Apparatus for electric welding; Apparatus for mechanised welding (other than electric); Apparatus for the welding of materials; Arc welding apparatus; Electric arc welding apparatus; Electric welding apparatus; Electric wire welding apparatus, other than machines; Electrical arc welding apparatus; Metal welding apparatus (electric); Metal welding apparatus (gas); Plasma welding apparatus (gas-operated); Robotic electrical welding apparatus; Welding apparatus for tig welding (gas-operated); Welding apparatus operated by gas; Welding apparatus, gas-operated