Patent GB-191402044-A (GB)
Title: Improvements in and relating to Fluid Pressure Turbines.
Inventor: GEORGE WESTINGHOUSE
Filed: 1914-01-26
Abstract: 2044. Westinghouse, G. May 7, 1913, [Convention date]. Void. [Published under Section 91 of the Act.] Axial - flow type ; reversing; regulating; leakage-preventing devices.- A turbine comprises an ahead and an astern section enclosed in a common casing, the valve mechanism for controlling both sections being arranged at an intermediate part of the casing, and a labyrinth packing being interposed between the valve mechanism and the rotor. The rotor is made up of end sections 3, 4, Fig. 1, carrying the shaft ends and bolted to a central drum 1. The sections 1, 4 include an impulse-wheel 2 and reaction blades 22 for the ahead section, the section 3 including an impulsewheel 9 and reaction blades 26. Blade-carrying elements 16, 19 are carried in flanges 17, 18, 20 formed in the casing. The lower portion of the casing carries a row 24 of re-directing vanes for the impulse - wheel of the ahead section, and the upper part of the casing carries a row 28 of redirecting vanes for the astern section. One member 44 of a labyrinth packing is carried on the rotor between the impulse - wheels, the other element 41 being secured to a nozzle member 30 extending completely around the inner circumference of the casing, to which it is secured by means of bolts 31, 32, the casing at this part being curved outwardly to form a steam-chest 29. The upper half of the nozzle member is composed of parts 33, 34 bolted together and carries the nozzles 45 and the regulating-valve 46 for the astern section ; the lower half of the nozzle member is similarly composed of parts 36,37 and carries the nozzles 59 and regulating-valve 58 for the ahead section. The regulating-valves are mounted on rollers 52, Fig. 3, carried on studs secured to the casing and on rollers 51 mounted on the nozzle member. The regulating-valves are operated by means of valve motors 48 actuating rods connected to the valve by a rack and pinion 49. The steam-chest for the astern section is supplied through an inlet part 60 and is divided from the steam-chest for the ahead section, which is supplied through an inlet port 61, by means of plugs 62, 63. The valves are balanced by means of steam-actuated pistons 56, Figs. 1 and 2, carried in cylinders 57 secured to the nozzle member. When the first nozzle of the astern section is opened by the valve 46, steam is admitted from the nozzle to a pipe 75, Fig. 2, to actuate a piston 72 to close a valve 69 'between the inlet 70 to the reaction blades and the exhaust 66 of the astern section, this valve being normally held open by means of a spring 76. Any steam passing the piston 72 passes through a hole 77 in the valve stem into the inlet. The exhaust passages 67, 66 of the ahead and the astern sections are separated by means of flanges 64, 65 on the casing, and the intermediate space may be packed with mineral wool. In order to utilize exhaust steam from auxiliary engines, this exhaust steam is supplied through a port 92, Fig. 1, to a space 93 between the casing and the blade - carrying elements 16, and passes through a number of ports 94 to the low-pressure portion of the ahead section. The shaft ends 7, 8 of the rotor are provided with gland packings adapted to prevent entry of air into the exhausts. A reduced portion 78, Fig. 5, of each shaft end has a sleeve 79 provided with packing- rings 83 and springs 81 adapted to engage a loose sleeve 82 forming one element of a labyrinth packing, the other element 86 being screwed to a sleeve 89 secured to the casing. Low - pressure steam is admitted through a pipe 91 to a channel 90 in communication with the centre of the labyrinth packing.