For stud welding with an arc, four methods have established themselves as the most common welding methods. The right procedure and correct parameters are important for all common stud sizes and materials. Non-ferrous metals or special shapes can be processed with this welding process with consistent quality.
Arc joint welding for all types of bolts
The general process for welding studs is arc fusion welding. With this method, the bolt is initially held at a small distance from the base material after it has been placed. When the welding current is switched on, an arc is created which generates a high temperature on the underside of the stud and the contact point with the base material. This temperature causes both points to melt and the so-called "weld pool" is created. The bolt is pressed into the base material, which is also liquefied, with the underside melted. The materials mix with one another and solidify. This completes the welding process and ensures the permanent connection between the stud and the base material. To support the arc and to deoxidize the weld pool, the underside of larger studs is equipped with a small aluminum ball as a filler material.
Method 1: Stud welding with shielding gas
With inert gas welding, the stud is completely covered with a sleeve. The shielding gas is introduced into this sleeve before fusion welding. This displaces the oxygen at the welding point and thus ensures that the materials cannot oxidize during welding. The potentially existing residual oxygen is consumed by the filler metal on the underside of the bolt. The steels or non-ferrous metals of the bolts and base material can liquefy without burning. The inert gas introduced ensures a clean welded joint.
Method 2: stud welding with tip ignition
Welding with tip ignition is carried out with special studs with a shaped tip. A distinction is made between welding "with a gap" and "without a gap". Tip ignition welding is suitable for studs with a maximum diameter of 8 millimeters. The materials used for this welding process are steels and non-ferrous metals. Welding with tip ignition is very fast at 1-3 milliseconds. It is therefore particularly suitable for the serial processing of thin sheet metal. Due to the low wall thickness of the processed steels or non-ferrous metals and the fast processing time, welding with tip ignition manages without weld pool protection.
Method 3: short-term stud welding
As an alternative to welding with tip ignition, short-time stud welding is also available for cylindrical welding studs up to a maximum of 12 mm in diameter. At 5-100 milliseconds, this welding process is somewhat slower than stud welding with tip ignition. But it's still very fast. With these fast processes, aluminum is not required as a filler material. This form of stud welding is suitable for manual arc welding as well as for serial and automated welding processes. Precise monitoring of the welding parameters is necessary for consistent fusion welding quality.
Method 4: Build-up welding with studs
Welding studs can also be used to efficiently fill in unwanted holes in the base material. It is not as effective as normal build-up welding, but it may be sufficient under certain circumstances. To do this, the hole is drilled to match the stud diameter and the welding stud is set. After the bolt has been set, the protrusion is ground off and, if necessary, filled with solder as a filler material. This fusion welding is only suitable for cosmetic corrections.