Abstract: Apparatus for resistance welding an elongate seam in a tubular article, comprises a first electrode wheel outside the article, a second electrode inside the article and a continuous electrode wire arranged to pass over the electrodes to provide surfaces of contact between the electrodes and seam material. The second electrode has a stationary block having a guide surface of like curvature to that of the outer electrode wheel so that the contact arcs of wire passing over the guide surface with the seam material is substantially equal to the contact area of wire passing over the external wheel. The use of this stationary inner electrode improves the weld of geometry and permits welding of can bodies of relatively smaller diameter without use of mercury contact bearings.