VALVE INTERPOSED IN RESIN PIPE LINE WITHOUT INTERRUPTION OF FLUID

PROBLEM TO BE SOLVED: To provide a valve safely and easily interposed in an existing resin pipe line without interrupting a fluid. SOLUTION: This valve 1 comprises a cylindrical valve box 3 containing a valve element 2, sleeve pipes 4A and 4B protruded from both the end ports of the valve box 3, and resin-made sockets 5 and 5 having the sleeve pipes 4A and 4B fitted thereto and integrally assembled to the valve box 3 while retaining the airtightness or liquid-tightness between the sleeve pipes 4A and 4B and the valve box 3. Each of the sockets 5 and 5 is formed of an assembly of two socket pieces 50 and 51 thermally fused in halved surfaces 6 and 6 by carrying a current to a fusing heating wire 51E. The cut end parts 7A and 7B of the existing pipe line 7 are fitted to the respective opposite sides to the sleeve pipes 4A and 4B of the sockets 5 and 5, and thermally fused and integrally connected to the socket 5 and 5 by carrying a current to a spirally wound fusing heating wire 52.