Ropes

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Rope suppliers offer many different types of rope, including twine, marine rope and elastic cords, all of which are made from either natural or synthetic fibers. Natural ropes, such as manila rope, sisal rope, linen rope, jute rope and cotton rope, are made from plant fibers. Synthetic ropes, such as nylon rope, polyester rope, polypropylene rope, polyethylene rope and Kevlar rope, are stronger and made from more advanced manufacturing processes. The demand for ropes is high throughout the world, especially in the marine, construction, manufacturing, arborist, recreational, hobby, rigging, safety, sporting goods and defense contracting industries.

The two main types of rope construction are twisting and braiding. Twisting involves coiling three or more strands tightly in the same direction, although the yarn within the strands must be twisted in the opposite direction. This counter-twisting produces an all-around balanced rope that will stay together without kinking. Once twisting is complete, each end must be fused to prevent unraveling. Historically, twisting has been the most popular form of rope construction. However, rope braiding has become much more common over time. Braided ropes are popular because they do not spin or untwist while holding a load. Braided rope falls into three categories: hollow diamond, diamond with cores and solid braided rope. Hollow diamond braids do not have a core and are manufactured by weaving strands over and under each other. Diamond braids with cores contain a solid material in the middle, underneath the braid, in order to increase strength. Solid braided rope is tightly woven with a lock-stitch construction that does not unravel when cut. Solid braids and diamond braids with cores cannot be spliced. Splicing is a useful way to create a joint between two ropes or two ends of the same rope by interweaving the strands together. The strongest and most expensive type of rope is called a double braid, in which the rope and the core are braided.

Natural rope materials include manila, sisal, linen, jute and cotton. Manila is a very hard rope that is popular in construction because it is resistant to sunlight, stretches very little and will not melt when exposed to heat like some synthetic ropes. Its fibers are made from abaca leaves, which are very resistant to saltwater. Sisal has less strength than manila but has a very good knot-holding capacity and thus is used in applications such as gardening and bundling, where high strength is not a requirement. Its fibers are taken from the agave plant. Cotton rope is very soft, pliable and easy to handle, but it is not as strong or durable as other natural and synthetic ropes. Synthetic ropes, such as nylon, polyester, polypropylene, polyethylene, Kevlar and various co-polymer blends, tend to be stronger than natural ropes. Nylon is another strong and long-lasting material that rope suppliers and rope distributors use. It has high elasticity compared to other rope materials; it can return to its original shape after being stretched. Nylon rope also has very good shock absorption and is resistant to abrasion, sun and chemical damage. Applications for nylon rope include lifting and towing. Polyester rope, one of the most common ropes used in the boating industry, does not stretch as well, absorb shock or last as long as nylon rope, but it has better resistance to abrasion and chemical damage. Another type, polypropylene rope, is the only synthetic rope variety that floats, and it is used in pools and water sports as well as for light watercraft mooring. However, it has the weakest UV resistance and the lowest melting point of all the ropes.

Rope manufacturers supply a few specific types of rope that are unique and application-specific. Twine is thinner twisted rope usually made from natural fibers such as cotton or linen. Twine is applied in many ways. In kitchens and butcher shops, it is used to tie stuffed poultry together. It can also be used as clothesline or as package tying material. Twine is also used to make sporting goods such as hockey goal nets and basketball nets. Elastic cords contain a multi-strand rubber core and are able to stretch up to 125% of their original length. The core coverings are braided and made of synthetic fibers such as nylon, plastic or natural cotton. Marine rope is rope that is often used on boats, barge crafts, or in docking. It must be made of material that fares well even when exposed to salt and water. Proper storage and care are important in order to maximize the lifespan of a rope and to ensure its continued safety. When properly matched to their applications and carefully maintained, ropes are indispensable utilities.

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Rope Types 

• Braided rope is made of three or more interwoven fibrous strands.
• Cordage is the general term used to refer to any length of fibers, including ropes, cord, lines and strings.
• Cotton rope is soft and pliable, but it does not have the strength of other rope.
  
• Elastic cords, more commonly referred to as "bungee cords," are ropes that have been manufactured to include a multi-strand rubber core, which increases stretching ability, strength and durability.
• Kevlar rope is a cordage variety composed of Kevlar fibers; Kevlar is a synthetic polymer manufactured by DuPont. Kevlar rope has more strength pound-for-pound than steel.
• Manila rope is a specific type of cordage made from hemp fibers and commonly used in a variety of industries due to its strength and resistance to sunlight and saltwater.
• Marine rope is a generalization referring to all cordage, lines and strings used in industrial maritime settings or for nautical purposes.
• Nylon rope is the strongest of all rope and is useful in applications that require high shock absorption. When stretched, it "remembers" and returns to its original shape.
  
• Polyester rope is almost as strong as nylon rope, but it does not stretch as well. Polyester rope is popular in the boating industry.
  
• Polypropylene rope is an inexpensive, light-weight, popular, all-purpose rope, but it is less strong than nylon and polyester rope and will deteriorate when exposed to UV rays.
  
• Rope suppliers sell and manufacture a number of cordage and cord related products sought by the public as well as distributors and retailers.
• Sisal rope is a hard, natural fiber rope that is similar to manila rope, though it is not as strong as manila rope. Common uses include applications in which strength is not a necessity, such as gardening.
• Twine is a strong type of cordage composed of two or more strands of thread or yarn to create a single thin cord that is used in a variety of applications.

Rope Terms

Abrasion Resistance - A rope's ability to hold up under internal and external wearing.

Acceleration Stress - Extra stress placed on rope due to increasing load velocity.

Bend - A knot that joins two ends together from a single or two separate ropes.

Bight - A loop in any part of a rope.

Bitter End - When splicing or tying knots, the end opposite the end that is in use.

Blend - A rope's composition of various synthetic fibers.

Bonding - A liquid coating on rope that prevents absorption of water and provides abrasion resistance.

Capstan - A rotating cylinder used to wind rope.

Cordage - A term that refers to rope, line or string with a small width.

Creep - The gradual increase of a synthetic rope's length over time while under high temperature or load stress.

Elastic Recovery - The degree to which a rope will return to its original shape after being stretched.

Elongation - A rope's deformation in the direction of the load.

End - The end of the rope that is in use.

Fiber - Natural or synthetic material that can be spun into yarn.

Flexibility - A rope's agility and ease of handle under working conditions.

Hand - A rope's feel, determined by touch.

Rigging - The ropes and apparatuses used on sailboats that transfer wind to the ship, moving it forward through the water.

Sliver - A continuous strand of overlapping parallel natural fibers that is ready for twisting.

Splice - The joining of two ropes by interweaving different strands and braids.

Strand - Yarn that is twisted together. A rope is made from strands that are twisted or braided together.

Strength - A measure of a rope's ability to lift a load or do work.

Tensile Strength - The load amount at which a rope will break under tension.

U.V. Resistance - A rope's ability to resist damage from the sun's ultraviolet rays.

Water Repellency - A rope's ability to keep from absorbing water and swelling.

Yarn - Fibers that are twisted together.