FORMING AND WELDING METHOD OF THICK-WALLED ELECTRIC WELDED STEEL PIPE

• Main Authors: TERASAWA TAKESHI, MIZUTANI WATARU
• Format: Patent
• Language: English
• Published: 08.11.1984
• Subjects: CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR; PERFORMING OPERATIONS; SOLDERING OR UNSOLDERING; TRANSPORTING; WELDING; WORKING BY LASER BEAM

PURPOSE:To heat uniformly butt end faces in a weld zone and to produce a thick-walled steel pipe in the stage of forming and welding the thick-walled electric welded steel pipe by inserting two separated insulators into the central part at the butt end faces of the butt parts of the steel pipe and welding the same. CONSTITUTION:Wedge-shaped insulators 7, 7 which are divided to above and below so as to form a gap 8 at the center 4 of the butt end faces in butt parts 3 of a thick-walled steel strip are inserted into the parts 3 and the tips of the insulators 7, 7 are kept always pressed to a weld point 5. High-frequency electric current is conducted to the weld point 5 at the tip of the butt parts by an electrode 16 for high frequency current, by which the point 5 is heated to melt. The molten part is joined by press contact with squeeze rolls 2, by which a pipe 1 is formed.