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Showing posts with the label steam turbine

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


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