GB747920A - Improvements relating to fusion welding - Google Patents

Abstract

747,920. Welding by fusion. LINCOLN ELECTRIC CO. Nov. 11, 1953 [Nov. 12, 1952], No. 31308/53. Class 83 (4). [Also in Group XXX] In fusion welding apparatus including a hopper for granular flux having a nozzle through which flux can escape under gravity, means are provided for drawing air through the nozzle to prevent escape of flux therefrom. In one embodiment a welding head A, Fig. 1, is supported on a trolley B by a flexible tubular support 14. One or more electrodes 31 are fed from a reel 53 to the head through a conduit 50 within a corrugated hose 60 connected to a suction pump 61. The conduit 50 terminates in a nozzle 30, Fig. 2, located within a fibre suction nozzle 33 with a metal extension 39. A flux hopper 20 of larger diameter than the nozzle 33 and of reinforced corrugated tubing is secured at one end to the nozzle 33 and at the other end to funnel-shaped members 65 which are connected to the hose 60. A filter is arranged between the funnels and a butterfly valve 72 controlled by a solenoid is provided in the hose. In operation with the pump running and the valve open, the nozzle 33 is inserted in a flux container and flux is sucked up to fill the hopper. The flux is not carried beyond the hopper since in the enlargement provided by the funnels the air velocity is decreased and the flux grains fall back into the hopper. The head may now be moved to the workpiece, suction keeping the flux in the hopper. The valve 72 is closed and flux pours from the nozzle, the electrode feed is started and submerged arc welding is commenced. To remove unfused flux after welding the head, with suction applied, may be moved over the seam. The funnels may be replaced by a centrifugal separator, baffles, &c. In a modification, a tube 80, Fig. 5, branches from the hopper 20 at a point below the funnels and extends to a position level with the nozzle 33. In operation with the hopper filled, the valve 72 remains open and air is drawn through the branch to weaken the suction on the flux in the hopper which falls on to the work. Flux remaining on the seam is sucked up by the branch tube and returned to the hopper. When the hopper is empty the nozzle 33 and branch tube are placed in a flux container and when the hopper is filled the tube 80 is closed by hand or by a valve so that full suction is applied to the hopper to prevent escape of flux until the tube is opened. A suction head without an electrode fed therethrough, Fig. 6 (not shown), may be used with other torches. A non- portable apparatus includes a wheeled carriage movable along a track and supports a head comprising a large flux hopper through which is fed an electrode wire. Specification 648,638 is referred to.