| 摘要 |
PURPOSE:To make melted resin absorbed by a chamfered part of a synthetic resin pipe to be joined and to suppress occurrence of an uneven face and a step on the inner face of the joining part by flatly cutting the edge face of the pipe, forming a tapered part at the inner peripheral edge of the edge face of the pipe, and butt welding it. CONSTITUTION:The edge face 11 of a synthetic resin pipe 1 is flatly cut by a smoothly finishing cutting blade 51 of a rotary cutter 5, and the inner peripheral edge 12 of the edge face is cut with a tapered chamfered part by an inner peripheral edge chamfering cutting blade 52. The shape of the tapered part is so regulated that the cutting angle alpha to the edge face 11 is 10 - 20 deg. and the cutting width (d) of the edge face in a direction farther than the inner periphery of the pipe becomes 0.5 - 1.5mm. Thereafter, the edge face 11 is heated and integrally butt welded. |
