GB1250097A - - Google Patents

Abstract

1,250,097. Steam turbines. LICENTIA PATENT-VERWALTUNGS G. m. b. H. April 10, 1969 [April 10, 1968], No. 18533/69. Heading F1T. In an arrangement for cooling the connecting flanges 1a, 1b of the casing halves of a saturated or wet steam turbine to prevent inadmissible temperature gradients upon sudden reduction in turbine load, axially extending cavities 2 are provided in the flanges 1a, 1 b and connected to the rotor chamber through passages 3. During steady running of the turbine condensate collects in the cavities 2, but with a sudden reduction in load the reduction in pressure causes the collected condensate to evaporate into steam, taking up latent heat and thus cooling the outer portions of the flanges 1a, 1b to reduce thermal gradients. The steam so formed flows through passages 3 and past restrictions (9), Fig. 3 (not shown), into the rotor chamber, baffles (10) preventing the issuing steam from impinging on and damaging the rotor blades. In this arrangement the cavities 2 are sealed off from the outside by plugs (5), Fig. 2 (not shown). However in a modification, the cavities 2 are connected at 7 to pipes leading to a region of lower pressure, such as the condenser. Valves in the pipes are opened automatically or manually in the event of a sudden reduction in turbine load, thus allowing steam to flow from the rotor chamber through passages 3, cavities 2 and the pipes to the condenser to cool the outer portions of the flanges 1a, 1b.