This is a fast and economical method of welding studs of various shapes and diameters onto the parent material. Stud welding is used for fixing studs onto the parent material without making holes. Normally for fixing studs and fasteners, you will have to adopt operations such as drilling and tapping. By using stud welding you can completely avoid these operations.
There are two main methods of stud welding i.e. Capacitor discharge stud welding and Drawn Arc stud welding. The selection of the process depends on thickness of the parent material, diameter of the stud, weld strength required and welding aesthetics requirement. The capacitor discharge method is used for thinner material and drawn arc method is used for higher diameter studs and heavy parent material.
Capacitor Discharge Stud Welding
In this method a small projection (pip) at the end of the stud makes contact with the work-piece and energy from the bank of charged capacitors is discharged across the contact, melting the stud projection and creating shallow molten pool in the parent plate. At this time the stud is pushed into the work-piece under controlled spring pressure, completing the weld. Energy required for given welding operation is obtained by selection of voltage across the capacitor.
This process minimizes the depth of penetration into the parent metal surface and is used for welding smaller diameter ferrous and non-ferrous studs on light gauge material. The stud can be welded on the reverse side of coated or finished sheet with little or no marking on the finished side.
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