CEJN is a leading Sweden manufacturer of quick connect couplings, which are used to connect air, gas and hydraulic lines from automotive manufacturing to firefighting equipment, and from wind turbines to agriculture. CEJN has used industrial robots to assemble and move its products for several years, however one task – the location and assembly of fine screw threads between parts – has always been difficult to automate and ergonomically unfriendly for people.
“As almost all our products are structured in the same way, therefore this assembly task is important to us. The problem is that it is extremely non-ergonomic for human wrists. That’s why we have been looking for a robot that can manage this specific task,” says Filip Palmkvist, Operation and Maintenance Manager at CEJN.
Palmkvist first saw ABB’s YuMi dual-arm collaborative robot at a trade fair in Jönköping, Sweden, where it was working with people - and without safety fences - to assembly lamps. It was here that Palmkvist first had the idea of exploring the possibility of a collaborative application to automate what could not be automated before.
Proving the concept
CEJN’s collaborative journey began with a pilot study, done with ABB’s Collaborative Robot Test Center and Robotdalen, a system integrator in Västerås Sweden. “There we tested whether the robot could do what we wanted it to. They took our products and created a complete and finished application. It was a very good opportunity that enabled us to see how the robot would work in our operations; we felt reassured about the concept, and it was easier for us to then make the investment,” Palmkvist says.
3D printing was essential to the pilot study and allowed the precise testing and fine-tuning of different robot grippers for the application. “The fingers produced during the tests are the ones used in production today,” adds Palmkvist. The solution also includes an integrated vision system which is used both to locate parts and to ensure that they are assemble to the right quality.
Automating competitiveness and flexibility
Although CEJN’s original goal was to automate the screw assembly process and give workers more ergonomic tasks, the YuMi robot is also helping to keep manufacturing economically viable in a higher wage country.
“The whole manufacturing industry in Europe, including the couplings sector, must constantly strive to boost its efficiency and competitiveness and avoid costly strain injuries among staff. CEJN also has assembly operations elsewhere, such as in China, but we see it as a strength to be able to have our production in the same location and same building as our development. The collaborative robot has been a important key to creating competitiveness. It enables us to cut manufacturing costs, which is essential to enable us to have manufacturing operations in Sweden,” says Gunnar Hellichius, CEJN Production Manager.
"It enables us to cut manufacturing costs, which is essential to enable us to have manufacturing operations in Sweden"
With the help of YuMi, CEJN has also succeeded in increasing its flexibility: “We now work with flexible work stations. When we run a low-volume production operation, a fitter can stand and staff the work station, and when the volume grows, we can place a collaborative robot in parallel with the fitter. We thereby create flexibility between high and low volumes and cut our costs for the moderately high to higher volumes,” said Hellichius.
And what do the staff think of their new robot co-worker?
“We started by building a work station on wheels to take the robot around to the fitters, enabling all of them to examine it and see what kind of technology it was and what the robot can contribute. We wanted to show that this is not a threat, but instead a reliable workmate who will help make them more productive while at the same time taking on the less attractive tasks. It was very well received, and today the fitters come and ask whether they will also soon get help from their robot colleague,” Hellichius added.