GB714705A - Improvements in and relating to steam turbine plants - Google Patents

Abstract

In steam turbine plants wherein part of the water of condensation is cooled and is then sprayed into the exhaust chest of the turbine in order to condense the exhaust steam by direct contact, the casing of the turbine at its discharge side is extended by a conical annular diffuser which penetrates into the exhaust chest. The cooled condensate is in part sprayed into the exhaust chest through nozzles which direct it in jets against a wall of the diffuser. In the Fig., the rotor 2 of the turbine with its shaft is supported in bearing 3 surrounded by the wall of exhaust chest 4. Cool water is sprayed into the exhaust chest through nozzles in boxes 43 and 44; and the condensate and coolant are collected in receptacle 5. Pump 7 withdraws part of the water from receptacle 5 and forces it through cooler 9. The remainder of the water is continuously withdrawn from receptacle 5 as feed-water. The cooled water (from cooler 9) is pumped through conduits 10, 101 and 102 to boxes 43 and 44. Stuffing box 28 for the rotor shaft is sealed by water of condensation, which is carried along by the shaft and atomized in exhaust chest 4, wherein it furthers the condensation of the exhaust steam. Box 43 is provided with nozzles facing the conical outer wall of diffuser 42. The boundary layer of steam in the diffuser is withdrawn, not only by cooling, but also by suction via circumferential slots 45 in the diffuser walls and via chambers 46 and <PICT:0714705/III/1> 47; both chambers being connected to injector 48 which is operated by water from box 44. The water discharged by the injector is distributed by perforated partition 49, so that it also serves for condensing exhaust steam from the turbine.