Stud Welding

Arc stud welding (SW) is a welding process in which a metal fastener (weld stud) is joined to a workpiece. This process is generally referred to as stud welding. The metal fastener is joined under pressure once sufficiently heated with an electric arc. The fastener or weld stud is positioned for welding through the use of a stud gun. When the operator activates the stud gun trigger, the fastener (electrode) is welded to the workpiece without the use of filler metal. The welding duration of SW is typically one second or less.

One end of a SW fastener is prepared for welding. A ceramic ferrule surrounding the weld end of the fastener provides partial shielding of the weld. The ferrule also dams the molten metal to form a fillet type weld. Shielding gases or flux may or may not be used to protect the weld.

Typical Uses Of The Arc Stud Welding Process

The arc stud welding process lends itself to a wide range of applications such as automotive, ship building, appliance, aero-dynamics, boilers, light or heavy construction, preassembled fabrication designs and fit-up parts design. The process may be utilized on a range of material thickness from about .060 in to several inches. The stud welding process is advantageous for the following reasons:

• Major design specifications may be readily adapted to the process, such as material types, metallurgical aspects,s pecial thread designs, fit-up tolerances, etc.
  

• Capable of producing a full cross section weldment with a minimum of base metal distortion or surface disruption.
  

• Can be used in locations which do not permit use of other fastening methods.
  

• Process lends itself to the automated concept or high production shops.

• Capable of producing welds which are less costly per unit than other methods.

• Process may be effectively utilized with a minimum of time spent in personnel training.

• Process may be effectively used in maintaining weld quality with a minimum inspection time.

Stud Welding Controls

The control circuit of an arc stud welding system regulates arc duration through the welding cycle and provides adjustable controls for various stud diameters. A control circuit consists of a contractor, timing device, and current control. The weld time is a percentage of seconds or milliseconds, the current is typically depicted as amperage. Weld time is determined by stud diameter.