Practising what we preach: Quality Czech

ABB Elektro-Praga employs robots to save on wages, boost production and raise quality levels.

When the ABB Group acquired Czech electrotechnical engineering manufacturer Elektro-Praga in 1993, it was lured by two major selling points: high-quality products and low wages. That’s not surprising; Czechs have a long tradition of high-quality light engineering that was strong enough to survive 40 years of communism. But with the country’s accession to the European Union salary levels have been steadily climbing.

In 2009 Elektro-Praga (now re-named ABB Elektro-Praga) decided to install a new production line at its factory in the northern town of Jablonec nad Nisou, as the company could no longer rely on cheap human labor. Instead, it chose a production system that featured three IRB 140 robots from its sister company, ABB Robotics. “Although it’s small, the robot is exceptionally fast, accurate and powerful,” says Petr Prade, Chief of Design at system integrator MMT, the firm that built the new production line. “It has one of the fastest cycle times of any articulated robot.”

IRB 140 industrial robots with their tiny footprint “If you save space, you save money,”

ABB Elektro-Praga specializes in wiring accessories (low-voltage circuit breakers, switches and sockets, movable components and control products) and employs the robotics installation for the company’s assembly line of dual plug sockets. But the company also plans to use the same production unit for at least four other product lines.

“That’ll present no problem at all,” says ABB Robotics'' Senior Account Manager Vladimír Slabý. “It takes no more than 10 minutes to adjust the production line for another product variant. It’s possible to change the variant up to 30 times per week, resulting in real ‘production to order.''"
"For multiple operations, six-axis robots are always the best way to go. We favor the IRB 140, as it is easy to re-use in any future installation."

The production unit that MMT designed incorporates three vision systems − the ideal solution, Prade believes, for handling applications such as high-speed assembly or semiconductor inspection.

The IRB 140 robots have their own sophisticated control systems that allow arbitrary task programming. Any number of visual inspection can be included within the cycle by simply amending the robot and PLC programs. “If there’s a blockage or something like that, the computer screen will tell me precisely where and what the problem is, so the time that the system stands idle while I fix it is absolutely minimal,” says operator Jana Dolková, who used to help assemble the sockets by hand before the robots were installed. “And of course,” interjects quality control inspector Petr Neuman, “unlike humans, the robots leave no fingerprints!”

The IRB 140’s flexibility has proved invaluable elsewhere in the production plant. “Some months ago, we experienced problems with the material feed on another assembly line for light switches,” recalls Technology Department Manager Vladimír Růžička. “We solved this by using another IRB 140 linked to a vision system.” Now, Růžička says, the small metallic frames are being fed reliably. “And the line’s output has been boosted by 15 percent − just by using a single robot!”

“For multiple operations, six-axis robots are always the best way to go,” says Prade. “We favor the IRB 140, as it is easy to re-use in any future installation.” But according to Slabý, the clincher is the compactness of the robot, which allows it to fit into a very small space, or even another machine. “If you can save space, you save money,” he says. “And after all, saving − and making − money is what this robot is all about!”