GB876673A - Improvements in sealing devices for rotatable shafts - Google Patents

Abstract

876,673. Stuffing-box substitutes. HUHN, F. A. Dec. 20, 1957 [Nov. 15, 1957], No. 39609/57. Class 122 (5). A sealing device for a rotatable shaft 10, Fig. 3, such as a turbine shaft 10, comprises an annular radially divided casing 12 consisting of an end wall 13, cylindrical wall 15 and cover 20 so as to constitute at least one annular chamber 24 containing non-rotating self-lubricating sealing members 36 separated by at least one intermediate annular member 26 which is formed from a number of segments pressed axially against a shoulder 28 on the wall 15 by bolts 62, Fig. 2, in order to produce plane radial contacting surfaces for the sealing members across the points of the segments. As shown in Fig. 2, the member 26, which may be of bronze or synthetic plastic material, is provided with an annular groove 56 having a tapered lower surface 58 against which abut the corresponding tapered ends of the bolts 62 screwed into the wall 15. If desired the chamber 24 may be subdivided by two or more members 26. The sealing members 36, which may be of carbon, are each in the form of a pair of rings held in assembled position by a. pressure ring 38 engaging the conical outer surfaces of the rings so that a gap 52 separates the rings. Each sealing member with its pressure ring 38 is split into a number of segments which are held together by an enclosing member consisting of several springs 44 connected together by members 46 and, in order to limit the endwise movement of the two rings 36 under the action of the springs, the ring 38 is provided with flanges 40 engaging in slots 42 in the rings 36. The sealing rings 36 are also prevented from rotation by at least one bolt 48 screwed into the wall 15 and passing through one of the members 46 into engagement with recesses 50 in the rings. The inside surfaces 76, 78 of the wall 13 and cover 20 may be coated with a non-corrosive material, such as copper, brass, stainless steel, rubber or synthetic plastic. Cooling water may be fed to the sealing faces through a channel formed in at least one of the bolts 48 and through bores 54 in the member 26. The casing 12 may be divided into four radially separated parts corrected by bolts 18 passing through flanges 19, and in order to facilitate the installation of the member 26, which is relatively heavy, the latter may be provided with threaded holes 68 for the reception of eye bolts.