GB1339834A - Water-cooled electrical machine - Google Patents

Abstract

1339834 Rotary shaft seals KRAFTWERK UNION AG 19 April 1971 [4 April 1970] 27303/71 Heading F2B [Also in Divisions F3- F4] Apparatus for circulating cooling water through cooling ducts 5a, 5b in the rotor 3 of an electrical machine, e.g. the generator portion of a turbo-generator, comprises a fixed head 9 having water supply and return chambers K1, K3 which co-operate with a shaft 3b of the rotor in a fluid-tight manner and a further leakage water chamber K5 is provided adjacent the outlet chamber K3 with shaft sealing elements w2, w3 operating without physical contact with the rotor shaft. The leakage water passes from chamber K3 to the chamber K5 through a shaft sealing element w2 therebetween and thence through an aperture 12 into a collecting chamber 13 below the head 9. The cooling water thereafter passes into a circulation system comprising a pump 16, a filter F, for removing air inclusions and dissolved undesirable constituents, a water cooler W, an oxygen remover 15 and a water accumulator 11 wherein the water is saturated with hydrogen gas and means for maintaining a hydrogen excess in the water flowing to the oxygen remover 15. The head 9 has a pump 7 driven by the shaft of the rotor to deliver cooling water returned to the suction chamber K2 to the inlet chamber K1 and the oxygen remover includes a palladium catalyst. In a modification, Fig. 2a, not shown, a pressure compensation chamber (K4) is provided between the chambers K3 and K5 which has shaft sealing elements operating without physical contact with the rotor shaft. The chamber (K4) is filled with water at a pressure intermediate that in chambers K3 and K5 and is connected by a conduit to the water in the water accumulator. A gas suction chamber (K6) may also be provided. The shaft sealing elements may comprise water-ring stuffing boxes or labyrinthine elements with a radial gap.