摘要:
In mash seam welding for performing to weld metal plates with thicknesses of 2 mm or more, it is possible to stabilize the strength of a joint portion, reduce uneven parts of the joint portion, ensure high strength and reliability of the joint portion, and join metal plates with thicknesses of 4.5 mm or more. Two metal plates (5, 6) are clamped with first and second clamping devices (7, 8), and the two metal plates (5, 6) are placed to overlap each other at their end portions, and then overlapping portions (L) of the two metal plates 5, 6) are pressed with a pair of upper and lower electrode wheels (1, 2) while welding currents flow to continuously weld the overlapping portions (L) and join the two metal plates. The pessing forces applied to the upper and lower electrode wheels (1, 2) are controlled so that upper and lower welding forces acting upon the overlapping portions are equal to each other during the time when the overlapping portions are continuously welded while the welding currents flow.
摘要:
When metal plates each having a thickness smaller than a diameter of each of shoulders of rotary tools are joined by both-side friction stir welding, rupture and defective joining of the metal plates are suppressed, joining strength is enhanced, and reliability of the joining strength is improved, while the tool life is prolonged and the rotary tool economy is improved. Inlet and outlet side gripping devices 7, 8 grip front and back surfaces of metal plates 1, 2, respectively, and rotary tools 5, 6 disposed in opposed relationship in the front surface side and the back surface side of the welding portion J are moved in a direction in which the upper and lower rotary tools approach to each other and impart a predetermined clearance ´ between distal ends of probes 13a, 13b of the upper and lower rotary tools 5, 6 while pressing the shoulders 5b, 6b thereof against the front and back surface sides of the welding portion J. Under this state, the upper and lower rotary tools 5, 6 are moved along the butting portion J while rotating the upper and lower rotary tools thereby to perform the friction stir welding. At this time, the axes 14 of the upper and lower rotary tools 5, 6 are inclined in a direction in which the respective probes 13a, 13b move ahead of the other portions of the rotary tools with respect to a traveling direction of the rotary tools 5, 6.
摘要:
A pair of upper and lower pressure rollers (3, 4) is disposed so that their axes (15, 16) are tilted in a horizontal plane in respective directions opposite to each other with respect to a straight line perpendicular to a welding line of a joint portion J. The pressure rollers (3, 4) are positively driven by corresponding electric motors (63, 64) to thereby roll the joint portion. Thus, steps defined at the joint portion can be smoothed and a step gradient can be reduced to ensure a high degree of joint strength. The respective tilting directions of the axes (15, 16) of the pressure rollers (3, 4) are such that respective travel-directional portions (3A, 4A) of the pair of pressure rollers (3, 4) face in the horizontal plane toward the corresponding directions opposite to the extending directions of metal plates (5, 6) concerning a metal material with which the pressure rollers (3, 4) first come into contact. Thus, it is possible to prevent a step portion from being interfolded into the base material of the metal plates (5, 6). Thus, a stress concentration factor can be reduced and the steps S defined at the joint portion can be smoothed, thereby enhancing the quality of the joint portion.