This welding equipment relies on an automatic MIG procedure of the two lateral pins working on intermediate hinges with large cylinders. External joining of the pin takes place by means of circumference welding with a torch fitted on a special spindle. The spindle is equipped with a pneumatic centre and passage for the torch’s wiring. The inner joining of both pins is carried out with a second torch by interpolation of two Cartesian axes, which enable clearing of the welding area.