GB190625100A - Improvements in Fluid-tight Joints Between Rotating Shafts and their Casings - Google Patents

Abstract

25,100. Belliss & Morcom, Jude, A., and Morcom, R. K. Nov. 7. Stuffing-boxes, substitutes for.-In packing for a rotating shaft, more particularly a steam-turbine shaft, a chamber c, Fig. 3, interposed between the casing and the atmosphere is kept at a pressure slightly above or below that of the atmosphere, and is preferably packed at each side by rubbing rings such as described in Specification No. 24,520, A.D. 1902. Fig. 3 shows two rubbing rings carried by each diaphragm d, e, making contact with a middle ring or outer rings on the shaft according to the fluctuations in pressure. In the arrangement shown in Fig. 4, the space c is packed on the high-pressure side by two rubbing ring's secured to diaphragms m, n carried by a ring situated between the casing o and a ring p on the shaft a, and consequently rotating at a reduced speed. In the modification shown in Fig. 5, a loose ring with wearing surfaces t, u is interposed between a single diaphragm-carried ring g and the casing. In a further modification, the wearing surfaces are carried by the ring g, and the loose ring is of hard material. In some cases, the rubbing surface on the casing is faced by a hard plate. The pressure in the chamber e may be maintained by a head of water, or by the apparatus shown in Fig. 9, in which the chamber c is connected by a pipe to a box x connected by pipes w<1> .... w<6> to the parts of the turbine in which different pressures occur. Each pipe contains a piston valve, acted on by the pressure, and by a spring which is adjusted to admit steam when the pressure is suitable for the chamber c. If the pressure in the pipe w<6> is below that of the atmosphere, boiler steam is admitted to the box x by a pipe controlled by a suitable valve.