TWI Industrial Member Report Summary 240/1984
S A Westgate
Increased productivity can be achieved when resistance seam welding low carbon steel by increasing welding speed above the moderate speeds (2m/min) recommended in British Standard data. This work is a study of the high speed seam welding of nominally 1.2mm low carbon steel, the objectives being to establish the weldability of the material, i.e. tolerance to welding current, and to maximise welding speed when using both the conventional single phase a.c. and the more recently available three-phase secondary rectified d.c. power supplies. The effects of material composition and surface finish were also studied.
The results showed no significant difference in weldability between the two power supplies although slightly narrower welds and a fine surface disturbance were observed with d.c. Generally, welding speeds up to 6m/min could be achieved with some reliability, but up to 10m/min welding speed was achieved in isolated cases. No differences in weldability were encountered when using the two supplies over the range of material composition and surface finish studied.