Study On Twin-Wire Indirect Arc Gas Shielded Welding

Twin-wire indirect arc gas shielded welding is a novelty welding technology, which work-piece is not linked to power source, arc is ignited and burns between the two wires, heat energy from arc column and droplets are used to melt work-piece. The advantages of this technology are large regulating range of heat input, minimum penetration ratio, high deposition rate, high usage of electric energy and low welding deformation and stress. It is a kind of welding method with high quality, high efficiency and energy conservation. It has extensive application foreground. In this paper, the welding procedure, arc characteristic and metal transfer behavior of twin-wire indirect arc gas shielded welding have been investigated systematically. The condition of stable arc burning, welding processing property, arc shape and metal transfer have been analysed by means of the automatic welding device (home-made), high-speed camera system (FASCAM Super-10KC) and oscilloscope (Aglient54624A) etc.The two wires linked to the two-pole of DC power source(NBC-350). thus the arc generates between the two wires. Different heat input leads to different melting rate, if using the same controlling systems, the melting rate of the two pole will be equal to each other, which lead to astable arc. Two different type of wire-feeding control systems were used in order to obtain the wire-feeding speed equal to the melting rate, and for obtaining stable burning arc, the two wire-feeing systems must match to each other. Results indicate that indirect arc can self-regulate, and the welding arc can burn stably in twin-wire indirect arc gas shielded welding.The welding gun is a key component of twin-wire indirect arc gas shielded welding. The structural shape and geometry dimension of welding gun not only relate to the service performance, but also relate to arc stablilyty, preservation of gas and welding quality. A special welding gun was developed. It is found that the angel of...