GB550727A - Improvements in or relating to electric arc welding - Google Patents

Abstract

550,727. Uniting by fusion. MARTIN, H., and MUREX WELDING PROCESSES, Ltd. Aug. 22, 1941, No. 10720. [Class 83 (iv)] In automatic arc welding with a standard length electrode 1 provided with a flux coating arranged when the arc is burning to project beyond the core and engage the work to serve as a spacer for the core, the electrode is carried in a holder or trolley 3 capable of travelling by gravity down an inclined runway 4, the electrode being arranged at a steeper inclination than the runway so that the movement under gravity simultaneously maintains the arc by pressing the tip of the electrode into contact with the work and causes the top to travel along the seam. The electrode is carried in a swivelling clamp 2 angularly adjustable in the trolley and the runway is hinged at 5 to a base 6 and clamped at its slotted end by a pin 7 to the slotted end of a hinged support 10 so that the angle of inclination of the runway can be varied. The lower end of the electrode is positioned by two guides 13 extending from the runway to the support. The electrode is sufficiently rigid to act as a support for the trolley during operation. The arc continues until the electrode is used up or until the trolley engages an adjustable stop 16. The trolley when out of use is held up by a hook 14. When fillet welding lap or T-joints the runway lies in a plane inclined at 45 degrees to the vertical plane containing the length to be welded, the base 6 of the runway coinciding as in the previous case with the position at which the weld terminates. The electrode is inclined to the vertical as well as to the horizontal. When welding long seams a number of similar units of the form previously described may be erected side by side over the length of the weld and may be operated simultaneously or one may be operated while the next is being installed in position. The current may be supplied at a high voltage such as 100 volts at current density of 20,000- 30,000 amps per sq. in. of core so that the molten core of the electrode is expelled violently from the tip to leave a cup acting as an insulating spacer.