METHOD FOR MOLDING ELECTRO-RESISTANCE-WELDED TUBE

• Main Author: HAYASHI TOMOTAKA
• Format: Patent
• Language: English
• Published: 17.03.1992
• Subjects: AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKINGWITHOUT ESSENTIALLY REMOVING MATERIAL; MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES,OTHERWISE THAN BY ROLLING; MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVINGMATERIAL; PERFORMING OPERATIONS; PUNCHING METAL; TRANSPORTING; WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS ORPROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL

PURPOSE:To eliminate the difference in the stretching rates of an edge part and bottom part and to mold an electro-resistance-welded tube without edge buckling by combining tension impartation and bottom part rolling by using a roll molding machine. CONSTITUTION:The material in the vicinity of the bottom part is rolled down under the application of tension, by which the compressive force, i.e., the force tending to shrink the edge part is not acted in the edge part and the length in the edge part and the bottom part is made the same and, therefore, all the causes to generate the edge buckling between stands are eliminated. Since the tension in a fin pass is decreased, the generation of roll flaws is decreased as far as possible.