| 摘要 |
Two pipes are connected together by insertion of a spigot end of one 1, coated at least externally with a thermoplastic synthetic material 6, into the socket end 3 of the other, coated at least internally with the thermoplastic material 7, a sleeve-like perforated packing member 8 of heat conductive material being positioned between the spigot and socket ends, so that a joint can be made by applying heat to the exposed end of the sleeve, causing the thermoplastic material to flow in the perforations. The sleeve extends over the socket end in the form of a cap and over the end surface of the spigot end; control perforations 11 at the outer end indicate when the thermoplastic material has flowed to form the joint. The sleeve is frusto-conical externally and is provided with annular teeth 12 opposing opening of the joint. <IMAGE> |
