Fuse metal together by directing huge amounts of energy into small areas.
Welds metal parts, using gas welding equipment as specified by layout, welding diagram, or work order: Positions parts in jigs or fixtures on bench or floor, or clamps parts together along layout marks. Selects torch, torch tip, filler rod and flux, according to welding chart specifications or type and thickness of metal. Connects regulator valves and hoses to oxygen and fuel gas cylinders, and welding torch. Turns regulator valves to activate flow of gases, lights torch and adjusts gas mixture and pressure, to obtain desired flame, based on knowledge of gas-welding techniques. Holds torch at proper angle to metal and guides along weld joint, applying filler rod to molten area to form weld. Examines weld for bead size and other specifications. Repairs broken or cracked metal objects, fills holes, and builds up metal parts. May apply flux to workpiece instead of filler rod. May preheat workpiece in furnace or with torch. May layout, position and tack weld workpieces. May weld along vertical or overhead weld lines. May scarf or groove weld prior to applying filler metal, using gas welding equipment. May chip or grind off excess weld, slag, or spatter [GRINDER-CHIPPER II]. May clean or degrease parts, using wire brush, portable grinder, or chemical bath. May cut metal plates or structural shapes using gas torch. May be designated according to type of gases used such as Welder, Acetylene; Welder, Oxyacetylene; Welder, Oxyhydrogen. Important variations include type of metal welded, products, subprocesses, trade name of equipment, work site, high-production or custom, level of ambidexterity required or type of joints welded. May be required to pass employer performance tests or standard tests to meet certification standards of governmental agencies or professional and technical associations.