Stud welding is typically undertaken using purpose built mobile stud welding rigs, operating Nelson rectifiers and diesel generators of 250 kVa. The rig measuring approximately 7.0m long, 2.5m wide and 4.0m high will require access and hardstanding to within 7.5m of the steel frame to enable a suitable and safe earth to be obtained.

The distance between the rig and the stud welding tool is restricted to a maximum cable length of 80 metres. Where site logistics prevent access to within 7.5m of the frame, additional steel angle (approx. 50mm x 50mm) may be a possible option to provide a suitable earth.