Highly flexible cables raise machine
availability in the furniture industry.
Robust in rough environment
In the ADA furniture factory, there are many things that move: disk sawing machines, bearings, material cutting machines and many more. The motor and control cables used here have to be pretty much resistant and flexible in a fourteen-hour work a day. Requirements that are ideally fulfilled by the flexible igus® "chainflex®" cable range specially made for energy chains.
A leather cutting station of American origin had the ADA's technical department pretty much in sweat for several years. "There were problems with the machine right from the start. I've never seen in my whole life such cables, how they were integrated there. We had to replace the cables every two months," reminisces Johann Doler, technical director, about the station with a shudder, which had brought him much worry and work. A cable replacement meant a time wastage of up to one day: "Detect the failure, pull out the cable, put them back in - which moreover was not so simple at all, because the cable must pass through not only the energy chain but in some duct or the other of the machine," says the ADA technician.
Prevent expensive cable breaks
Doler intensively looked about for reliable cables. The saving call came from the energy supply system specialists igus®. Even though the bending radius of the energy chain in this machine was very small and there remained little space for the cables, Gerald Weber at the igus® of sales department predicted an enormous increase in service life, if ADA changed to a "chainflex®" cable CF9 for narrow bending radii. And he was right. The igus® cable specially developed for the highly dynamic application in energy chains survives the longest. Johann Doler's persistent problem, the leather cutting station, is indeed long past, but the collaboration with igus® certainly is not. Quite the contrary: As soon as the original cables in the machines and facilities of the furniture manufacturer do not meet the service engineers' expectations, one now relies on CF5/CF6 cables and/or a cable type from the "chainflex®" range for energy chains, based on the positive experience with the chainflex® cables.
Overall the cables are pretty much pushed to their limits at ADA. Initial symptoms of fatigue became noticeable in momentary wire pauses. "Often a failure occurred only sporadically at the beginning, which means it cannot be perceived at all in a short while. If for example a measuring system in an inaccurate machine is not about thousandth of a millimeter, but about large tolerances of three to four millimeters, brief misfires are possibly not noticed at all. In our disk saws, for example, slight variations would be rarely noticeable, as most of the cut disks are anyway reworked", clarifies Johann Doler. Things are completely different in cloth cutting machines. As the sudden discontinuation of impulses and the thereby associated short-term fast operation of the machines absolutely leads to a gross amount of waste.
The worst cable break that the Technical Department Manager at ADA-Möbelfabrik GmbH can remember caused damage of around 10,000 Euro. “An automatic plate bearing started moving and got increasingly faster due to the cable break, because no more feedback came and in the end even knocked the buffer off,” outlines Doler.
With chainflex® cables, the ADA man feels somewhat free from such technical afflictions: they do cost a bit more to buy, but have a much higher service life. “I would rather pay a bit more money if it gets me a longer operating time. Because the less often I have to replace a cable, the better it is for our engineers and for a safe working operation. “Of course we have tried out different makes but then noticed in direct comparisons that the chainflex® cables last longest,” says Doler summing up.
Cable breaks happen easily. Usually without any warning. Although there is the so-called “corkscrew”, which appears with many makes as an obvious pointer to an impending wire break, usually you are left in the dark even with a visual inspection as regards the actual state of the cores and wires. They are usually hidden away in e-chains®.
Stable braiding in bundles
To raise the reliability of its cables, igus® banks on a very complex, multi-stranded interior. In this way – so-called braiding in bundles – all the cores change the inner and outer radii of the bent cable several times at the same distance. Thereby the stranding remains stable even in extreme bending stress. "Besides its reliability, I like the "chainflex®" cables moreover because they have a compact built. That is a great advantage for use in energy chains, because I got more space in the chain," clarifies Johann Doler. Incidentally, he is in the meantime also convinced by the igus energy chains. These are indeed used in the ADA furniture factory only when the existing chain supplied with the machine goes to pieces: "If the whole energy chain has to be replaced, we take igus®. If only half a meter is damaged and the entire chain is ten meters long, a meter of the original chain is mounted. " Accordingly the ADA technician keeps in storage a couple of meters for backup of all popular chain types. In the cables, on the other hand, a couple of 4 x 1.5 as well as 4 x 2.5 motor cables as well as twelve- and seven-pin control cables CF5/6 with several cross sections of 0.5 to 1 square are ready as a precaution for any troubleshooting in the machines.
On average a cable was replaced every two to three months somewhere or the other in the ADA furniture factory in Baierdorf. Sometimes only on the off-chance, as Johann Doler admits: "The bad thing about such cable failures is that they cannot be measured with any normal ohmmeter. If ultimately no failures are found, the cable is sometimes just replaced. " If the appropriate cable is not in stock, the technician resorts to, as far as allowed by the space in the energy chain, a strong cross section. If this doesn't function either, the East Styrians trust the prompt delivery service of igus®. The required features like bending radii, cross section, application area, shielded or non-shielded, etc., are clarified by telephone and the package is promptly on its way from the store in Cologne to its destination within 24 to 48 hours.
