CMT: Premium class serial production

VW Sachsen (Germany) is the first automobile manufacturer to use the CMT process in car body manufacturing for the Bentley Continental and the VW Phaëton...

VW Sachsen (Germany) is the first automobile manufacturer to use the CMT process in car body manufacturing for the Bentley Continental and the VW Phaëton. CMT welding the C-pillar from three parts of different thicknesses returns convincing results with 20 to 30 percent less heat input and spatter-free welding. This reduces clamping and logistic requirements and removes the need for finishing.

The 530 kilogram chassis for the Phaëton VW 611 and the Bentley 614 are produced at VW Sachsen's Mosel works. There is a fairly low level of mechanisation when joining load-bearing construction parts, and this tends to bind personnel and logistics resources.

The C-pillar is an important part of the construction, and comprises three parts with different thicknesses, 1.0 mm, 0.8 mm and 1.7 mm, which need to be joined. The quality of these joints is critical for two reasons. Both the stability and the appearance have to be perfect.

This is where the CMT welding process can be applied to best advantage. The 20 % to 30 % lower heat input, with these relatively thin metal work pieces, leads to a 50% reduction in metal incursion. This significantly reduces the need for time-consuming lifting and finishing of the C-pillar.

The second advantage lies in the fact that the CMT process is spatter free. Minimizing the finishing time required to remove spatter from luxury class bodies is an important aspect. Finally, CMT means more accuracy and welding speed.