SAMSON ROPE
Excerpts from the 1996-97 Samson Ropes Product Brochure.
| For well over 100 years, Samson has been the leader in developing and manufacturing braided ropes. During the 1800's, Samson perfected the unique concept of incorporating reinforcement cores within braids to significantly enhance product performance. In 1957, the engineers at Samson took this innovation another step forward and developed the modern synthetic double braid. By combining newly developed fibers in their patented construction, ropes could be engineered with those characteristics critical to the applications for which they were designed. Performance factors, such as strength, elongation, flexibility, and abrasion resistance, could now be engineered into the rope. |
With this heritage, it's no wonder that Samson ropes excel in workplaces
as tough as those encountered by the professional arborist. Samson's line of Tree Ropes
are specifically engineered to maximize performance where ropes are expected to provide a
margin of security for climbers working in the tree, running against bark and through
crotches, support and control of descending loads, while providing a reasonable working
life.
The most complete line of products in the industry.. Samson's
line of Arborist ropes includes both climbing and bull ropes, 12 and 16 strand braided
constructions, double braided, and three strand twisted ropes. Each construction and
combination of fibers offers its own mix of performance characteristics. Strength,
elongation characteristics, abrasion resistance, and snag resistance are all factors to
consider in choosing the appropriate line for a given task.
To help make the decision making process less intimidating, this catalog
has been designed as a complete reference on Samson Arborist products. In it you will find
specifications for each product, which allows comparison between products to ensure that
the product chosen will function in its role in the workplace. In addition, we have
included reference materials on usage and inspection techniques for ropes in general.
In order to promote safety on the job site, and ensure that our products
are used most effectively, Samson has teamed up with the arborist community to promote and
provide current information on effective and safe climbing techniques. The section
beginning on page 12 presents information on basic techniques, rigging and knots, as well
as a rope inspection and retirement guide to assist the arborist in assessing the
condition of his equipment. While not intended to be a comprehensive guide to this
demanding aspect of the arborists profession, it will introduce a few basic concepts, and
hopefully encourage the search for more information on this critical aspect of the
arborist's occupation.
Our commitment to the arborist industry is evident on two levels. First,
to each and every arborist, by supplying a wide variety of high quality products that can
be trusted to provide consistent performance. Your performance, as well as your safety,
depends on the choices you make in selecting the tools you work with. At Samson, our goal
is to make our products your first choice for quality and economy. Along with our
distributors and dealers, we are committed to providing information which helps you use
our products in a safe and effective manner. This catalog, as well as other important
publications, contain critical safety and usage information. Second, our commitment is
directed toward the professional advancement of the industry.
Our support of effective training programs like those sponsored by the
NAA and ISA, "ArborGames" and others is critical to informing and educating
arborists everywhere. Our support and attendance at trade exhibitions as well as
"hands on" seminars helps us better understand your needs and preferences. This
process of feedback and involvement helps everyone and improves our value to the industry
as well as yours.
NEW ROPE TENSILE STRENGTHS
New rope tensile strengths are based on tests of new and unused rope of
standard construction in accordance with manufacturer's Standard Test Methods. It can be
expected that strengths will decrease as soon as a rope is put into use. Because of the
wide range of rope use, changes in rope conditions, exposure to the many factors affecting
rope behavior, and the possibility of risk to life and property, it is impossible to cover
all aspects of rope applications or to make blanket recommendations as to working loads.
WORKING LOADS
Working loads are for rope in good condition with appropriate splices,
in non-critical applications and under normal service conditions. Working loads are based
on a percentage of the approximate breaking strength of new and unused rope of current
manufacture. For our arborist rope products, when used under normal conditions, the
working load percentage is 10% of published strengths. Normal working loads do not
cover dynamic conditions such as shock loads or sustained loads, nor do they cover
where life, limb or valuable property are involved. In these cases a lower working load
must be used.
A higher working load may be selected only with expert knowledge of
conditions and professional estimates of risk, if the rope has been inspected and found to
be in good condition, and if the rope has not been subject to dynamic loading (such as
sudden drops, snubs or pickups), excessive use, elevated temperatures, or extended periods
under load.
NORMAL WORKING LOADS
Normal working loads are not applicable when rope has been subject to
dynamic loading. Whenever a load is picked up, stopped, moved or swung there is an
increased. force due to dynamic loading. The more rapidly or suddenly such actions occur,
the greater the increase will be. In extreme cases, the force put on the rope may be two,
three, or even more timess the normal load involved, Examples could be ropes used as a tow
line, picking up a load on a slack line, or using rope to stop a falling object. Dynamic
effects are greater on a low elongation rope such as polyester than on a high elongation
rope such as nylon, and greater on a short rope than on a long one. Therefore, in all such
applications normal working loads as given do not apply, for more information see pages
14-16. (in the Samson Products Catalog)
A heavily used rope will often become compacted or hard which indicates
reduced strength. The rope should be discarded if this condition exists.
AVOID ALL ABRASIVE CONDITIONS
All rope will be severely damaged if subjected to rough surfaces or
sharp edges. Chocks, bitts, winches, drums and other surfaces must be kept in good
condition and free of burrs and rust. Pulleys must be free to rotate and should be of
proper size to avoid excessive wear.
AVOID CHEMICAL EXPOSURE
Rope is subject to damage by chemicals. Consult the manufacturer for
specific chemical exposure, such as solvents, acids, and alkalies. Consult the
manufacturer for recommendations when a rope will be used where chemical exposure (either
fumes or actual contact) can occur.
AVOID OVERHEATING
Heat can seriously affect the strength of synthetic ropes. The
temperatures at which 50 percent strength loss can occur are: Polypropylene 250 degrees F,
Nylon 350 F, Polyester 350 F When using rope where the temperature exceeds these levels
(or if it is too hot to hold), consult the manufacturer for recommendations as to the size
and type of rope for the proposed continuous heat exposure conditions. When using ropes on
a capstan or winch, care should be exercised to avoid surging while the capstan or
winch head is rotating. The friction from this slippage causes localized overhearing which
can melt or fuse synthetic fibers, resulting in severe loss of tensile strength.
STORAGE
All rope should be stored clean, dry, out of direct sunlight, and away
from extreme heat. It should be kept off the floor on racks to provide ventilation
underneath. Never store on a concrete or dirt floor, and under no circumstances should
cordage and acid or alkalies be kept in the same vicinity. Some synthetic rope (in
particular polypropylene or polyethylene) may be severely weakened by prolonged exposure
to ultraviolet rays unless specifically stabilized and/or pigmented to increase LTV
resistance. UV degradation is indicated by discoloration and the presence of splinters and
slivers on the surface of the rope.
DYNAMIC LOADING
For dynamic loading applications involving severe exposure conditions,
or for recommendations on special applications, consult the manufacturer, for more
information see page 15.
WINCHING LINES
Braided rope can develop a twist when constantly used an a winch. This
makes handling more difficult and the rope should be relaxed and rotated in the opposite
direction to remove a twist, To avoid this condition the direction of turns over the winch
should be alternated regularly.
SPLICING AND KNOTS
Splices should be used instead of knots whenever possible because knots can decrease rope strength up to 50%.
When splices are used, always use the manufacturer's recommended
splicing procedures. When knots are used, be sure to take into consideration the knot's
corresponding reduction to the rope strength and adjust your working load accordingly. For
more information please see the knots and Rigging section, pages 17 - 19.
ROPE INSPECTION
Avoid using, rope that shows signs of aging and wear. If in doubt,
destroy the used rope.
No type of visual inspection can be guaranteed to accurately and
precisely determine the actual residual strength. When the fibers show wear in any given
area, the rope should be re-spliced, downgraded, or replaced, Check the line regularly
for frayed strands and broken yarns. Pulled strands should be re-threaded into the rope if
possible. A pulled strand can snag on a foreign object during rope operation.
Both outer and inner rope fibers contribute to the strength of the rope.
When either is worn, the rope is naturally weakened. Open the strands of the rope and look
for powdered fiber, which is one sign of internal wear.
These excerpts are taken directly from the Samson Rope 1996-97 brochure
with their permission. There may be references to pages in the text. Please understand to
find these you must contact them for the entire brochure. We are going to be running the
brochure information over the next few newsletter issues for you education. This is a very
informative piece.
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