The use of the capacitor discharge welding process is highly effective for welding fasteners onto metals. It is most often used with mild steel and stainless steel in construction and building, but it can also be used with titanium, copper, brass and aluminum.
The process of capacitor discharge welding is designed to be very effective and quick, adding both efficiency and cost-savings to any project. Using this method, a single stud can be welded in place on the workpiece in 0.004 seconds and the process can be perfectly repeated time and time again through the equipment in use today.
The system uses a bank of capacitors that store energy. The specific voltage that will be supplied to the gun is based on the size of the stud as well as the material of the stud and the workpiece.
The stud is held in the gun with the ignition tip, a protrusion at the base of the stud, just above the workpiece. The ignition tip and the workpiece are joined through an arc created when the weld is initiated. This ignition tip melts, as does the corresponding surface of the workpiece. This process takes about 0.002 of a second.
At that time the gun forces the stud down into the molten metal where it permanently bonds. Immediately the gun is removed and the stud is permanently in place. This can be done manually or with automated systems that are used for high volume types of jobs.
Ideally, capacitor discharge welding can be used with any type of workpiece suitable or the process. However, it is often considered the best option for think workpieces where the very short exposure time to the arc does not create any discoloration or blemishing on the other side of the metal.