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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

Why do the Boilers explode???

  Now days, we are hearing more on explosion in Boilers & related auxiliaries. This is harming man, machines & system and creating unrecoverable situations in power plant. Upon thinking on this following major causes or reasons come into picture. The main reasons for Boiler explosions are; Operating the Boiler more than the design pressure for long time Operating the Boilers at lower water level in drum High furnace pressure Poor water quality Poor maintenance of Boilers in shutdowns Ignoring the aging factors of Boiler parts Operating the Boilers at higher main steam or metal temperature Power plant safety Questions & Answers Viva Questions & answers for preparation of BOE exam & interview 1-What are the reasons for operating the Boilers at more than operating pressure? Malfunction of pressure transmitter or leakages in its impulse line Faulty local pressure gauges Faulty safety valves or safety valves set at higher pressure Improper control of

Protections & Interlocks in power plants

 Interlocks:   Are the programmed or hardwired control systems to protect systems and improve the operation reliability. Protections: Are the programmed or hardwired control systems to protect the equipments, man power and systems from failure/harm. The interlock and protection system is used to ensure safety of equipment and personnel as well as smooth & trouble free operation of the plant This system initiates automatic corrective actions to stabilize the unit quickly. The protection scheme is developed to trip the equipment automatically with or Class A trip involves a serious electrical fault like differential, stator earth fault etc. and is considered to be the most dangerous in terms of the shock on the unit. Since it involves serious electrical faults, connections from both generator and the HV bus is immediately switched off to limit the damage at the fault point and also to isolate the healthy system. Hence the unit (turbine, generator and boiler) has to be tripped
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