Stud welding is a technique similar to flash welding where a fastener or specially formed nut is welded onto another metal part, typically a base metal or substrate. The fastener can take different forms, but typically fall under threaded, unthreaded or tapped. The bolts may be automatically fed into the spot welder. Weld nuts generally have a flange with small nubs that melt to form the weld. Weld studs are used in stud welding systems. The Stud Welding Process Stud welding is a process by which a metal stud is joined to a metal workpiece by heating both parts with an arc. A key factor that differentiates stud welding from other fastening processes is that the fastener is attached to the workpiece without marring the other side. The arc stud welding method provides highly reliable fastening for a wide variety of applications. This method allows almost any size or configuration of a metal stud to be welded quickly to a workpiece, while providing maximum weld penetration and reliability.