GB1071612A - Improvements in or relating to stuffing box packings - Google Patents

Abstract

1,071,612. Stuffing-box packing. LINDE A.G. June 14, 1965 [June 18, 1964], No. 25325/64. Heading F2B. In a stuffing - box packing composed of a plurality of non-lubricated sealing rings, some at least of the sealing rings are provided with passages leading from the sealing face to the outside, through which part at least of the leakage gas can be conducted to the sealing faces of the sealing rings. Alternatively, the material of the sealing rings is porous, this porosity being a substitute for the passages. The sealing faces of the sealing rings may have transverse circumferential grooves, or circular holes, at the ends of the passages, the diameter of the holes or the width of the grooves being less than about one-third of the axial length of the sealing face of a sealing ring. The sealing face of each sealing ring may have axial grooves at the ends of the passages, these grooves connecting the passages and the transverse grooves or the holes with that side of the sealing ring at which the lower pressure exists. The side of each sealing ring at which the higher pressure exists may contain radial grooves through which a balance can be established between the pressure on the outside and the higher pressure existing at a given seal. Preferably, each sealing ring is tangentially divided and made up of several segments and has a radially-divided covering ring consisting of several segments and located so that the segments of the covering rings cover the tangential joints in the sealing ring. The sealing ring may have a supporting ring which may be radially divided. The stuffing-box shown comprises sealing carriers 35, 36 and 37 and a cavity ring 38, the carriers 35 each housing a covering ring 40, a sealing ring 41 and a supporting ring 42, the carrier 36 housing two identical throttling rings 43, the carrier 37 housing two identical sealing rings 44 while the ring 38 contains a tapping 45 to which a pipe is connected for the extraction of leakage gases. The segments of the rings are held together by closed coil springs 48 and pressed into contact with piston-rod 32. Successive sealing rings in the direction of reducing pressure are provided with passages of progressively increasing cross-sectional area or with a progressively increasing number of passages or with transverse grooves or with holes of increasing size. Alternatively, when the sealing rings are porous, successive sealing rings are of increasing porosity. In a modification, Fig. 10 (not shown), the sealing carriers are arranged in a different sequence.