Engineers and industrial planners agree that energy efficiency is critical for industrial progress. Among welding operators, energy efficiency goes well beyond the electrical characteristics of the process: it has come to include the manufacturing process as a whole. This is particularly relevant to upstream and downstream work processes.

To be as energy-efficient as possible, welding processes must reduce spatter, achieve high weld speed, and significantly improve gap “bridgeability,” while offering controllable heat input. Fronius provides three intelligent and practical solutions — cold metal transfer (CMT), LaserHybrid, and DeltaSpot, the spot welding process — that improve efficiency and offer a quick return on investment.

Robotic welding may be cost-effective robotic, but it must be a continuous, uninterrupted operation. Robots equipped with conventional metal active gas (MAG) welding systems must stop frequently in order to clean welding spatter from the nozzles. This offers plenty of scope for savings in time, energy and material, as Hyundai Motor Co. has demonstrated. Hyundai's switch to the CMT process resulted not only in far less welding spatter, but in a considerably more stable metal transfer and a significant reduction in the tilt angle of the electrode. This alone reduces the stoppage time of the robot welding cells by more than 60%, and increases the efficiency of the electrical energy used.

If gap bridgeability is as high as possible, the time and costs required in preceding production stages is reduced and there is no need to fix the parts to be welded in position. Heiko Steinmetz, who oversees production planning technology and concepts, forming, joining and assembly technology at Mercedes Benz, sees advantages in using LaserHybrid welding in batch production. Compared with conventional MIG or laser processes that use a cold wire feed, LaserHybrid achieves three times the welding speed and, thanks to the lower energy input, consumes far less electrical energy while simultaneously reducing thermal distortion.

Conventional spot welding, especially of aluminum components, is characterized by high electrical consumption and high levels of electrode wear. The result is frequent stops while the electrodes are changed and high electrode costs.

The DeltaSpot spot-welding system features a continuous process tape that runs between the electrodes and the sheets. This protects the electrodes, brings clean, fresh material to the contact points before each weld, and reduces total energy consumption. The flexible and totally controllable process permits continuous spot welding of a consistently high quality — regardless of whether the material to be welded is aluminum, different grades of steel, and galvanized, or organically coated sheets. The demonstrable increase in product quality and system productivity, the reduced waste, and energy and material consumption savings all come together to provide a more efficient and stable production process.