TWI Industrial Member Report Summary 745/2002
S J Mulligan and G B Melton
In today's economic climate, fabricators are increasingly under pressure to reduce costs and substantial benefit can be achieved by increasing productivity. One of the most versatile arc welding processes is MIG/MAG welding, and in recent years, there have been a number of process developments to enhance deposition rate, and hence productivity. Developments in welding equipment and shielding gases have led to substantial claims for process improvement for a single wire with high wire feed speed, high current and stable metal transfer. This has been achieved by using extended contact tip to workpiece distance, waveform control and four component shielding gases.
Developments in inverter power sources and electronic control systems have recently led to new process developments with two wires fed through one torch. One variant on these developments, the tandem MIG/MAG process, with independent control over each wire, is the subject of this report. This process is suitable for mechanised welding only, and the main potential advantages are claimed to be increased deposition rate and faster travel speeds.
- Review the development and applications of the tandem MIG/MAG process
- Determine the capabilities of the process to achieve increased productivity through higher deposition rate and travel speed.