Improving the Competitiveness: of the European Steel Fabrication Industry Using Synchronised Tandem Wire Welding Technology

The SYNFAB project has delivered improved MAG welding technology to the fabrication industry, which enables higher deposition rates, deeper penetration and reduced fabrication costs, without compromising weld properties. What is more, SYNFAB demonstrates how this may be achieved without the need to invest in expensive and specialist welding equipment. Two generic types of tandem MAG welding were identified. The first with arc spacing of approximately 6 mm, a design on which most commercially available synchronised tandem MAG welding equipment is based; and the second with arc spacing above 10 mm, which had not previously been identified. With spacing below 10 mm, synchronisation of pulses was required, otherwise the arcs would interact and become unstable. However, when arc separation exceeded 10 mm, there was much more flexibility to use a variety of arc types. Three types of joint were evaluated: a lap joint using 3 mm steel, a fillet joint using 6 mm steel and a double-sided butt joint using 12 mm steel. In all cases tandem welding enabled a significant increase in welding speed whilst maintaining good weld quality.