HIGH-SPEED REMOVING METHOD OF REINFORCEMENT OF WELD BEAD OF ELECTRIC RESISTANCE WELDED STEEL TUBE

摘要

PURPOSE:To remove the reinforcement of weld of beads at a high speed with a contactless type and eliminate the lowering of quality of a weld zone by remelting electric resistance welding beads by using a laser beam and blowing gas at a specific flow velocity. CONSTITUTION:The weld beads respectively formed on the inside and outside surfaces of a steel tube 8 right behind an electric resistance welding point 2 are irradiated with a high-output laser beam induced through an optical fiber transmission cable 1, by which the weld bead are heated and remelted. The laser beam to be used for irradiation is adjusted to have output of >=0.5kW. The gaseous flow of the inert gas or gaseous nitrogen part respective gas carrier cables 3 is blown at a flow velocity of >=1.5liter/min.cm<2> to the remelted beads 6 on the inside and outside surfaces of the steel tube 8 and the beads are removed from the positions on the weld line. For example, the remelted beads 6 splash in the form of granular drops 7 and solidify immediately.The solidified beads are discharged without adhering to the steel tube 8.