GB478845A - Improvements in joints for pipes - Google Patents

Abstract

478,845. Pipe joints. SMITH, H. P. Oct. 31, 1936, Nos. 29666/36 and 3957/37. [Class 99 (i)] In a spigot-and-socket pipe joint, the spigot is centralized and secured within the socket bv an elastic member which is applied to the spigot under tension so that its cross-section is reduced; the tension on the elastic member being relieved to effect expansion of the latter after insertion of the spigot into the socket. In the joint shown in Figs. 3 and 4, the elastic member is in the form of a ring b which is located on the spigot a, so as to form a cavity c<3> between itself and the inner end of the socket c, and is split by a tool inserted through a hole c<2> in the socket, the cavity c<3>, hole c<2> and the gap b<1> between the ends of the ring b preferably being filled with cement d. In a modification, two elastic rings are employed, the rings being either in contact with one another or else spaced to form a cement-receiving cavity. Fig. 11 shows a joint in which a length g of elastic material is lapped under tension around the spigot in one or more complete convolutions, the ends g<1>, g2 of the length being released after assembly of the parts. The elastic member may be in the form of a ring, Fig. 13, which is formed into two loops h<2>, h<3> by fixing together, e.g. by vulcanization, spaced parts h, h<1> thereof, the loop h<3> being stretched and applied to the spigot with the loop h<2> projecting outwards and the fixed parts h h<1> being released when the spigot has been inserted into the socket.