GB1191655A - Process and Apparatus for Welding of C-Shaped Workpieces - Google Patents

Abstract

1,191,655. Resistance welding. P. ESSER. [trading as MEYER, ROTH & PASTOR]. 9 June, 1967, No. 26799/67. Heading B3R. In a process for electric resistance or flash butt welding of a C-shaped workpiece 16, the latter is placed on a saddle, is centred on the saddle by upsetting tools 11, 12, Figs. 2, 3, and electrodes 18-21 grip the ends 17 of the workpiece and move them towards each other for heating up when resistance welding, or provide relative alternating movement when flash butt welding, whilst the tools 11, 12 are retracted, and then the tools 11, 12 are traversed to provide the upsetting. Tool 11 is fixed in the machine frame 10, and tool 12 can be moved relative to tool 11 by a fluid piston 13. Electrodes 18, 19, and 20, 21, are pivoted to yokes 34 and 63 respectively, the yokes being movable by fluid pressure pistons 35, 61. The grip of the electrodes is effected by pistons 22, 23, 41, 42, pistons 23 and 41 being lockable in the required position by fluid pistons 54 and 56. In operation, with the workpiece 16 on the saddle, fluid pressure is supplied to piston 14 so as to move tool 12 up to the work and centre the latter on the saddle. Pistons 22, 23, 41, 42 are actuated, and the electrodes 18-21 grip the workpiece. Pistons 54, 56 are supplied with fluid, and the pistons 23, 41 are clamped. Fluid is supplied to pistons 35, 61, through pipes 38, 65, and the yokes 34, 63 are moved towards each other until adjustable stops 39, 66 abut the frames 10, 40. Due to the workpiece being clamped by the electrodes, and also due to tool 11 being fixed, the tool 12 is moved by a distance equal to the sum of the movement of the yokes, and a gap is produced between the tools 11, 12 and the workpiece, Fig. 3. If desired the saddle may be retracted. The pressure is increased in pipe 69 to move the piston 14 in one direction when resistance welding, whilst for flash butt welding pressure in pipe 69 alternates with pressure in pipe 68, to thus provide movement in two directions. With the welding current switched on, the ends 17 of the workpiece are heated and the welding process is initiated. The upsetting is carried out by increasing the pressure in pipe 69 so as to move the piston 14 until stop 70 abuts cylinder 15. The upsetting can be effected by electrodes 18- 21 alone, by the electrodes in conjunction with tools 11, 12, or by the tools alone.