igus® e-tubes drive bending tool of top manufacturer
TRUMPF Inc. is a global leader in manufacturing machine tools. In one of its most complex and popular bending machine product lines, energy tubes from igus® are used to guide and protect cables.
The company's North American subsidiary is located in Connecticut. There are a total of 70 subsidiaries, and nearly 11,000 employees help generate annual sales of more than $3 billion. The Connecticut facility is the largest subsidiary within the TRUMPF Group and is the largest manufacturer of fabricating machinery in the United States. 
More than 600 units of the TruBend 5000 series bending machines are manufactured each year. It achieves press forces of 50 to 320 tons and edge lengths of 1.25 to 4 meters.
Saving assembly time and costs
TruBend Series 5000 units have a bending tool for large or heavy parts upon which the sheets are processed and placed. The tool supports up to 30-degree angles and its height can be automatically adjusted.
“For large and very heavy workpieces, this support is necessary to bend the sheets accurately, requiring only one operator,’’ said Volkmar Schmidt, Head of Technical Purchasing at TRUMPF Maschinen Austria. The bending device can be moved freely from left to right.
TRUMPF relies on energy chains from igus® when the bending device is moved. igus® is a global leader in manufacturing cable carriers, flexible cables, bearings, linear technology and other engineered plastics.
For the Series 5000, TRUMPF sources the chains as enclosed tubes the igus® R4.1L series, using overlapping lids instead of the standard crossbars. Similar to the open E4.1L version, the lids can be opened at both ends and pivoted upwards by 115 degrees, which saves assembly time and costs. If necessary, they can be removed completely, fitted again, and closed by pressing downward.
Tubes Protect Interior Cables
TRUMPF prefers the closed version to give the Series 5000 machines a more discreet appearance. “We feel that it is visually more attractive if only one black tube can be seen instead of colored cables or colored dots on the outside of the machine,’’ Schmidt said.
Other important factors of the energy chains are the easy assembly, small bend radii and the maximum filling volume and minimum exterior height. The E4.1L has considerably less mass than the E4.1 heavy-duty chain, and the e-tubes are about 30 percent lighter.
The patented interlocking undercut design of the chain link and the double stop-dogs with large surfaces were incorporated from the E4.1 design. The design features in the E4.1L provide strength and also allow larger unsupported lengths. The rolling noise is also minimized, resulting in quiet operation of the chain.
Secure layout of cables
The mechanical load in the bending device is minimal, since the movement is manual and not very dynamic. “More important for us is the interior separation of the chain so that all cables can be laid securely in separate chambers,’’ Schmidt said. “To achieve this, igus® offered advice and guidance on site. For smaller tasks we do the design of the chain online. But for more complex designs or prototypes, personal support is important to us, so that we can be sure we’re on the right track.”
TRUMPF keeps very few igus® energy chains in stock. The company usually orders 1-2 days before production, and the e-chains® are then supplied in the correct length directly from igus®. The igus® service is critical to TRUMPF’s success. “I’ve worked for TRUMPF for 25 years, and cannot remember a time we did not use igus chains,’’ Schmidt said.
See how the TruBend Series 5000 works on this video. Viewers can see the bending device at work at the 2:07 mark of the video.
