摘要 |
The invention relates to pipe couplings and particularly to apparatus for connecting adjacent ends of plastics pipes, the connection of fittings to pipe ends, or the connection together of pipe fittings. Plastics pipes and fittings are in common use. In the critical area of the supply of gas it is traditionally so that pipe ends and fittings are fusion-welded, by butt fusion or by electrofusion techniques. In the not so sensitive areas of water supply and electricity and telecommunication fields, the connection of plastics pipes and fittings is not so critical, albeit that a good joint is required. This has led to the creation of so-called spin welding techniques where a coupling sleeve (15) is caused to rotate around a pipe end/fitting (1) with friction melting of the interface which, on cooling, creates a weld. The object of the invention is to provide apparatus that is simple and effective, an objective that is met by a construction comprising drive mechanism adapted to engage the coupling sleeve and impart a rotary motion thereto, said drive mechanism being further adapted to apply a radially inward force to said coupling sleeve, whereby to ensure contact between said coupling sleeve and the pipe end(s)/fitting(s) during rotation of the sleeve. |