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. 

Advantages

• Uniform high weld quality.
• Application on different materials.
• No blackening on other side of weld.
• No re-working necessary on the other side of the weld.
• No additional material necessary, such as flux, inert gas etc.
• Elimination of different operations such as drilling, riveting etc.
• Possible to weld studs on components with access from one side.

Applications

Capacitor discharge or Drawn Arc - How to select

Use Capacitor discharge when

• Clean welds are required
• No marking on reverse side of the weld
• Base material is thin
• For small diameter stud welding up-to 8mm
• When excellent aesthetics are required
• Only for studs with projection (pip)

Use Drawn Arc when

• High weld strength is required
• Possible on slightly oily, scaly parent material
• For structural applications
• For higher stud diameters
• For short cycle studs and drawn arc studs

The Resistance Welding Machine offered by us is widely used in various mechanical and industrial processes.