Drawn Arc Welding
Drawn arc welding is a form of arc welding where the track bolt is joined using an arc. This method is also used with electrode welding. Depending on the diameter the welding time varies from 0.1 – 1.5 sec.
Contrary to capacitor discharge the weld has to be shielded from oxygen preferably using a ceramic ring or shielding gas.
Drawn Arc Welding is suitable for the following applications:
Track bolts from M6 through M24
Track bolts dia. 6 to 25 mm
Isolation pins from 3 mm
Concrete anchors (dowels) to 25 mm
The track bolt is pushed into a bolt holder in the welding gun. At the front of the pistol a ceramic ring is placed around the bolt which is then placed in the correct welding position.
The welding signal is given and the magnetic coil in the gun lifts up the bolt in the ceramic ring. An arc is drawn after which the bolt depending on the preset time is pushed into the weld. Approximately 3 mm. material is welded from the bolt, which forms a welding collar within the ceramic ring around the bolt. The ceramic ring can then be removed, and the welding is completed.
Drawn Arc Welding is applied in many industries such as ship building, bridge building and plating.