In the Tandem Weld process, two arcs burn in a common molten pool. Tandem Weld is characterised by two electrically separated processes which match each other perfectly. This possibility opens up a multitude of combinations. The front wire ensures a safe penetration, the back wire quickly fills big joints with filler material. The high deposition rate results in weld speed and in volume filling. Therefore, Tandem Weld is suitable for thin and for thick plates.