Studies On Gas-powder Mixture Shielding Arc Welding

CO₂ arc welding which is a high efficient weld technique is widely used in the weld of mild steel, low alloy steel and other black metals or the weld in different thickness and position because of its merits of high productivity and wide use in manufacturing production. On the other hand, this technique has two shortages of large quantity of spatter and formation of weld.The gas-powder-mixed CO₂ arc welding technique was developed in this dissertation. By adding active fluxes in the course of arc burning, weld melt and formation, many good qualities,such as low spatter and formation of weld will be obtained. And in the same time, conformable alloy will also formed.A new apparatus was designed in the thesis, which is consist of a rolling wheel, a revising device,a carved wheel and a delver powder device.Through two rolling wheels in different position, weld was rolled to be dented one which can be filled with powder, and the surface burr on weld can be wiped off by rolling wheels. All active fluxes can be brought to weld section by a delver powder device. Combination of weld and active powder was very alterable and multi-using by all above devices.The technics performance of gas-powder-mixed CO₂ arc welding was studied via the contrast experiment of ordinary H08Mn2SiA weld with active fluxes and ordinary H08Mn2SiA weld. Experimental results show that rate of spatter will descend by gas-powder-mixed CO₂ arc welding technics, but the penetration, width, and ratio of width/depth will increase.. Weld shapes will change as the result. So, the surface of weld slot was shaped well. .Melting drops are transferred by fine granule with gas-powder-mixed CO₂ arc welding technics according to middling standard parameters.