This article describes robotic FCAW welding with using a tandem torch for welding bearing parts of mobile truck crane. Follow primary objective advantages of tandem welding compared to welding with a classical single wire. Mainly in light of welding speed, welding productivity with reference to resulting weld quality. In the article is firstly described the comparison of both robotic welding cells and also technologies of production, including technological welding processes for single wire and already mentioned tandem wire robotic welding cell. The secondary is described modernized robotic welding cell used benefits from tandem torch with laser off-line sensor servant to searching weld position. Part of the tandem robotic welding cell is as well as two axis welding positioner. In light of used welding technology, we speak about shielded arc welding process with metal flux cored wire.