| 摘要 |
PURPOSE:To bond pipe bodies so as not to produce difference in level in the inner surfaces thereof by arranging two pipe bodies at the position where the end surfaces thereof are mutually opposed to arranged a core body to the inner surfaces of the opposed parts thereof and melting the end surfaces of the pipe bodies under heating to subject the same to butt welding. CONSTITUTION:In bonding two pipe bodies made of a synthetic resin used in clean piping for transporting ultrapure water, two pipe bodies 1, 2 are arranged at the position where the end surfaces 6, 7 thereof are mutually opposed and a core body 4 having a diameter smaller than that of the pipe bodies 1, 2 is arranged to the inner surfaces of the opposed parts 8, 9 thereof. Subsequently, the end surfaces 6, 7 of the pipe bodies 1, 2 are heated and melted by a heater 3 to be mutually subjected to butt welding. At this time, since the weld beads generated in the inner surfaces of the opposed parts are pressed by the outer peripheral surface of the core body 4, the smooth weld bead surfaces are formed to the inner surfaces of the pipe bodies 1, 2. After butt welding, the core body 4 is detached. As the core body 4, a shape memory alloy is used if necessary and the insertion and detachment of the core body are made easy. |
