| 摘要 |
PROBLEM TO BE SOLVED: To provide an electric-resistance weld pipe welding device capable of having a high heating efficiency.SOLUTION: A first induction coil 3 positioned the closest to a junction 6 is an air-cored coil, and is so arranged over an opening 2 without circulating the outer circumference of an open tube 1 that a primary current circuit may be formed across an opening 2. By feeding a high-frequency electric current to the first induction coil 3, therefore, an induction current flows concentratedly in end face parts 2a and 2b thereby to heat the end face parts 2a and 2b efficiently. In other words, it is possible to acquire a high heating efficiency. |
