GB210456A - Improvements in and relating to steam turbines for working with steam of high pressures and high degrees of superheat - Google Patents

Abstract

210,456. Akt.-Ges. Brown, Boverie, et Cie. Jan. 29, 1923, [Convention date]. Motor power plant; transmission mechanism ; bearings ; balancing end-thrust.-In a compound turbine using steam at very high initial pressure and superheat, the high-pressure stage turbines are arranged to have small individual heat-drops as described in Specification 196,913, and their rotors are mounted in an overhung manner on pinion shafts which are disposed symmetrically around the main gear-wheel on the shaft of the low-pressure stage turbine or on the shaft of a dynamo. When two high-pressure stages are used they are disposed diametrically opposite one another in a horizontal plane. Fig. 2 shows two high-pressure stages a<1>, a<4> in series driving a main overhung wheel i. The casings are secured by flanges to the gear box and centering wedges or keys arranged crosswise are employed to locate the casings and permit expansion. The casings may be divided longitudinally in a plane inclined at 45‹ to the horizontal to facilitate access to the flange bolts. Four high-pressure stages may be disposed in pairs at opposite ends of a dynamo or low-pressure stage turbine. The axial pressure of the single-helical gears may be balanced by the end thrust of the steam-pressure on the shattless ends of the turbine rotors and the angle of the teeth may be chosen for this purpose. Fig. 4 shows a construction with the pinion bearings c, d and the labyrinth stuffing box s mounted in a common casting which is supported in bores u in the gear-box. Water is admitted to a groove q for cooling the shaft and the latter is equipped with oil and water deflecting rings r. Steam leaking through the gland s passes away at w and a passage z extracts any steam leading into the joint y.