METHOD OF COLD WELDING AND APPARATUS FOR PERFORMING THE SAME Russian patent published in 1995 - IPC

FIELD: cold welding range. SUBSTANCE: apparatus has a set of two pairs of die halves 36, 37, mounted in a frame construction on assemblies, being hydraulically driven. The die halves 36,37 of each pair may perform radial reciprocation motion for clamping or unclamping the blank 53,54 to be welded. The pairs of die halves may perform axial reciprocation motion for welding end portions of the blanks 53,54. End surfaces of the die halves, turned one to another, have nose parts 52 for removing welding flash from the blanks to be welded. Upon operation the die halves perform successive motion for clamping the blank, being welded; for moving one opposite to another and upsetting the end portions of the blanks, being welded; for unclamping the blanks, being welded, for clamping one of the blanks, being welded; for moving the blank, had been clamped, along an axis of slightly opened die halves of the second pair in order to remove the flash from the blank after each upsetting operation and maintaining a surface area of a cross section in a zone of welded seam practically constant; for secondary arranging the zone of the welded seam in a central position relative to the nose parts; for repeating the whole series of operations. Removal of the flash between the upsetting operations is being performed in changeable directions. The cutting edges 57 of the nose parts 52 may be in the form of points, in the form of a turn of a helix for increasing an efficiency of flash removing. EFFECT: enhanced quality of welded seam. 7 cl, 9 dwg