Air & water vent lines Types of steam condensers: Surface Co
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