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Showing posts from April 28, 2020

BOILER DRUM LEVEL CONTROL SYSTEM

Boiler is the heat source of steam for the turbine. In boiler water is a cooling medium in the boiler pressure part by absorbing the the heat.  If too little water is available in the boiler then inadequate cooling of metal parts and chance of damage to the pressure parts. If too much water is supplied to the boiler then steam can carry the water or water particles to the turbine & causes turbine damage. In boiler amount of water and levels are controlled by a station called as Feed Regulating Station (FRS) or Feed Control Station (FCS) . In FRS/FCS there are three control valves, which is arranged in parallel. In it two valves can handle 100% BMCR load and one can handle 30% BMCR load. Two valves of 100% are provided for redundancy. 30% capacity used for startup and shutdown condition. Each control valve consist its own motorized isolation valve. If feed water flow is not controlled by a single valve then any of 100% valve can operate with 30% valve. Both 100%