Switching to 2 welding robots in 3 shifts

General sub-contractor C-MEC, employing 100 people in Belgium and another 100 in the Czech Republic, specialises in sheet metal processing, machining, coating and assembly. The products are mostly fine-mechanical components with small dimensions for electronic equipment and sub-assemblies for media, digital cinema, defense, aviation and the medical sector. Following the takeover of the two sub-contractors the range was considerably broadened and the dimensions increased substantially. The processes at C-MEC are largely automated. "What we can't automate we leave to our Czech location", explains production supervisor Krist Bleuzé. C-MEC therefore has the latest, fully automated lasers, punch/laser combina-tions, press-brakes, turning and milling centers, powder coating lines, and so on. "Until recently we were only doing the welding manually. But the shortage of professional welders soon left us facing capacity problems."

Step to welding robotisation

There were a number of products that lent themselves better to robot welding. This was a good match for the company's approach to automation and was intended to save a great deal of time. The idea was to have 2 welding robots up and running within a year. For this purpose C-MEC sent a number of products to 3 robot integrators and invited them to demonstrate their systems. Krist Bleuzé: "Valk Welding is a known name in the welding industry. The company has a lot of knowledge and experience in welding robotisation, supplies a complete system and offers an outstanding support service. Their demo and both the welding robot and offline programming system, turned out to be the most convincing."

Learning and development process

Tom Vandewoestijne: "We took the first step last year, even though we realised that welding with a robot is a 3D process and therefore much more complicated than 2D laser cutting and punching, and we did not yet have any experience with robot welding. Our ultimate goal was to introduce the use of 2 welding robots in 3 shifts in stages. That plan turned out to be overambitious. We seriously underestimated the impact of the new technology. We didn't put enough time into this. We've now been using the first welding robot for a year, and are reliably welding repeat orders for several customers without any dif-ficulties. We regard that as a learning and development process. For the time being we're restricting ourselves to steel and are currently redesigning other prod-ucts to make them suitable for the welding robot. We won't be ready for another welding robot until we've gained enough experience."

30% Production gain

Krist Bleuzé: "Despite the new growth forecasts, the results up to now are meeting all expecta-tions. As well as a 30% production gain we are also achieving higher and more consistent quality. We can't use the welding robot for all of our products just like that. In some cases the series are too small, or the pieces are unsuitable. But we're still doing our utmost and trying everything we can. This is always done in consultation with the customer, because sometimes the piece has to be adjusted. One thing that isn't in any doubt is the weld quality: it's perfect.

Optimisation

The work on the welding robot is evaluated every day at C-MEC in order to find ways of improv-ing the process. Krist Bleuzé: "It turned out in practice that we needed half the time for weld tracking. Supplying pieces more accurately saves time on tracking. We've also learned that welding jigs can be made more smartly, in such a way that products can be loaded and unloaded more quickly." We're focusing not so much on the welding process itself but more on its prepara-tion.

Scale size

Hundreds of orders go through the company's production process, most of which is unmanned. Tom Vandewoestijne: "With this number of orders we are able to use our production capac-ity profitably and produce more effectively and quickly than a brand supplier or manufacturer. Manufacturers therefore focus more and more on marketing and development, and outsource the production. Since we do all of the processes in-house, our delivery times are highly competi-tive. Welding robotisation has helped us to re-duce the turnaround times even more. That has enabled us to attract new orders that we couldn't have taken on without the welding robot."
www.c-mec.be