WIRE ROPE
“They are also easier to install than
steel wire rope, while providing the
same load-bearing capability as steel
wire ropes that weigh seven times as
much. Additionally, they are extremely
resistant to environmental damage,” the
manufacturer adds.
Other areas that rope manufacturers
need to take into account are abrasion
resistance and crush resistance. To
overcome these issues UK rope
manufacturer Bridon has introduced
the Dyform eight strand ropes and
multi-strand wire ropes.
“Dyform is a technology that helps
shape the outer strands of a rope so it
produces a smoother, lower contact force,”
Jon Templman, Bridon CEO, explains.
“This reduces the amount of abrasion and
wear during spooling.”
“Dyform eight max ropes are very
popular for mobile boom hoist cranes,
for example,” Chris Newton, Bridon
technology director, adds, “However, for
high-speed, long-lift cranes the key is
good crush resistance and multiple layer
spooling. The stability of that is
really important.”
Performance challenge
The shift in the industry for high-speed,
long lift cranes is challenging rope
manufacturers worldwide, as Markus
Klinck, industrial engineer and product
manager at rope manufacturer Casar,
explains, “Cranes in the construction
industry have increasing capacities and
are getting bigger and bigger. These
huge cranes have big lifting heights
and are spooling very fast; therefore, it
is important to have ropes with close
diameter tolerances and very good
spooling behaviour.
“In addition, another effect of the
increasing capacities is that the requested
minimum breaking loads for the ropes are
getting higher and higher, while the crane
components are designed to be as small
as possible. This challenges the wire rope
manufacturers worldwide,” Klink adds.
To meet such demands Casar developed
the Casar Starlift Pro. “The new Casar
Starlift Pro is a rotation resistant wire rope
made of only compacted strands except
the king strand,” Klinck explains. “Based
on the high filling factor, the breaking
force is very high. The production
tolerance is between +2 and +3.5 % and so
significantly tighter than the usual market
tolerance of +0 to +5 %.”
Due to its high resistance to twisting
under load, Casar Starlift Pro can be
used in hoist applications such as tower
cranes, mobile cranes or crawler cranes.
For high bending fatigue performance,
Casar offers the Casar Superplast10 and
the Superplast10 Mix designs, which are
flexible wire ropes with high breaking
force. The ropes have 10 outer strands, a
plastic coated IWRC and a double
parallel design.
It is not only wire ropes that are being
developed for high-speed, long-lift
cranes. “It is probably true to say that
synthetic rope offers the best option for
high-speed, long-lift cranes,” says Jorn
Boesten, segment manager offshore at
DSM Dyneema. “Synthetic rope can easily
be made torque neutral. Most of our
customers’ ropes are made in a 12 strand
construction, which is inherently torque
neutral, so it is very suitable for long lines.”
Development and testing
Once a rope has been designed and
produced it undergoes rigorous testing.
This is usually carried out in specially
built testing facilities. Verope, for example,
sends rope prototypes to the R&D facility
in Contwig, Germany, to be tested and
evaluated. At the centre tests carried out
on the ropes include flexibility, breaking
strength and rotational stability. To test
and measure the lateral pressure stability
of rope while under load is another
method used by Verope.
“Rotational stability is calibrated on a
specially designed test stand to determine
the angle of rotation and torque. These
results allow Verope to calculate the torque
at maximum lifting height to optimise
the rope design to work in greater lifting
heights,” a spokesperson from Verope
explains. The tests on Verope’s rotation-
resistant ropes are carried out at the
University of Clausthal in Germany. The
ropes are intended for use in multi-layer
drum spooling.
Casar, which has been part of the
WireCo WorldGroup since 2007, has
testing facilities at its plants around
the world. “Beside the standard testing
machines to measure breaking strength,
rotational behavior, bending fatigue and
elongation, we additionally have special
Casar’s Starlift Pro wire rope is
rotation resistant
Global technology leader
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Our superiority relies on continuous innovation,
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