High frequency welded tube welding equipment

摘要

PURPOSE:To improve welded joint quality of a thick-wall tube by providing the specified dimensional relation and frequency on an inductor arranged for preheating the edges on this side of a V-seam weld zone of high-frequency resistance welded tube welding equipment. CONSTITUTION:At the time of arranging the inductor 11 for preheating the facing edges on this side of the V-seam weld zone on the high-frequency resistance welded tube welding equipment to form tube raw material 1 in a tubular shape having a V-shaped gap and weld continuously the facing edges of the V-shaped gap, the inductor 11 has an edge heating conductor 14 and magnetic iron cores 17 and 18 are provided on the tubular body outer and inner periphery sides of the inductor and the relation of W=S/2 (W and S denote dimensions where the outer and inner peripheral iron cores 17 and 18 lap on the one side edge and the interval between the facing edges, respectively) is maintained and electric power having =50kHz frequency is supplied to the inductor 11. By this method, the generation of spatters, oxide contamination on the weld zone and the occurrence of pinholes can be prevented and welded joint quality can be improved.