If you can automate the loading of products onto machining equipment, that must also be possible for the welding production.
Valk Welding realized one piece flow production at Marel Stork
That was the underlying idea when Valk Welding, working in partnership with Marel Stork Poultry Processing, developed a production cell in which the handling and logistics surrounding the welding robot are automated. The result is a welding production cell that produces completely continuously, is entirely designed for one piece flow production and yields a substantial saving in manpower.
Marel Stork Poultry Processing had the drive to always be the first to adopt new production technology. The company became involved in welding robotisation at an early stage, and in 1996 was one of the first users of Panasonic’s offline programming system DTPS. This was also Valk Welding’s first customer for a welding robot with the Arc-Eye laser sensor.
Full confidence in the supplier
Industrial Engineer André Kouwenberg: “When it comes to welding Valk Welding and Panasonic incorporate a lot of our feedback in later versions. That open approach and the short lines of communication have resulted in our gaining a lot of confidence in Valk Welding’s people over the past 25 years, which is why we were willing to take on the development of the new production cell. There are probably other system integrators that are able to do this, but Valk Welding is increasingly raising its profile in this market with its specific knowledge of welding matters.”
One piece flow
André Kouwenberg: “Now we produce as little as possible in batches, but will instead place the entire process from laser cutting, welding and milling in a single flow. If for example we need 20 components, we won’t wait until all 20 are ready but will send each completed product straight to the milling department. That actually amounts to working according to the Quick Response Manufacturing principle, which we have ‘borrowed’ from car manufacturers. Each part has to be processed directly without creating any dead time and the delivery times are kept as short as possible.”
Handling robot operates welding robot with 2 workstations
In the new production cell parts are clamped onto pallet carriers and stored in one of the 58 pallet positions in the warehouse. When a part is to be welded a handling robot (Panasonic HS-165) collects the pallet in question from the warehouse and mounts it on one of the two workstations of the Panasonic welding robot. While the welding robot is welding the component, the next pallet is changed on the other workstation. As soon as a pallet has been welded with one or more components, the handling robot places it back in the warehouse. “The cell contains 58 jig carriers with a total of 240 different jigs. By creating the right combinations between fast and slow movers you achieve the right production balance to maintain a continuous workflow, explains André Kouwenberg.
Software determines production
The software determines which part is to be welded first. The software advises the operator rather than the other way around. The operator can however interrupt the system if the workflow for a simple part has to be stopped. For that purpose there is a third workstation at the front of the cell where the operator can insert and take out a component himself. Without that option the system would be too rigid and you would run the risk of the assembly having to wait needlessly for a single part. The software was written entirely by Valk Welding’s software engineers.
André Kouwenberg: “With the latest robot technology and logistics automation we will be able to move forward efficiently and flexibly for another 10 years.”