The DeltaSpot process
The defining feature of DeltaSpot is a spot welding system with continuous process tape that runs between the electrodes and the sheets being joined. The continuous onward motion of the process tape leads to an ongoing process that delivers constant quality for several production shifts in succession. This results in precision in the welding process and high electrode service life. Regular cap milling of electrodes is no longer necessary. The process tape means that electrodes are effectively protected against wear due to pick up.
The process tape transfers the welding current and, at the same time, protects the contact surfaces of the electrodes from contamination by aluminium, zinc or organic residues. The protection afforded to the electrodes gives them a significantly longer service life. Depending on the application, electrode service lives of up to 30,000 spots are thus possible. The process tape provides indirect sheet contact producing a largely spatter-free welding result. It eliminates the otherwise unavoidable rework necessary to meet new quality standards. The coating of the process tape has proved to be particularly advantageous for aluminium sheets. Optimised contact with the aluminium material prevents spattering on the sheet surface and the associated damage to components.
Due to the high electrical resistance of the process tape, during welding thermal energy is transferred from the outside to the inside. This means that for aluminium applications in particular up to 50% less energy is required, ensuring an extremely high level of efficiency compared to conventional spot welding.
DeltaSpot is primarily suitable for aluminium and steel sheets in combination with commonly used anti-corrosion coatings, which would normally result in the need to clean electrodes on a frequent basis. High quality multi-sheet joints can also be achieved thanks to the positive qualities of the process tape. The same spot welding gun can be used to weld different material combinations simply by changing the process tape.
To sum up, spot welding using “DeltaSpot” process tape can be used for a broad spectrum of applications in joining technology. Last but not least, the DeltaSpot welding process opens up new opportunities for innovation and efficiency improvements particularly in vehicle manufacturing.