GB295575A - Improvements relating to the working of steam power plants involving long pipe lines - Google Patents

Abstract

295,575. Akt.-Ges. der Maschinenfabriken Escher, Wyss, et Cie. Aug. 13, 1927, [Convention date]. Automatic gear.-A steam-power plant supplying steam for auxiliary purposes through a long pipe to the place of consumption is so controlled that when the steam consumed is varied, the pressure of steam taken from the engine is sc varied that the pressure of steam where consumed is approximately constant. The change in the back or bleed-steam pressure may be obtained by varying the steam passing through the engine in dependence on the steam pressure in the vicinity of the consumer. The steam passing through the engine may also depend upon the pressure directly behind the engine or on the pressure at the tapping-point. The steam supply may also be varied by the quantity of steam passing to the consumer and by the pressure therein or by the back or bleeder pressure immediately behind the engine. In the construction of bleeder steam turbine driving a generator G shown in Fig. 1, the supply depends upon the pressure at 7 adjacent the consumer V which affects the line steam valve 1 of the high-pressure element H. Steam tapped at 4 passes through a long main 5 wherein considerable pressure drop occurs to the consumer V. A governor-controlled bye-pass 2 is placed between the stages H, N. In a modification, the turbine exhaust supplies the consumer. The pressure adjacent the engine and a velocityoperated Venturi-meter control the valve 1. In the construction shown in Fig. 3, the turbine supply valve 1 is controlled by the pressure at the consumer in pipe 10, and by the pressure at a point 11 behind the, engine. The pressure at 10 controls a switch 13 which affects a motor 14 supplied from a source 15. The pressure at 11 affects a diaphragm 26 and thereby a lever 16 which carries a plate 17 controlling a nozzle 18 of a fluid-pressure chamber 19 the pressure in which affects the valve 1. The motor 14 through gearing 23, 24 regulates the spring 25 acting on the lever 16.