by Iulia Degeratu
Within the work package Process Development, Valk Welding has developed a novel water cooled torch, called the MIG II.
The trigger to start this development was the large heat build-up in the torch occurring during the WAAM-process. Too much heat in the torch has a negative effect on the process and its continuity. The new torch is made with two fully separated water cooling channels: one channel is used to cool down the inner tube of the torch, holding the contact tip like any other classic water cooled torch; the innovation lays in the other channel which is used to cool the outer tube, holding the gas cup. This outer tube is made of double wall pipe, allowing direct water cooling of the gas cup. Within the torch, the gas flows through its own channel, separated from the cooling channels.
For WAAM, the cooling of the torch is crucial to ensure a continuous process and increase productivity. The fully separated, water cooling channels prevent heat build-up during WAAM, which can even double the productivity of the process. The new MIG-II torch is compact and lightweight. Moreover, it has a longer contact tip than other designs, giving a better support to the wire running through the torch.
Furthermore, Valk Welding has developed a new model for their servo-pull wire-feeder-unit, called the Servo Pull III. The new model has an innovative design and a water cooling system for the servo-motor, controlling the wire feed.
These innovations (the MIG II torch and the Servo Pull III wire feeder unit) delivered by Valk Welding contribute essentially to one of the goals of the Grade2XL project, of doubling the productivity of the WAAM process.