![Constriction of rope](https://upload.wikimedia.org/wikipedia/commons/9/9e/Constriction_of_rope.png)
A rope is a group of
yarn
Yarn is a long continuous length of interlocked fibres, used in sewing, crocheting, knitting, weaving, embroidery, ropemaking, and the production of textiles. Thread is a type of yarn intended for sewing by hand or machine. Modern manufact ...
s,
plies,
fibre
Fiber or fibre (from la, fibra, links=no) is a natural or artificial substance that is significantly longer than it is wide. Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorporate ...
s, or strands that are twisted or
braid
A braid (also referred to as a plait) is a complex structure or pattern formed by interlacing two or more strands of flexible material such as textile yarns, wire, or hair.
The simplest and most common version is a flat, solid, three-strande ...
ed together into a larger and stronger form. Ropes have
tensile strength
Ultimate tensile strength (UTS), often shortened to tensile strength (TS), ultimate strength, or F_\text within equations, is the maximum stress that a material can withstand while being stretched or pulled before breaking. In brittle materials t ...
and so can be used for dragging and lifting. Rope is thicker and stronger than similarly constructed cord,
string, and
twine
Twine is a strong Thread (yarn), thread, light String (cord), string or cord composed of two or more thinner strands twisted, and then twisted together (Plying, plied). The strands are plied in the opposite direction to that of their twist, whic ...
.
Construction
![SuperMacro Rope](https://upload.wikimedia.org/wikipedia/commons/f/f7/SuperMacro_Rope.JPG)
Rope may be constructed of any long, stringy, fibrous material, but generally is constructed of certain
natural
Nature, in the broadest sense, is the physical world or universe. "Nature" can refer to the phenomena of the physical world, and also to life in general. The study of nature is a large, if not the only, part of science. Although humans are p ...
or
synthetic fibres.
Synthetic fibre ropes are significantly stronger than their natural fibre counterparts, they have a higher
tensile strength
Ultimate tensile strength (UTS), often shortened to tensile strength (TS), ultimate strength, or F_\text within equations, is the maximum stress that a material can withstand while being stretched or pulled before breaking. In brittle materials t ...
, they are more resistant to rotting than ropes created from natural fibres, and they can be made to float on water.
But synthetic ropes also possess certain disadvantages, including slipperiness, and some can be damaged more easily by
UV light
Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nm (with a corresponding frequency around 30 PHz) to 400 nm (750 THz), shorter than that of visible light, but longer than X-rays. UV radiation i ...
.
Common natural fibres for rope are
Manila hemp
Manila hemp, also known as abacá, is a type of buff-colored fiber obtained from ''Musa textilis'' (a relative of edible bananas), which is likewise called Manila hemp as well as abacá. It is mostly used for pulping for a range of uses, inclu ...
,
hemp
Hemp, or industrial hemp, is a botanical class of ''Cannabis sativa'' cultivars grown specifically for industrial or medicinal use. It can be used to make a wide range of products. Along with bamboo, hemp is among the fastest growing plants o ...
,
linen
Linen () is a textile made from the fibers of the flax plant.
Linen is very strong, absorbent, and dries faster than cotton. Because of these properties, linen is comfortable to wear in hot weather and is valued for use in garments. It also ...
,
cotton
Cotton is a soft, fluffy staple fiber that grows in a boll, or protective case, around the seeds of the cotton plants of the genus ''Gossypium'' in the mallow family Malvaceae. The fiber is almost pure cellulose, and can contain minor perce ...
,
coir
Coir (), also called coconut fibre, is a natural fibre extracted from the outer husk of coconut and used in products such as floor mats, doormats, brushes, and mattresses. Coir is the fibrous material found between the hard, internal shell ...
,
jute
Jute is a long, soft, shiny bast fiber that can be spun into coarse, strong threads. It is produced from flowering plants in the genus ''Corchorus'', which is in the mallow family Malvaceae. The primary source of the fiber is ''Corchorus olit ...
,
straw
Straw is an agricultural byproduct consisting of the dry stalks of cereal plants after the grain and chaff have been removed. It makes up about half of the yield of cereal crops such as barley, oats, rice, rye and wheat. It has a number ...
, and
sisal
Sisal (, ) (''Agave sisalana'') is a species of flowering plant native to southern Mexico, but widely cultivated and naturalized in many other countries. It yields a stiff fibre used in making rope and various other products. The term sisal ma ...
. Synthetic fibres in use for rope-making include
polypropylene
Polypropylene (PP), also known as polypropene, is a thermoplastic polymer used in a wide variety of applications. It is produced via chain-growth polymerization from the monomer propylene.
Polypropylene
belongs to the group of polyolefins and ...
,
nylon
Nylon is a generic designation for a family of synthetic polymers composed of polyamides ( repeating units linked by amide links).The polyamides may be aliphatic or semi-aromatic.
Nylon is a silk-like thermoplastic, generally made from petro ...
,
polyester
Polyester is a category of polymers that contain the ester functional group in every repeat unit of their main chain. As a specific material, it most commonly refers to a type called polyethylene terephthalate (PET). Polyesters include natural ...
s (e.g.
PET
A pet, or companion animal, is an animal kept primarily for a person's company or entertainment rather than as a working animal, livestock, or a laboratory animal. Popular pets are often considered to have attractive appearances, intelligence, ...
,
LCP,
Vectran
Vectran is a manufactured fiber, spun from a liquid-crystal polymer (LCP) created by Celanese Corporation and now manufactured by Kuraray. Chemically it is an aromatic polyester produced by the polycondensation of 4-hydroxybenzoic acid and 6-hyd ...
),
polyethylene
Polyethylene or polythene (abbreviated PE; IUPAC name polyethene or poly(methylene)) is the most commonly produced plastic. It is a polymer, primarily used for packaging ( plastic bags, plastic films, geomembranes and containers including bo ...
(e.g.
Dyneema and Spectra),
Aramid
Aramid fibers, short for aromatic polyamide, are a class of heat-resistant and strong synthetic fibers. They are used in aerospace and military applications, for ballistic-rated body armor fabric and ballistic composites, in marine cordage, ma ...
s (e.g.
Twaron
Twaron (a brand name of Teijin Aramid) is a para-aramid. It is a heat-resistant and strong synthetic fibre developed in the early 1970s by the Dutch company Akzo Nobel's division Enka BV, later Akzo Industrial Fibers. The research name of the para ...
,
Technora
Technora is an aramid that is useful for a variety of applications that require high strength or chemical resistance. It is a brand name of the company Teijin Aramid.
Technora was used on January 25, 2004 to suspend the NASA Mars rover Opportunit ...
and
Kevlar
Kevlar (para-aramid) is a strong, heat-resistant synthetic fiber, related to other aramids such as Nomex and Technora. Developed by Stephanie Kwolek at DuPont in 1965, the high-strength material was first used commercially in the early 1970s a ...
) and
acrylics (e.g.
Dralon
Acrylic fibers are synthetic fibers made from a polymer (polyacrylonitrile) with an average molecular weight of ~100,000, about 1900 monomer units. For a fiber to be called "acrylic" in the US, the polymer must contain at least 85% acrylonitri ...
). Some ropes are constructed of mixtures of several fibres or use co-polymer fibres.
Wire rope
Steel wire rope (right hand lang lay)
Wire rope is several strands of metal wire twisted into a helix forming a composite
''rope'', in a pattern known as ''laid rope''. Larger diameter wire rope consists of multiple strands of such laid rope in a ...
is made of steel or other metal alloys. Ropes have been constructed of other fibrous materials such as
silk
Silk is a natural protein fiber, some forms of which can be woven into textiles. The protein fiber of silk is composed mainly of fibroin and is produced by certain insect larvae to form cocoons. The best-known silk is obtained from the coc ...
,
wool
Wool is the textile fibre obtained from sheep and other mammals, especially goats, rabbits, and camelids. The term may also refer to inorganic materials, such as mineral wool and glass wool, that have properties similar to animal wool.
As ...
, and hair, but such ropes are not generally available.
Rayon
Rayon is a semi-synthetic fiber, made from natural sources of regenerated cellulose, such as wood and related agricultural products. It has the same molecular structure as cellulose. It is also called viscose. Many types and grades of viscose f ...
is a regenerated fibre used to make decorative rope.
The twist of the strands in a twisted or braided rope serves not only to keep a rope together, but enables the rope to more evenly distribute tension among the individual strands. Without any twist in the rope, the shortest strand(s) would always be supporting a much higher proportion of the total load.
Size measurement
Because rope has a long history, many systems have been used to specify the size of a rope. In systems that use the inch (
Imperial and US customary measurement systems
The imperial and US customary measurement systems are both derived from an earlier English system of measurement which in turn can be traced back to Ancient Roman units of measurement, and Carolingian and Saxon units of measure.
The US Customa ...
), large ropes over diameter – such as those used on ships – are measured by their circumference in inches; smaller ropes have a nominal diameter based on the circumference divided by three (as a rough approximation of
pi). In the metric system of measurement, the nominal diameter is given in millimetres. The current preferred international standard for rope sizes is to give the mass per unit length, in kilograms per metre. However, even sources otherwise using metric units may still give a "rope number" for large ropes, which is the circumference in inches.
Use
![HK TST Star Ferry Victoria Harbour Mooring Rope](https://upload.wikimedia.org/wikipedia/commons/1/19/HK_TST_Star_Ferry_Victoria_Harbour_Mooring_Rope.JPG)
Rope has been used since
prehistoric
Prehistory, also known as pre-literary history, is the period of human history between the use of the first stone tools by hominins 3.3 million years ago and the beginning of recorded history with the invention of writing systems. The use of ...
times. It is of paramount importance in fields as diverse as
construction
Construction is a general term meaning the art and science to form objects, systems, or organizations,"Construction" def. 1.a. 1.b. and 1.c. ''Oxford English Dictionary'' Second Edition on CD-ROM (v. 4.0) Oxford University Press 2009 and com ...
,
seafaring
Seamanship is the art, knowledge and competence of operating a ship, boat or other craft on water. The'' Oxford Dictionary'' states that seamanship is "The skill, techniques, or practice of handling a ship or boat at sea."
It involves topics a ...
, exploration, sports, theatre, and communications. Many types of
knot
A knot is an intentional complication in cordage which may be practical or decorative, or both. Practical knots are classified by function, including hitches, bends, loop knots, and splices: a ''hitch'' fastens a rope to another object; a ' ...
s have been developed to fasten with rope, join ropes, and utilize rope to generate
mechanical advantage
Mechanical advantage is a measure of the force amplification achieved by using a tool, mechanical device or machine system. The device trades off input forces against movement to obtain a desired amplification in the output force. The model for t ...
.
Pulley
A pulley is a wheel on an axle or shaft that is designed to support movement and change of direction of a taut cable or belt, or transfer of power between the shaft and cable or belt. In the case of a pulley supported by a frame or shell that ...
s can redirect the pulling force of a rope in another direction, multiply its lifting or pulling power, and distribute a load over multiple parts of the same rope to increase safety and decrease wear.
Winch
A winch is a mechanical device that is used to pull in (wind up) or let out (wind out) or otherwise adjust the tension of a rope or wire rope (also called "cable" or "wire cable").
In its simplest form, it consists of a spool (or drum) attache ...
es and
capstans are machines designed to pull ropes.
History
![Ancient Egypt rope manufacture](https://upload.wikimedia.org/wikipedia/commons/2/20/Ancient_Egypt_rope_manufacture.jpg)
The use of ropes for hunting, pulling, fastening, attaching, carrying, lifting, and climbing dates back to
prehistoric
Prehistory, also known as pre-literary history, is the period of human history between the use of the first stone tools by hominins 3.3 million years ago and the beginning of recorded history with the invention of writing systems. The use of ...
times. It is likely that the earliest "ropes" were naturally occurring lengths of plant fibre, such as vines, followed soon by the first attempts at twisting and braiding these strands together to form the first proper ropes in the modern sense of the word. The earliest evidence of suspected rope is a very small fragment of three-ply cord from a Neanderthal site dated 50,000 years ago. This item was so small, it was only discovered and described with the help of a high power microscope. It is slightly thicker than the average thumb-nail, and would not stretch from edge-to-edge across a little finger-nail. There are other ways fibres can twist in nature, without deliberate construction.
A 40,000-year-old tool found in
Hohle Fels
The ''Hohle Fels'' () (also ''Hohlefels'', ''Hohler Fels'', German for "hollow rock") is a cave in the Swabian Jura of Germany that has yielded a number of important archaeological finds dating from the Upper Paleolithic. Artifacts found in the ...
cave in south-western Germany was identified in 2020 as very likely to be a tool for making rope. It is a strip of mammoth ivory with four holes drilled through it. Each hole is lined with precisely cut spiral incisions.
The grooves on three of the holes spiral in a clockwise direction from each side of the strip. The grooves on one hole spiral clockwise on one side, but counter-clockwise from the other side. Plant fibres would have been fed through the holes and the tool twisted, creating a single ply yarn. The spiral incisions would have tended to keep the fibres in place.
[ Article has photograph of the Hohle Fels rope-making tool.] But the incisions cannot impart any twist to the fibres pulled through the holes.
Other 15,000-year-old objects with holes with spiral incisions, made from reindeer antler, found across Europe are thought to have been used to manipulate ropes, or perhaps some other purpose. They were originally named "
batons", and thought possibly to have been carried as badges of rank.
[
Impressions of cordage found on ]fired clay
Fire clay is a range of refractory clays used in the manufacture of ceramics, especially fire brick. The United States Environmental Protection Agency defines fire clay very generally as a "mineral aggregate composed of hydrous silicates of alumin ...
provide evidence of string and rope-making technology in Europe dating back 28,000 years. Fossil
A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved ...
ized fragments of "probably two-ply laid rope of about diameter" were found in one of the caves at Lascaux
Lascaux ( , ; french: Grotte de Lascaux , "Lascaux Cave") is a network of caves near the village of Montignac, in the department of Dordogne in southwestern France. Over 600 parietal wall paintings cover the interior walls and ceilings of ...
, dating to approximately 15,000 BC.[J.C. Turner and P. van de Griend (ed.), ''The History and Science of Knots'' (Singapore: World Scientific, 1996), 14.]
The ancient Egyptians were probably the first civilization to develop special tools to make rope. Egyptian rope dates back to 4000 to 3500 BC and was generally made of water reed fibres. Other rope in antiquity was made from the fibres of date palm
''Phoenix dactylifera'', commonly known as date or date palm, is a flowering plant species in the palm family, Arecaceae, cultivated for its edible sweet fruit called dates. The species is widely cultivated across northern Africa, the Middle Eas ...
s, flax
Flax, also known as common flax or linseed, is a flowering plant, ''Linum usitatissimum'', in the family Linaceae. It is cultivated as a food and fiber crop in regions of the world with temperate climates. Textiles made from flax are known in ...
, grass
Poaceae () or Gramineae () is a large and nearly ubiquitous family of monocotyledonous flowering plants commonly known as grasses. It includes the cereal grasses, bamboos and the grasses of natural grassland and species cultivated in lawns an ...
, papyrus
Papyrus ( ) is a material similar to thick paper that was used in ancient times as a writing surface. It was made from the pith of the papyrus plant, '' Cyperus papyrus'', a wetland sedge. ''Papyrus'' (plural: ''papyri'') can also refer to a ...
, leather
Leather is a strong, flexible and durable material obtained from the tanning, or chemical treatment, of animal skins and hides to prevent decay. The most common leathers come from cattle, sheep, goats, equine animals, buffalo, pigs and hogs, ...
, or animal hair. The use of such ropes pulled by thousands of workers allowed the Egyptians
Egyptians ( arz, المَصرِيُون, translit=al-Maṣriyyūn, ; arz, المَصرِيِين, translit=al-Maṣriyyīn, ; cop, ⲣⲉⲙⲛ̀ⲭⲏⲙⲓ, remenkhēmi) are an ethnic group native to the Nile, Nile Valley in Egypt. Egyptian ...
to move the heavy stones required to build their monuments. Starting from approximately 2800 BC, rope made of hemp
Hemp, or industrial hemp, is a botanical class of ''Cannabis sativa'' cultivars grown specifically for industrial or medicinal use. It can be used to make a wide range of products. Along with bamboo, hemp is among the fastest growing plants o ...
fibres was in use in China. Rope and the craft of rope making spread throughout Asia, India, and Europe over the next several thousand years.
From the Middle Ages until the 18th century, in Europe ropes were constructed in ropewalk
A ropewalk is a long straight narrow lane, or a covered pathway, where long strands of material are laid before being twisted into rope. Due to the length of some ropewalks, workers may use bicycles to get from one end to the other.
Many ropew ...
s, very long buildings where strands the full length of the rope were spread out and then ''laid up'' or twisted together to form the rope. The cable length was thus set by the length of the available rope walk. This is related to the unit of length termed ''cable length
A cable length or length of cable is a nautical unit of measure equal to one tenth of a nautical mile or approximately 100 fathoms. Owing to anachronisms and varying techniques of measurement, a cable length can be anywhere from 169 to 220 metres ...
''. This allowed for long ropes of up to long or longer to be made. These long ropes were necessary in shipping as short ropes would require splicing to make them long enough to use for sheets
A bed sheet is a rectangular piece of cloth used either singly or in a pair as bedding, which is larger in length and width than a mattress, and which is placed immediately above a mattress or bed, but below blankets and other bedding (such as ...
and halyards
In sailing, a halyard or halliard is a line (rope) that is used to hoist a ladder, sail, flag or yard. The term ''halyard'' comes from the phrase "to haul yards". Halyards, like most other parts of the running rigging, were classically made of n ...
. The strongest form of splicing is the short splice, which doubles the cross-sectional area of the rope at the area of the splice, which would cause problems in running the line through pulleys. Any splices narrow enough to maintain smooth running would be less able to support the required weight.
Leonardo da Vinci
Leonardo di ser Piero da Vinci (15 April 14522 May 1519) was an Italian polymath of the High Renaissance who was active as a painter, Drawing, draughtsman, engineer, scientist, theorist, sculptor, and architect. While his fame initially res ...
drew sketches of a concept for a ropemaking machine, but it was never built. Remarkable feats of construction were accomplished using rope but without advanced technology: In 1586, Domenico Fontana
Domenico Fontana (154328 June 1607) was an Italian architect of the late Renaissance, born in today's Ticino. He worked primarily in Italy, at Rome and Naples.
Biography
He was born at Melide, a village on the Lake Lugano, at that time joint p ...
erected the 327 ton obelisk
An obelisk (; from grc, ὀβελίσκος ; diminutive of ''obelos'', " spit, nail, pointed pillar") is a tall, four-sided, narrow tapering monument which ends in a pyramid-like shape or pyramidion at the top. Originally constructed by Anc ...
on Rome's Saint Peter's Square
Saint Peter's Square ( la, Forum Sancti Petri, it, Piazza San Pietro ,) is a large plaza located directly in front of St. Peter's Basilica in Vatican City, the papal enclave inside Rome, directly west of the neighborhood (rione) of Borgo. Bot ...
with a concerted effort of 900 men, 75 horses, and countless pulleys and meters of rope. By the late 18th century several working machines had been built and patented.
Some rope is still made from natural fibres, such as coir
Coir (), also called coconut fibre, is a natural fibre extracted from the outer husk of coconut and used in products such as floor mats, doormats, brushes, and mattresses. Coir is the fibrous material found between the hard, internal shell ...
and sisal
Sisal (, ) (''Agave sisalana'') is a species of flowering plant native to southern Mexico, but widely cultivated and naturalized in many other countries. It yields a stiff fibre used in making rope and various other products. The term sisal ma ...
, despite the dominance of synthetic fibre
Synthetic fibers or synthetic fibres (in British English; see spelling differences) are fibers made by humans through chemical synthesis, as opposed to natural fibers that are directly derived from living organisms, such as plants (like cotton) ...
s such as nylon
Nylon is a generic designation for a family of synthetic polymers composed of polyamides ( repeating units linked by amide links).The polyamides may be aliphatic or semi-aromatic.
Nylon is a silk-like thermoplastic, generally made from petro ...
and polypropylene
Polypropylene (PP), also known as polypropene, is a thermoplastic polymer used in a wide variety of applications. It is produced via chain-growth polymerization from the monomer propylene.
Polypropylene
belongs to the group of polyolefins and ...
, which have become increasingly popular since the 1950s.
Nylon was discovered in the late 1930s and was first introduced into fiber ropes during World War II. Indeed, the first synthetic fiber ropes were small braided parachute cords and three-strand tow ropes for gliders, made of nylon during World War II.
Mendel I 016 r.jpg, A ropemaker at work,
German Ropemaker, around 1460-1480.png, A German ropemaker,
Turku Medieval Markets, twisting rope.jpg, Public demonstration of historical ropemaking technique
MaryRose-rope fragment.JPG, A piece of preserved rope found on board the 16th century carrack
A carrack (; ; ; ) is a three- or four- masted ocean-going sailing ship that was developed in the 14th to 15th centuries in Europe, most notably in Portugal. Evolved from the single-masted cog, the carrack was first used for European trade fr ...
''Mary Rose
The ''Mary Rose'' (launched 1511) is a carrack-type warship of the English Tudor navy of King Henry VIII. She served for 33 years in several wars against France, Scotland, and Brittany. After being substantially rebuilt in 1536, she saw her l ...
''
Repslagarbanan 1-Karlskrona.JPG, A ropewalk in Karlskrona
Karlskrona (, , ) is a locality and the seat of Karlskrona Municipality, Blekinge County, Sweden with a population of 66,675 in 2018. It is also the capital of Blekinge County. Karlskrona is known as Sweden's only baroque city and is host to Swed ...
, Sweden
Styles of rope
Laid or twisted rope
Laid rope, also called twisted rope, is historically the prevalent form of rope, at least in modern Western
Western may refer to:
Places
*Western, Nebraska, a village in the US
*Western, New York, a town in the US
*Western Creek, Tasmania, a locality in Australia
*Western Junction, Tasmania, a locality in Australia
*Western world, countries that id ...
history. Common twisted rope generally consists of three strands and is normally right-laid, or given a final right-handed twist. The ISO 2
ISO 2 is an international standard for direction of twist designation for yarns, complex yarns, slivers, slubbings, rovings, cordage, and related products.
The standard uses capital letters S and Z to indicate the direction of twist, as su ...
standard uses the uppercase letters and to indicate the two possible directions of twist, as suggested by the direction of slant of the central portions of these two letters. The handedness
In human biology, handedness is an individual's preferential use of one hand, known as the dominant hand, due to it being stronger, faster or more Fine motor skill, dextrous. The other hand, comparatively often the weaker, less dextrous or sim ...
of the twist is the direction of the twists as they progress away from an observer. Thus Z-twist rope is said to be right-handed
In human biology, handedness is an individual's preferential use of one hand, known as the dominant hand, due to it being stronger, faster or more dextrous. The other hand, comparatively often the weaker, less dextrous or simply less subjecti ...
, and S-twist to be left-handed.
Twisted ropes are built up in three steps. First, fibre
Fiber or fibre (from la, fibra, links=no) is a natural or artificial substance that is significantly longer than it is wide. Fibers are often used in the manufacture of other materials. The strongest engineering materials often incorporate ...
s are gathered and spun
''Spun'' is a 2002 American black comedy crime drama film directed by Jonas Åkerlund from an original screenplay by William De Los Santos and Creighton Vero, based on three days of De Los Santos's life in the Eugene, Oregon, drug subculture. The ...
into yarn
Yarn is a long continuous length of interlocked fibres, used in sewing, crocheting, knitting, weaving, embroidery, ropemaking, and the production of textiles. Thread is a type of yarn intended for sewing by hand or machine. Modern manufact ...
s. A number of these yarns are then formed into strands by twisting. The strands are then twisted together to lay the rope. The twist of the yarn is opposite to that of the strand, and that in turn is opposite to that of the rope. It is this counter-twist, introduced with each successive operation, which holds the final rope together as a stable, unified object.
Traditionally, a three strand laid rope is called a ''plain-'' or ''hawser
Hawser () is a nautical term for a thick cable or rope used in mooring or towing a ship.
A hawser passes through a hawsehole, also known as a cat hole, located on the hawse.The American Heritage Dictionary of the English Language, third edition, ...
-laid'', a four strand rope is called ''shroud-laid'', and a larger rope formed by counter-twisting three or more multi-strand ropes together is called ''cable-laid''. Cable-laid rope is sometimes clamped to maintain a tight counter-twist rendering the resulting cable
Cable may refer to:
Mechanical
* Nautical cable, an assembly of three or more ropes woven against the weave of the ropes, rendering it virtually waterproof
* Wire rope, a type of rope that consists of several strands of metal wire laid into a hel ...
virtually waterproof. Without this feature, deep water sailing (before the advent of steel chains and other lines) was largely impossible, as any appreciable length of rope for anchoring or ship to ship transfers, would become too waterlogged – and therefore too heavy – to lift, even with the aid of a capstan or windlass.
One property of laid rope is partial untwisting when used. This can cause spinning of suspended loads, or stretching
Stretching is a form of physical exercise in which a specific muscle or tendon (or muscle group) is deliberately flexed or stretched in order to improve the muscle's felt elasticity and achieve comfortable muscle tone. The result is a feeling ...
, kinking, or hockling of the rope itself. An additional drawback of twisted construction is that every fibre is exposed to abrasion numerous times along the length of the rope. This means that the rope can degrade to numerous inch-long fibre fragments, which is not easily detected visually.
Twisted ropes have a preferred direction for coiling. Normal right-laid rope should be coiled clockwise, to prevent kinking. Coiling this way imparts a twist to the rope. Rope of this type must be bound
Bound or bounds may refer to:
Mathematics
* Bound variable
* Upper and lower bounds, observed limits of mathematical functions
Physics
* Bound state, a particle that has a tendency to remain localized in one or more regions of space
Geography
*B ...
at its ends by some means to prevent untwisting.
Braided rope
While rope may be made from three or more strands, modern braided rope consists of a braided (tubular) jacket over strands of fibre (these may also be braided). Some forms of braided rope with untwisted cores have a particular advantage; they do not impart an additional twisting force when they are stressed. The lack of added twisting forces is an advantage when a load is freely suspended, as when a rope is used for rappelling
Abseiling ( ; ), also known as rappelling ( ; ), is the controlled descent of a steep slope, such as a rock face, by moving down a rope. When abseiling the person descending controls their own movement down the rope, in contrast to low ...
or to suspend an arborist
An arborist, tree surgeon, or (less commonly) arboriculturist, is a professional in the practice of arboriculture, which is the cultivation, management, and study of individual trees, shrubs, vines, and other perennial woody plants in dendrolo ...
. Other specialized cores reduce the shock from arresting a fall when used as a part of a personal or group safety system.
Braid
A braid (also referred to as a plait) is a complex structure or pattern formed by interlacing two or more strands of flexible material such as textile yarns, wire, or hair.
The simplest and most common version is a flat, solid, three-strande ...
ed ropes are generally made from nylon
Nylon is a generic designation for a family of synthetic polymers composed of polyamides ( repeating units linked by amide links).The polyamides may be aliphatic or semi-aromatic.
Nylon is a silk-like thermoplastic, generally made from petro ...
, polyester
Polyester is a category of polymers that contain the ester functional group in every repeat unit of their main chain. As a specific material, it most commonly refers to a type called polyethylene terephthalate (PET). Polyesters include natural ...
, polypropylene
Polypropylene (PP), also known as polypropene, is a thermoplastic polymer used in a wide variety of applications. It is produced via chain-growth polymerization from the monomer propylene.
Polypropylene
belongs to the group of polyolefins and ...
or high performance fibres such as high modulus polyethylene (HMPE) and aramid. Nylon is chosen for its strength and elastic stretch properties. However, nylon absorbs water and is 10–15% weaker when wet. Polyester is about 90% as strong as nylon but stretches less under load and is not affected by water. It has somewhat better UV resistance, and is more abrasion resistant. Polypropylene is preferred for low cost and light weight (it floats on water) but it has limited resistance to ultraviolet
Ultraviolet (UV) is a form of electromagnetic radiation with wavelength from 10 nanometer, nm (with a corresponding frequency around 30 Hertz, PHz) to 400 nm (750 Hertz, THz), shorter than that of visible light, but longer than ...
light, is susceptible to friction and has a poor heat resistance.
Braided ropes (and objects like garden hoses, fibre optic
An optical fiber, or optical fibre in Commonwealth English, is a flexible, transparent fiber made by drawing glass (silica) or plastic to a diameter slightly thicker than that of a human hair. Optical fibers are used most often as a means to ...
or coaxial
In geometry, coaxial means that several three-dimensional linear or planar forms share a common axis. The two-dimensional analog is ''concentric''.
Common examples:
A coaxial cable is a three-dimensional linear structure. It has a wire conduc ...
cables, etc.) that have no ''lay'' (or inherent twist) uncoil better if each alternate loop is twisted in the opposite direction, such as in figure-eight coils, where the twist reverses regularly and essentially cancels out.
Single braid consists of an even number of strands, eight or twelve being typical, braided into a circular pattern with half of the strands going clockwise and the other half going anticlockwise. The strands can interlock with either twill
Twill is a type of textile weave with a pattern of diagonal parallel ribs. It is one of three fundamental types of textile weaves along with plain weave and satin. It is made by passing the weft thread over one or more warp threads then under ...
or plain weave
Plain weave (also called tabby weave, linen weave or taffeta weave) is the most basic of three fundamental types of textile weaving, weaves (along with satin weave and twill). It is strong and hard-wearing, and is used for fashion and furnishin ...
. The central void may be large or small; in the former case the term ''hollow braid'' is sometimes preferred.
Double braid, also called braid on braid, consists of an inner braid filling the central void in an outer braid, that may be of the same or different material. Often the inner braid fibre is chosen for strength while the outer braid fibre is chosen for abrasion resistance.
In solid braid, the strands all travel the same direction, clockwise or anticlockwise, and alternate between forming the outside of the rope and the interior of the rope. This construction is popular for general purpose utility rope but rare in specialized high performance line.
Kernmantle rope
Kernmantle rope () is rope constructed with its interior core protected by a woven exterior sheath designed to optimize strength, durability, and flexibility. The core fibers provide the tensile strength of the rope, while the sheath protects the ...
has a core (kern) of long twisted fibres in the center, with a braided outer sheath or mantle of woven
Woven fabric is any textile formed by weaving. Woven fabrics are often created on a loom, and made of many threads woven on a warp and a weft. Technically, a woven fabric is any fabric made by interlacing two or more threads at right angles to on ...
fibres. The kern provides most of the strength (about 70%), while the mantle protects the kern and determines the handling properties of the rope (how easy it is to hold, to tie knots in, and so on). In dynamic climbing line, core fibres are usually twisted to make the rope more elastic. Static kernmantle ropes are made with untwisted core fibres and tighter braid, which causes them to be stiffer in addition to limiting the stretch.
Other types
Plaited rope is made by braiding twisted strands, and is also called ''square braid''. It is not as round as twisted rope and coarser to the touch. It is less prone to kinking than twisted rope and, depending on the material, very flexible and therefore easy to handle and knot. This construction exposes all fibres as well, with the same drawbacks as described above. Brait rope is a combination of braided and plaited, a non-rotating alternative to laid three-strand ropes. Due to its excellent energy-absorption characteristics, it is often used by arborist
An arborist, tree surgeon, or (less commonly) arboriculturist, is a professional in the practice of arboriculture, which is the cultivation, management, and study of individual trees, shrubs, vines, and other perennial woody plants in dendrolo ...
s. It is also a popular rope for anchoring and can be used as mooring warps. This type of construction was pioneered by Yale Cordage.
Endless winding rope is made by winding single strands of high-performance yarns around two end terminations until the desired break strength or stiffness has been reached. This type of rope (often specified as cable to make the difference between a braided or twined construction) has the advantage of having no construction stretch as is the case with above constructions. Endless winding is pioneered by SmartRigging and FibreMax.
Rock climbing
The sport of rock climbing
Rock climbing is a sport in which participants climb up, across, or down natural rock formations. The goal is to reach the summit of a formation or the endpoint of a usually pre-defined route without falling. Rock climbing is a physically and ...
uses what is termed "dynamic" rope, an elastic rope which stretches under load to absorb the energy generated in arresting a fall without creating forces high enough to injure the climber. Such ropes are of kernmantle
Kernmantle rope () is rope constructed with its interior core protected by a woven exterior sheath designed to optimize strength, durability, and flexibility. The core fibers provide the tensile strength of the rope, while the sheath protects the ...
construction, as described below
Below may refer to:
*Earth
*Ground (disambiguation)
*Soil
*Floor
*Bottom (disambiguation)
Bottom may refer to:
Anatomy and sex
* Bottom (BDSM), the partner in a BDSM who takes the passive, receiving, or obedient role, to that of the top or ...
.
Conversely, "static" ropes have minimal stretch and are not designed to arrest free falls. They are used in caving, rappelling, rescue applications, and industries such as window washing.
The UIAA
The International Climbing and Mountaineering Federation, commonly known by its French name Union Internationale des Associations d'Alpinisme (UIAA, lit. ''International Union of Alpine Clubs''), was founded in August 1932 in Chamonix, France ...
, in concert with the CEN, sets climbing-rope standards and oversees testing. Any rope bearing a GUIANA or CE certification tag is suitable for climbing. Climbing ropes cut easily when under load. Keeping them away from sharp rock edges is imperative. Previous falls arrested by a rope, damage to its sheath, and contamination by dirt or solvents all weaken a rope and can render it unsuitable for further sport use.
Rock climbing ropes are designated as suitable for single, double or twin use. A single rope is the most common, and is intended to be used by itself. These range in thickness from roughly . Smaller diameter ropes are lighter, but wear out faster.
Double ropes are thinner than single, usually and under, and are intended for use in pairs. These offer a greater margin of safety against cutting, since it is unlikely that both ropes will be cut, but complicate both belaying
Belaying is a variety of techniques climbers use to create friction within a climbing system, particularly on a climbing rope, so that a falling climber does not fall very far. A climbing partner typically applies tension at the other end of th ...
and leading. Double ropes may be clipped into alternating pieces of protection, allowing each to stay straighter and reduce both individual and total rope drag.
Twin ropes are thin ropes which must be clipped into the same piece of protection, in effect being treated as a single strand. This adds security in situations where a rope may get cut. However new lighter-weight ropes with greater safety have virtually replaced this type of rope.
The butterfly
Butterflies are insects in the macrolepidopteran clade Rhopalocera from the Order (biology), order Lepidoptera, which also includes moths. Adult butterflies have large, often brightly coloured wings, and conspicuous, fluttering flight. The ...
and alpine coils are methods of coiling a rope for carrying.
Gallery of µCT/micro-CT images and animations
2D images / sections
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2D flight-throughs/sections
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Micro-CT 2D top view flight-through of a braided polymer climbing rope Zoom.ogg
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Micro-CT Rope HighRes 2D Rotation 2560x550 750f 25fps.ogv
3D renderings
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3D flight-throughs/sections
Micro-CT Rope HighRes 3D.ogv
Handling
Rope made from hemp
Hemp, or industrial hemp, is a botanical class of ''Cannabis sativa'' cultivars grown specifically for industrial or medicinal use. It can be used to make a wide range of products. Along with bamboo, hemp is among the fastest growing plants o ...
, cotton or nylon is generally stored in a cool dry place for proper storage. To prevent kinking it is usually coiled. To prevent fraying or unravelling, the ends of a rope are bound with twine (whipping
Flagellation (Latin , 'whip'), flogging or whipping is the act of beating the human body with special implements such as whips, rods, switches, the cat o' nine tails, the sjambok, the knout, etc. Typically, flogging has been imposed on ...
), tape, or heat shrink tubing. The ends of plastic fibre ropes are often melted and fused solid; however, the rope and knotting expert Geoffrey Budworth warns against this practice thus:
''Sealing rope ends this way is lazy and dangerous.'' A tugboat operator once sliced the palm of his hand open down to the sinews after the hardened (and obviously ''sharp'') end of a rope that had been heat-sealed pulled through his grasp. There is no substitute for a properly made whipping.
If a load-bearing rope gets a sharp or sudden jolt or the rope shows signs of deteriorating, it is recommended that the rope be replaced immediately and should be discarded or only used for non-load-bearing tasks.
The average rope life-span is 5 years. Serious inspection should be given to line after that point. However, the use to which a rope is put affects frequency of inspection. Rope used in mission-critical
A mission critical factor of a system is any factor (component, equipment, personnel, process, procedure, software, etc.) that is essential to business operation or to an organization. Failure or disruption of mission critical factors will resu ...
applications, such as mooring lines or running rigging
Running rigging is the rigging of a sailing vessel that is used for raising, lowering, shaping and controlling the sails on a sailing vessel—as opposed to the standing rigging, which supports the mast and bowsprit. Running rigging varies bet ...
, should be regularly inspected on a much shorter timescale than this, and rope used in life-critical applications such as mountain climbing should be inspected on a far more frequent basis, up to and including before each use.
Avoid stepping on climbing rope, as this might force tiny pieces of rock through the sheath, which can eventually deteriorate the core of the rope.
Ropes may be flemished into coils on deck for safety, presentation, and tidiness.
Many types of filaments in ropes are weakened by corrosive liquids, solvents, and high temperatures. Such damage is particularly treacherous because it is often invisible to the eye.
Shock loading should be avoided with general use ropes, as it can damage them. All ropes should be used within a safe working load, which is much less than their breaking strength.
A rope under tension – particularly if it has a great deal of elasticity – can be dangerous if parted. Care should be taken around lines under load.
Terminology
"Rope" is a material, and a tool. When it is assigned a specific function it is often referred to as a "line", especially in nautical usage. A line may get a further distinction, for example sail control lines are known as “sheets” (e.g. A jib sheet
In sailing, a sheet is a line (rope, cable or chain) used to control the movable corner(s) ( clews) of a sail.
Terminology
In nautical usage the term "sheet" is applied to a line or chain attached to the lower corners of a sail for the purpos ...
).
A halyard
In sailing, a halyard or halliard is a line (rope) that is used to hoist a ladder, sail, flag or yard. The term ''halyard'' comes from the phrase "to haul yards". Halyards, like most other parts of the running rigging, were classically made of n ...
is a line used to raise and lower a sail, typically with a shackle
A shackle (or shacklebolt), also known as a gyve, is a U-shaped piece of metal secured with a clevis pin or bolt across the opening, or a hinged metal loop secured with a quick-release locking pin mechanism. The term also applies to handcuffs ...
on its sail end. Other maritime examples of “lines” include anchor
An anchor is a device, normally made of metal , used to secure a vessel to the bed of a body of water to prevent the craft from drifting due to wind or current. The word derives from Latin ''ancora'', which itself comes from the Greek ἄγ ...
line, mooring line
A mooring is any permanent structure to which a vessel may be secured. Examples include quays, wharfs, jetties, piers, anchor buoys, and mooring buoys. A ship is secured to a mooring to forestall free movement of the ship on the water. An ''an ...
, fishing line
A fishing line is a flexible, high-tensile cord used in angling to tether and pull in fish, in conjunction with at least one hook. Fishing lines are usually pulled by and stored in a reel, but can also be retrieved by hand, with a fixed attachm ...
, . Common items include clothesline
A clothes line or washing line is any type of rope, cord, or twine that has been stretched between two points (e.g. two sticks), outside or indoors, above the level of the ground. Clothing that has recently been washed is hung along the line t ...
and a chalk line
A chalk line or chalk box is a tool for marking long, straight lines on relatively flat surfaces, much farther than is practical by hand or with a straightedge. They may be used to lay out straight lines between two points, or vertical lines by us ...
.
In some marine uses the term rope is retained, such as man rope, bolt rope, and bell rope.
See also
*
* (splicing tool)
*
*
*
*
*
* Mooring line materials
*
*
*
* (in theatre fly system)
*
*
*
*
*
*
*
*
References
Sources
* Gaitzsch, W. ''Antike Korb- und Seilerwaren'', Schriften des Limesmuseums Aalen Nr. 38, 1986
* Gubser, T. ''Die bäuerliche Seilerei'', G. Krebs AG, Basel, 1965
* Hearle, John W. S. & O'Hear & McKenna, N. H. A. ''Handbook of Fibre Rope Technology'', CRC Press, 2004
* Lane, Frederic Chapin, 1932. ''The Rope Factory and Hemp Trade of Venice in the Fifteenth and Sixteenth Centuries'', Journal of Economic and Business History, Vol. 4 No. 4 Suppl. (August 1932).
* Militzer-Schwenger, L.: ''Handwerkliche Seilherstellung'', Landschaftsverband Westfalen-Lippe, 1992
* Nilson, A. ''Studier i svenskt repslageri'', Stockholm, 1961
* Pierer, H.A. ''Universal-Lexikon'', Altenburg, 1845
* Plymouth Cordage Company, 1931. ''The Story of Rope; The History and the Modern Development of Rope-Making'', Plymouth Cordage Company, North Plymouth, Massachusetts
* Sanctuary, Anthony, 1996.'' Rope, Twine and Net Making'', Shire Publications Ltd., Cromwell House, Princes Risborough, Buckinghamshire.
* Schubert, Pit. ''Sicherheit und Risiko in Fels und Eis'', Munich, 1998
* Smith, Bruce & Padgett, Allen, 1996. ''On Rope. North American Vertical Rope Techniques'', National Speleological Society, Huntsville, Alabama.
* Strunk, P.; Abels, J. ''Das große Abenteuer 2.Teil'', Verlag Karl Wenzel, Marburg, 1986.
* Teeter, Emily, 1987. ''Techniques and Terminology of Rope-Making in Ancient Egypt'', Journal of Egyptian Archaeology, Vol. 73 (1987).
* Tyson, William, no date. ''Rope, a History of the Hard Fibre Cordage Industry in the United Kingdom'', Wheatland Journals, Ltd., London.
Further reading
*
*
External links
Ropewalk: A Cordage Engineer's Journey Through History
History of ropemaking resource and nonprofit documentary film
Watch ''How Do They Braid Rope?''
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Articles containing video clips
Climbing equipment
Mountaineering equipment
Primitive technology