chainflex® bend radius: know your limits
When using cables, no matter what the type, it is important that the minimum bend radius is considered and adhered to.
What is a bend radius? The bend radius is the radius at which a cable can be bent without damaging its integrity or function.
For cable carriers, also called e-chains® or energy chains, the minimum bend radius must be greater than that of the cable so that cable safety is maintained. Energy chain manufacturers offer different bend radiuses to allow customers to correctly match them to their cables. The bend radius of the e-chain® should be greater than the largest radius requirements of the cables inside – this can be obtained by multiplying (bending factor x overall diameter (OD)).
This compliance ensures long cable lifetime and, ultimately, application lifetime: too tight a bend radius and the cable elements will fatigue quickly. The larger the radius, less stress will be exerted on the cables – in turn producing a longer service life.
Moreover, operators must note the advised temperature range of the cable in order to not allow the cable to become hotter than is safe, since the materials might break down. Similarly, cold temperatures can make the cable materials stiff and brittle, reducing the life.
At igus®, all of our chainflex® cables are tested in the 3,800m² test laboratory, located at our headquarters in Germany, to ensure the figures that we release allow customers to find the safest, most long-lasting cables for their applications.
The tests on our chainflex® cables have been carried out for over 25 years and continue to do so over a wide variety of specific strokes and test regimes.
Thanks to this testing and expertise, the flexing lifetime of our cables can be guaranteed for 36 months; even in harsh and unusual environments.
The 7 commandments
The resilient designs of our cables can be summarised by the seven basic rules we proudly abide by:
- Strain-relieving centre: protect the braiding structure for reliable and safe cores.
- Optimised conductor design: optimal strand diameter, pitch length and direction for safe bending.
- Core insulation: non-adhering but supportive insulation materials.
- Core structure: braided or layered structure to ensure optimised short pitch length.
- Inner jacket: extruded inner jacket, rather than woven fabric or filler, ensures no fragmentation.
- Shielding: tightly braided structures ensure high EMC and torsion protection.
- Outer jacket: jackets made of PVC, PUR or TPE meet myriad specifications, such as UV resistance, low-temperature flexibility, oil resistance – and, ultimately, cost-effectiveness.