FIELD: manufacture of can shells of tin plate. SUBSTANCE: method comprises steps of butt welding of can shells without wire electrode; placing welding electrodes at both side of butt welded seam; arranging electrically non-conductive roller at inner side of vessel; providing electric insulation intermediate layer between welding electrodes; continuously or intermittently cleaning electrodes. Apparatus for performing the method includes welding heads and feeding device. First head is in the form of current conductive roller with rotation drive device and two electrodes. Second head is in the form of electrically non-conductive electrode-free roller. Apparatus is provided with means for cleaning electrodes. EFFECT: reduced consumption of copper wire, enhanced sealing deg of welded joint. 14 cl, 5 dwg
