It may be a challenge to determine if capacitor discharge (CD) or drawn arc welding is the best option for a given project. While they are similar in some aspects, they are also very different processes, ideally suited to specific outcomes, processes, and types of applications.
The similarity between the two processes is the ability to use a quick, effective and consistent way to fasten the capacitor discharge studs or the drawn arc studs to the base piece of metal without the need to drill holes and to have access to the other side of the base piece.
Drawn Arc Stud Welding
Drawn arc stud welding uses current, either AC or DC, to develop an arc which is used to melt the end of the drawn arc weld stud and a small area of the base metal to create a solid weld. The drawn arc weld gun pushes the weld stud into this molten pool and, with the use of a ceramic ferrule around the area, the molten material is held in place and the ferrule provides a shield until the weld cools.
As the process is ideal for larger diameter weld studs, it is typically used on heavy base pieces and larger projects such as shipbuilding, bridge deck construction and building construction.
CD Welding
With the CD welding process, the same basic mechanism occurs, but the current is created with a capacitor storage system that releases the energy. There are both contact and gap welding options to use with capacitor discharge studs, which are smaller in diameter and used with thinner base metals.
As this is a faster process, with welding completed in fractions of a second, there is no discoloration or twisting, buckling or dimpling of even thin base pieces of metal.
The choice of capacitor discharge studs and CD welding is ideal for electronic components, metal cabinets and doors, HVAC system components and with jewelry and the production of cookware and utensils.
