How to use high-strength fibre ropes
Dyneema vs Aramid
High-strength fibre rope technologies has made advances in recent years. Yet fibre ropes are still rarely found outside the sports industry, although they have one clear advantage over wire ropes.
High-strength fibre ropes have made a name for themselves in recent years in comparison to classic wire ropes. And yet you still rarely meet them in public outside the sports industry. But they have a clear advantage: high-tensile fibre ropes can transmit at least the same breaking force as wire ropes with the same diameter.
Especially when space is at a premium, fiber ropes are a good option. They can be bent much sharper and with less noise over small sheaves for long service lives and all this with a very low dead weight. The low noise is highly appreciated in stage technology, then the rigging system does not ‘whir’ during the performance.
Only in two areas does a fibre rope cost a little more effort than we are used to from wire ropes: in the area of end connections there is still innovation potential to be able to connect a fibre rope economically to a rigid structure at 90 % or 100 % of the breaking force.
Moreover, it is not quite as easy to determine the current state of wear of a fiber rope. While in the case of wire ropes - in addition to measuring the diameter - broken, visible outer wires can be counted and plastic deformations can be detected, in the case of fibre ropes the interaction of use, fibre wear and environmental effects must be assessed.
With each new application, however, the experience knowledge and possibility of predicting the behavior of fiber ropes in use grows here. Compared to five years ago, we now know much more and are seeing more and more ropes made primarily of Dyneema and aramid in industrial use. Fiber ropes are not yet cheaper, but some savings can be realized through longer life cycles and smaller designs.
What actually distinguishes the two fibre types Dyneema and Aramid? In addition to the chemical compositions and manufacturing processes, two characteristic differences are particularly important for the user: UV resistance and the limit temperature. It is precisely in these two areas that the market leaders differ considerably.
While Dyneema is virtually insensitive to UV radiation, aramid reacts to UV radiation with aging and loss of strength of the fibers. On the other hand, Dyneema fiber is not as temperature-resistant as aramid. With Dyneema ropes, the interaction between the fibre and the coating can be affected from as low as approx. 60 °C. Aramid fibres, on the other hand, can withstand temperatures of up to 450 °C.
Dyneema ropes therefore dominate outdoor use, e.g. in sailing, kite surfing or in the operation of stadium cameras. Aramids are increasingly used, for example, in high-speed hoisting ropes and technical applications with high ambient temperatures.
Fiber ropes are being used more and more due to growing application experience and corresponding confidence. Wire rope will not disappear, but will certainly be gradually displaced from some applications.
If you are looking for a suitable high-tensile fibre rope for your application, simply contact us without obligation. Our experts in rope and lifting technology will be pleased to advise you on your project.
Konstantin Kühner, author of this article, is head of technology and development at Jakob Germany and a renowned expert for ropes and hoisting technology.