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What is a mooring rope?

The below content from wikipedia.

 
1,What is mooring?
As an ancient word, “mooring” (probably stemming from the Dutch verb meren (to moor) used in English since the end of the 15th century) has accumulated a number of related uses.
When used as noun, the word “mooring” refers to any permanent structure to which a vessel may be secured. Examples of a mooring include a quay, a wharf, a jetty, a pier, an anchor buoy, and a mooring buoy. A ship is secured to a mooring to forestall free movement of the ship on the water. An anchor mooring fixes a vessel's position relative to a point on the bottom of a waterway without connecting the vessel to shore.
When used as a verb, “mooring” refers to attaching a vessel to a mooring by any means.
 
2,What is a rope?
 
A rope is a length of fibres, twisted or braided together to improve strength for pulling and connecting. It has tensile strength but is too flexible to provide compressive strength (i.e. it can be used for pulling, but not pushing). Rope is thicker and stronger than similarly constructed cord, line, string, and twine.
 
3,How many material does a rope have?
Common materials for rope include natural fibres such as manila hemp, hemp, linen, cotton, coir, jute, straw, and sisal.
Synthetic fibres in use for rope-making include polypropylene, nylon, polyesters (e.g. PET, LCP, HDPE, Vectran), polyethylene (e.g. Dyneema and Spectra), Aramids (e.g. Twaron, Technora and Kevlar) and acrylics (e.g. Dralon). Some ropes are constructed of mixtures of several fibres or use co-polymer fibres. Rope can also be made out of metal. Ropes have been constructed of other fibrous materials such as silk, wool, and hair, but such ropes are not generally available. Rayon is a regenerated fibre used to make decorative rope.
 
4,Style of rope construction
 
Laid or twisted rope
 
Laid rope, also called twisted rope, is historically the prevalent form of rope, at least in modern western history. Common twisted rope generally consists of three strands and is normally right-laid, or given a final right-handed twist. The ISO 2 standard uses the uppercase letters S and Z 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 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, and S-twist to be left-handed.
Twisted ropes are built up in three steps. First, fibres are gathered and spun into yarns. 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.[6]
Traditionally, a three strand laid rope is called a plain- or hawser-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.[7]
One property of laid rope is partial untwisting when used. This can cause spinning of suspended loads, or stretching, 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.[citation needed]
Twisted ropes have a preferred direction for coiling. Normal right-laid rope should be coiled with the sun, or clockwise, to prevent kinking. Coiling this way imparts a twist to the rope. Rope of this type must be bound at its ends by some means to prevent untwisting.
 
Braided rope
 
Braided ropes are generally made from nylon, polyester, polypropylene or high performance fibers such as Dyneema, Technora or Vectran. 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 light, is susceptible to friction and has a poor heat resistance.[8][9][10][11]
Braided ropes (and objects like garden hoses, fibre optic or coaxial cables, etc.) that have no lay, or inherent twist, will uncoil better if coiled into figure-8 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 or plain weave. 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 has a core (kern) of long twisted fibres in the center, with a braided outer sheath or mantle of woven 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, the core fibres are usually twisted, and chopped into shorter lengths which makes the rope more stretchy. 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 arborists. 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.
As a hardware supplier, Ijin is able to provide mooring rope in all ports of China. The mooring ropes we can supply contain Polymide /Polyamide /Nylon /PA /Polymide fiber rope, Polypropylene/PP rope, Polythylene /PE rope, Polyethylene terephthalate (PET) rope,etc.We can provide ABS,LR,NKK,CCS,DNV,etc certificate for your vessels.Not only supplying in China, Ijin also can deliver above mooring ropes in your countries.Pls send me e-mail sales@ijinmarine.com for more information.

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