GB196969A - Improvements in and relating to packings for rotating bodies - Google Patents

Abstract

196,969. Parsons, Sir C. A., and Carnegie, A. Q. Jan. 3, 1922. Stuffing-boxes, substitutes for. - Packing of the type described in Specification 12347/01, [Class 110, Rotary engines &c.], in which knife-edges cooperate with plane surfaces, is modified by arranging the plane surfaces with which successive knife edges cooperate out of alignment. As applied to shaft packing collars c, Fig. 2, on the shaft are formed with stepped surfaces d co-operating with knife-edges h on collars g carried by the casing, or vice versa. The steps d may be perpendicular to the shaft, or undercut, as shown. Alternatively, the collars c may be formed with projecting flanges, the knife edges co-operating alternately with the flanges and with the recesses between the flanges. As applied to packing for turbine blades, the steps may be formed wholly on the spacing pieces n, Fig. 5, between the blades, or may be formed partly or wholly on strips o inserted in the blade grooves, or partly by collars p, Fig. 7, on the rotor and stator. The knife edges h, Fig. 5, may be formed on the edges of two or more independent shroudings q, or a single shrouding may be formed with a terminal knife edge and a flange, approximately at right-angles to the body of the shrouding, carrying one or more additional knife edges. In the modification shown in Fig. 7 the shrouding q is of U section, each limb being formed with a knife edge h. Stiffeners may be arranged in the bend of the U, or the tenons r of the blades may be prolonged to support the outer limb of the U. Preferably in all forms of the packing means are provided for adjusting the axial clearance. Specification 8547/05 also is referred to.