Ropeblock sheaves promote wire rope longevity and prevent block rotation or cabling, leading to lower costs and higher crane uptime. They have proven themselves over twenty years of use in a wide range of applications. Ropeblock sheaves experience notably less wear than other materials due to their use of graphite, which reduces friction between the rope and sheave groove. They also perform well in low temperatures down to -40°C. Ropeblock B.V. is an engineering and manufacturing specialist that produces sheaves and other lifting components used globally in critical applications.

1. ADVANTAGES AND AVAILABILITY
The Ropeblock sheave promotes wire rope longevity and helps prevent block rotation or
cabling, adding to a lower total cost of ownership and a higher crane uptime. Ropeblock
sheaves are accepted by all major class societies.
The design has proven itself in over twenty years of use and has led to being available in
hundreds of different bearing and D/d sizes, ranging from wire rope 10 mm to 76 mm or
bigger and a very cost effective solution.
WEAR
The notably better wear resistance in Ropeblock sheaves in comparison to other
materials is primarily explained by the graphite as established before in third
party testing. Once the rope and groove are a pair (are run in), the wear almost stops
because of its inherit graphite, and shows wear performance equal to (new) hardened
sheaves. Rope replacements with the same diameter do not create new wear because
of the graphite that came free working the sheave. In the second instance, a special
manufacturing technique is used to create a higher than standard hardness in the
groove, optimizing the sheave durability.
SERVICE
Ropeblock sheaves have a higher than average low temperature performance, allowing
service down to even -40°C/-40°F. The improved ductility in the Ropeblock sheave
allows better resistance against impact or other unintended blows against objects and
the material grain makes it more crack-resistant.
Contact us or our sales representatives for information or availability regarding your
application.
ROPEBLOCK B.V.
Ropeblock B.V. is a leading engineering and manufacturing specialist for the lifting and
wire rope industry in many aspects. Our mechanical lifting and hoisting components
are used in practically all sectors involving machinery for lifting, hoisting, and transporting
materials. They are used in critical machinery such as in ports, on ships and offshore
platforms, construction, mining, dredging and in heavy industry, operating success-
fully on all continents, both underwater as well as on today’s highest skyscrapers.
Many of the leading crane and wire rope manufacturers in the world are familiar with
our products and our standard of quality and safety. Exports from the Netherlands
represent 95% of our sales, and our products comply with the very demanding
international regulations and standards.
www.ropeblock.com
Ropeblock sheaves - Engineered for durability
www.ropeblock.com
Ropeblock B.V.
PO Box 391 I NL-7570 AJ Oldenzaal I The Netherlands
T +31 (0)541 532 300 I F +31 (0)541 536 575 I E sales@ropeblock.com
Copyright©2016
Published by Ropeblock B.V. All rights reserved - 0916/VV/SCRA

2. R
E
d
F
D3
D1
D2
G
The most advanced sheave -
wire rope interaction available!
In the past two decades, Ropeblock has put sheaves on
the market that we believed to perform the best in wire
rope interaction and would generate the most Cycle
Bends Over Sheave (CBOS) in its numerous applications.
Use in countless construction, cargo handling, offshore
and industry applications in over these twenty years,
continuously confirmed this belief in the form of our
(OEM) customer feedback.
CYCLE BENDS OVER SHEAVE IN A TWISTED STATE
When a wire rope is bent over a sheave, the wire rope
is fatigued. Since university studies in 2015, it has been
known that a wire rope is even more fatigued when it
is bent over a sheave in a twisted state. These university
studies show durability reductions in commonly seen
twisted states of wire rope of up to 70% in the most
commonly used rotation resistant ropes.
FLEET ANGLES AND TWIST
In nearly all crane applications, fleet
angles (the angle of attack of the wire
rope on to the sheave groove) are the
mainreasonfortheintroductionoftwist
in the wire rope while you are working
the crane. The type of operation ran is of
great influence on the amount of twist
generated in the system.
BLOCK ROTATION OR CABLING
Wire ropes come with their type designated torque factor.
Under tension, this implies the end of the wire rope wants
to rotate when free (e.g. with a swivel), but cannot when
fixed directly to the crane. The additional twist as a result
of the fleet angles generates extra torsion. When the
accumulated twist in your system is released between
the tip of the crane and the lower block, it may at one
point result in block rotation. The overtime buildup of
twist has then tipped the balance of a stable tackle to
a tackle with cabling.
WIRE ROPE - SHEAVE INTERACTION
A large part of the amount of wire rope twist is determined
by the coefficient of friction between the wire rope and
the sheave. In the older literature, plastic sheaves showed
the highest friction and the most twist. Metal sheaves
would perform better. Ropeblock introduced two decades
ago a metal sheave with dry lubrication in the form of
graphite leaving properties (in a function similar to bronze
bearings with graphite nodes) to lower the coefficient of
friction while it works with the wire rope and promotes
sliding of the wire rope, rather than twisting it.
CONFIRMATION BY COMPARISON TESTING
Because of the recent further study where the twisted
state of a wire rope would reduce longevity significantly,
Ropeblock launched a comparison investigation under
the optimal groove throat angle.
Here, it shows that the Ropeblock sheave performs 40%
betteragainsttwistthanthesamesizeandgeometryplastic
sheave and approx. 25% better against twist compared to
a normal steel sheave of a similar size and geometry.
Plastic Steel (worked)Steel Ropeblock (worked)RopeblockPlastic (worked)
0
5,0
Angleofturnsabsolute
10,0
15,0
20,0
25,0
30,0
35,0