GB1433530A - Power plants - Google Patents

Abstract

1433530 Steam turbine plant; powergenerating system BABCOCK & WILCOX CO 18 April 1973 [18 April 1972] 18672/73 Headings F1Q and FIT In a steam engine power-plant, e.g. high and lowpressure steam turbines 54, 64 for use as an auxiliary with a nuclear power-plant run at constant load, including a vapour generating unit 10 providing super-heating of the vapour at 26, 28 and re-heating at 30, and primary temperature control of the steam, e.g. by regulatable gas recirculation or water spray attemperators at 48, 58, for use during normal operation, temperature control during quick start-ups to prevent damage to the turbine by super-heated steam, is effected by attemperators 50, 60 in the super-heated steam lines 52, 62 to the high and low-pressure turbines 54, 64 supplied with saturated steam from the unit 10 via control valves 78, 86 and stop and checkvalves 80, 88. The attemperators 50, 60 each comprise a cylindrical header (51), Fig. 2, (not shown), containing a coaxial manifold (82), receiving saturated steam and discharging into the manifold through nozzles (96) opposed to entry tubes (98) from the super-heater or re-heater. The plant normally operates at constant rated temperature and pressure controlled by the attemperators 48, 58 and boiler feeding rate respectively, or with a pressure falling with load. Throttle valves 42, 46 allow the boiler pressure to be maintained constant whilst the turbine steam inlet pressure falls with load. Too low re-heat or super-heat temperature is corrected by connecting saturated steam to the condenser 68 via valve 74 to reduce the flow of steam through the super-heaters and re-heater.