Page 933 - ASEAN Chainflex Catalogue 2023

chainflex … ... lasts or your money back!
®
The tricks and ingenious features of...
The production of the shield itself is very time-consuming
and cost-intensive and may have been the reason for the
use of open braid shields or even simple wire wrappings.
The disadvantages are obvious: open shields only possess
a limited shielding effect when moving - motion reduces this
effect even further. The type of shield is therefore an important
point that is not even mentioned in some catalogues.
In its approx. 70% linear and approx. 90% optical coverage
cables, igus eliminates these weaknesses by means of an
®
optimised internal structure. In virtually all shielded chainflex
®
cables, a gusset-filling extruded inner jacket over the core
structure is used. This "second jacket" fulfils two tasks:
It holds the core structure together and guides the
individual cores as in a channel.
It serves as a firm, round base for a very tight-fitting
shield. see picture 1.
Shield wire breakage - and how this can
be prevented
Even during the production of the shield, there are many things
that can be done correctly - or incorrectly. Here, an important
parameter is the braiding angle.
In the case of "chain-suitable" cables, tensile load on the
shield wires in the outer radius of the cable must be taken
into account. If an unfavourable braiding angle is used, the
tensile load increases even further and shield wire breakage
is the result. The consequences range from reduced shielding
effects right up to short circuits whenever the sharp wire ends
penetrate through the fleeces or foils into the cores. Here is
a useful tip: If, after the insulation has been stripped off, the
shield can be easily pushed back over the jacket, the shield
is then usually unsuitable for use in moving energy supply
systems! This is a problem that igus has now solved with its
®
novel approach:
The shield braiding angle determined in long-term tests
efficiently neutralises the tensile strengths and is therefore
Jac ket b reak age of highly suitable for energy chains.
(36x0.14mm ) after only Due to the stable inner jacket, the shield cannot become
2
900,000 double strokes with uncontrolled.
a bend radius factor of 7.8 x d
The shield itself has a torsion protection effect on the
wound structure.
Jacket abrasion/jacket breakage
Whilst defects in the internal structure are hardly detectable
on the outside, jacket problems are immediately obvious.
The jacket is the first protection for the complicated internal
structure. This is why broken, worn and swollen jackets are
a serious quality defect. To prevent this problem, the igus
®
customer can select from 7 jacket materials to adapt their
energy chain cables to suit the conditions of the respective
Picture 1: Optimised shield braiding angle over environment.
gusset-filling extruded inner jacket
926
...the chainflex design and why we feel so confident about this design
®
Gusset-filling extruded jacket the cores during the winding process, are completely filled
with jacket material by the high extrusion pressure. As a result,
Here, not only is the material an important factor but also the jacket material creates a channel-like guide which ensures
the production process. In the case of the so-called "chain- the cores have a defined longitudinal movement. The jacket
suitable" cables, the jackets are usually produced extruded to also provides a supporting function for the structure. see
the form of a tube and therefore do not provide the structure picture 2.
with the necessary support for constant bending. The wound
structure can fall apart. The quality bundles of igus chainflex
®
®
cables
Therefore, igus is the first manufacturer of energy chain
®
systems to offer the so-called the "gusset-filling extruded" Strain-relieving centre
jacket. Cores in bundles
Gusset-filling extruded inner
Here, the jacket material is injected between the core structure jacket in shielded cables
powdered with talc and ensures that the core structure does Enclosed shield braid
not open up and also makes sure that the cores are guided Optimised shield braiding angle
as in a channel. The special characteristic of this type of Gusset-filling extruded jacket
production is that the intermediate spaces created between
Picture 2:
Gusset-filling extruded
jacket
7 basic rules for a good cable
1. Strain-relieving centre
Clear space is created in the centre of a cable according to 4. Structure
the number of cores and the cross section of each cable. This The structure must be wound around a stable, tension-proof
centre should be filled, as far as possible, with a genuine centre centre with an optimised short pitch length. However, due
cord (and not, as frequently the case, with fillers or dummy to the insulating materials being used, this wound structure
cores consisting of waste materials). These measures will then should still used. Starting from a quantity of 12 cores, a
efficiently protect the structure and prevent it from wandering bundled design should be used.
into the middle of the cable.
5. Inner jacket
2. Stranded core
A gusset-filling extruded inner jacket must be used instead of
With respect to the selection of core strand wires, the maximum inexpensive fleeces, fillers or accessory fillers. This measure
flexibility has proved to be the best solution. Although very ensures that the core structure is efficiently guided in
flexible conductors can be made using very thin individual longitudinal direction. Moreover, the wound structure cannot
wires, these conductors can allow formation of kinks. Long- fall apart or wander off.
term testing provided the result of a combination of strand wire
diameter, pitch length and pitch direction as the best overall 6. Shielding
bending-resistant solution. The overall shield should be made tight using an optimised
shield braiding angle over an extruded inner jacket. Loose
3. Core insulation open braids or wrapped stranding reduce the EMC protection
The insulation materials must be made so that they do not stick considerably and can fail very quickly due to shield wire
to one another within the cable. Furthermore, the insulation breakage. A tight total braid shield also has a torsion protection
is also required to support the stranded individual wires of effect on the wound structure.
the conductor. Accordingly, only the highest-quality, high-
pressure-extruded PVC or TPE materials that have proved 7. Outer jacket
their tested reliability in millions of core kilometres are then
used in energy chain applications. The material-optimised outer jacket can fulfil many different
requirements: from UV-resistant to low-temperature-flexible,
and from oil-resistant to cost-optimised. But these outer
jackets must have one thing in common: A jacket material
must be highly abrasion-resistant but not be allowed to stick
to anything. It must be flexible but also provide a supporting
function. In any case, the jacket should also be extruded under
pressure (gusset-filling).
927
927