Power Generation

Main steam lines carry superheated steam from boiler to turbine at 540-565°C and 170-250 bar. Flexible wedge gate valves isolate boiler sections during startup and maintenance. Globe valves control attemperator spray water for steam temperature regulation. Chrome-moly alloy steel (WC6/WC9) handles thermal cycling without creep degradation.

Boiler feedwater pumps deliver high-pressure water to the boiler through feedwater control valves. These globe-style control valves experience severe cavitation and flashing service. Anti-cavity trim designs with multi-stage pressure let-down extend valve life. Condensate extraction pumps use check valves with low-cracking-pressure springs.

Once-through and recirculating cooling water systems use large-diameter butterfly valves (24-72 inch) for flow isolation. Rubber-lined or epoxy-coated valves resist corrosion in brackish or seawater cooling. Condenser tube bundles require isolation gates for cleaning and maintenance access.

Wet FGD scrubbers remove SO2 from boiler flue gas using limestone slurry. Slurry valves handle abrasive limestone and gypsum mixtures. Rubber-lined butterfly valves and pinch valves are common. For outlet isolation, double-lugged butterfly valves provide bubble-tight shutoff against corrosive saturated flue gas.