GB867318A - Improvements in or relating to seals for rotary shafts - Google Patents

Abstract

867,318. Stuffing-box substitutes. SHELL RESEARCH Ltd. Oct. 8, 1959, No. 34133/59. Class 122 (5). A seal between a ship's propeller shaft 10, Fig. II, and the stern tube 11 comprises a non- rotatable member 12 secured to the inboard end of the tube, a member 30 secured to the shaft, an intermediate member 26 located between the members 12, 30 and having a bore permitting its limited rocking movement about an axis at right angles to the shaft, a sealing- ring 29 interposed between the members 26, 30, and biasing means whereby the member 12 maintains rubbing contact with the adjacent face of the member 26. The member 12 has a flange 17 against which springs 20 act in order to urge a ring 23, which may be of leaded bronze, into contact with the member 26, which may be of stainless steel and is loosely keyed to the member 30 by studs 31; the loading of the springs is adjustable by nut-and-bolt devices 19, 22. The member 12, which is prevented from rotation by studs 33, Fig. III, passing through rubber bushes 34 in the flange 17, is formed with a sleeve 14 projecting into the stern tube and sealed by a resilient ring 16, a sheet 16a of cloth being located, if desired, between the ring and stern tube bush 11a. The bore of the intermediate member 26 may be such as to surround the shaft 10 with sufficient clearance to permit the required rocking member and preferably has the slightly convex form shown. The sealing contact faces 24, 25 of the rings 23, 26 are lubricated through passages 36 and cooled by circulating water through passages 37. The members 12, 26, 30 may be split into two parts and bolted together. In a modification (Fig. IV, not shown) a rubber sealing ring formed with grooves in its sealing face is located in the member 26 for engagement with the ring 23. At the outboard end of the shaft 10, the gland comprises a sealing ring 42, Fig. V, between a retaining ring 41 and propeller 43, and a bearing ring 44 which is screwed into the outboard end of the stern tube with an interposed sealing ring 45 and houses a rubbing ring 47 of hard rubber or plastic contacting a spring-loaded gland ring 48 located in a sleeve portion 41a of the retaining ring 41.