Getting straight to the point Cost-effective joining of aluminum sheets with resistance spot welding

Whether in the automotive and supplier industry or in the aerospace industry, if you want to join aluminum sheets, there is no getting away from resistance spot welding. This special process delivers impressive energy efficiency, low component distortion, high productivity, and does not require any filler material whatsoever. Fronius offers a range of suitable solutions for resistance spot welding: From the new DeltaCon guns for conventional spot welding to the innovative DeltaSpot system, which has revolutionized the welding process with its continuous process tape.

Perfect welding results “spot by spot”. There’s simply no other way to describe the DeltaSpot system from Fronius Perfect Welding. The resistance spot welding process is not only suitable for aluminum and steel, but also for other materials, and is mainly used for demanding sheet metal joints. The continuous process tape, which runs between the electrodes and the sheets to be joined, is the system’s most characteristic feature. Its constant movement results in a continuous welding process of consistently high quality. The outcome: Precise and reproducible welding results.

The process tape transmits the welding current and protects the contact surfaces of the electrodes from contamination. This significantly increases the service life of the electrodes, making up to 20,000 welds possible (depending on the application). Each welding spot is 100 percent reproducible, allowing users to benefit from the high process reliability. Since there is no direct contact between the electrode and the metal sheet, the welding spots are spatter-free, and the time-consuming re-milling of the electrodes is no longer necessary. Up to 7,000 spots can be welded without interruption with a single process tape.

Due to the high electrical resistance of the process tape, additional heat is conducted from the outside to the inside during the welding process. In aluminum applications, in particular, this means that up to 50 percent less energy is required – making the process very efficient. In addition to aluminum compounds, DeltaSpot can also be used to join titanium, magnesium, stainless steel, coated steel plates, and high-strength steels. Multi-plate joins are also possible without any problems. The user can simply swap the process tape in order to process a different material composition with the same spot welding gun. This makes DeltaSpot a versatile resistance spot welding system with clear process advantages in numerous applications

MODULAR DESIGN AND GOOD ACCESSIBILITY

Another way of executing spot welding processes cost-effectively, flexibly, and simply, is offered by Fronius with the new DeltaCon spot welding guns, which will also be available with a welding gun adjustment feature. This function helps to fine‑tune the gun before the actual welding process and prevents the sheets from deforming due to an inaccurate setup. The Basic and Basic plus versions are so-called “seventh-axis systems”, whereby the welding gun adjustment is carried out by the welding robot. With the Loaded model, this task is performed by the Fronius welding controller.

The DeltaCon guns feature a modular design and have the same main components in both the X and C geometries. This allows the user to flexibly tackle a wide range of welding tasks. Their narrow design also ensures good accessibility. There are no more parts protruding from the side of the gun, while all hoses and cables are now well protected inside the gun body. The transformer is already integrated in the base body, has its own cooling circuit, and is suitable for all aluminum applications. Thanks to their intelligent arrangement, the individual modules are easy to install and remove during installation and servicing, which keeps downtimes to a minimum and enables high levels of productivity. As a universal solution, users can connect the DeltaCon spot welding gun to all different types of robot.

The continuous process tape of DeltaSpot ensures that each welding spot is absolutely precise and reproducible.