You may use the ropes for work or other purposes. but when asked about some of the details about rope, we often do not understand at all or half-baked knowledge. we have to learn in depth, since it often has to be used to get a thorough understanding of rope material and performance. Better and safer ropes make it a good helper in every situation!
The earliest ropes were generally made of natural fibers, with several common natural fibers.
1.Manila hemp, from the stem of a hematoxylin, this plant is a close relative of the banana. In 1864, the British Mountaineering Club selected manila hemp with a diameter of 10 millimetres and a weight of 75 grams per metre for mountaineering rope, which was almost as strong as today’s mountaineering ropes and was stronger when wet.
2.Sisal, mainly used for making cheap rope, is 20% less strong and less supple than manila hemp.
3. Indian, Italian hemp fiber, this natural fiber is strong enough for sailing. However, it had to be tarred to maintain its durability in seawater, and later switched more to manila hemp, but Italian hemp has always been a common rope material for climbing.
4.Other fibers, jute, hibiscus, flax, yellow shell, and cotton can be used to make ropes, but they are not strong enough to be used as climbing ropes and others. It is worth mentioning that coconut fiber is the only natural fiber that can float on water and is resistant to seawater corrosion. There is also a natural rubber that has super stretch (300%), so it is very suitable for use as a shock-absorbing rope, such as bungee cords.
Due to a large number of research and development and application of synthetic fiber, more choices are given to the rope production. A lot of high-quality and cheap synthetic fiber materials replace the traditional natural fiber gradually. At present, the main rope material used are as follows:
5.Nylon (polyamide)
Since the invention of nylon by the Carothers Research Group of DuPont in 1935, it has quickly become the rope of choice for many fields because of its tensile properties and good corrosion resistance when loaded. Now nylon has been developed in many varieties, commonly used for recovery towing,climbing. for nylon 6, it has good toughness, stretch and elasticity, and is therefore very suitable for making kinetic rope. Nylon 66, with a high melting point, has very little stretch, making it suitable as a static rope for cave exploration, rescue and descent.
6.Polyester fiber (polyester)
Developed by British scientists in 1941, chemical name; polyethylene terephthalate. This rope material static extension is very small, and does not lose its strength after water (nylon will lose about 20% of its strength after water), so it is very suitable for marine rope, but also a lot of energy rope used in mountaineering, cave exploration, super anti-UV and anti-wear, the protective jacket of the general ropes is all polyester material, the core part of the rope is nylon material. Its disadvantage is that it is a little heavier, at 1.38 compared to 1.14 for nylon, so the rope made of this material is a little heavy.
7.Polypropylene
Discovered by Italian chemists in 1954, it can be extracted from oil and gas, is inexpensive, chemically stable, has good elongation and high strength. And low specific gravity (0.91), is the lightest rope material, so can float on the water, suitable for making water rescue rope, tug and mooring rope, long time in the water will not absorb water and lose strength. His disadvantages are a low melting point (165 degrees), loss of full strength at 93 degrees, average wear resistance, loss of strength even when used below -29 degrees, and poor UV resistance. So not suitable for use in hot, cold, high friction environments. Not suitable for static ropes.
8.Polyethylene
There are two basic types, high density and low density, and low density polyethylene is not suitable for ropes. Similar in nature to polypropylene, both belong to the class of polypropylene polymers, both have a very low specific gravity (0.95), chemical reaction sluggishness, water resistance, both are similar, due to the smooth texture, tied rope knot easily detached, it has a lower melting point (140) operating temperature of 65 degrees, so not suitable for ordinary rope. But it’s very stable at low temperatures and remains very soft at -73 degrees, so it can be used as a harness for a sled.
9.Aramid (kevlar, tevaron)
In 1964, DuPont successfully developed, in 1975, Kevlar began to be applied to the bulletproof vest, then gradually spread to other products, the weight and diameter of rope is only half of the traditional rope, but its elongation and shock absorption ability is poor, so need to add polyester jacket for protection, to prevent UV rays. wear resistance is poor, great strength loss happen after knot and bending. So it’s not suitable for outdoor rope. The newly developed Tektronix material, now available, has solved this problem, but at three times the cost of a regular rope.
10.UHMWPE fibres (spectral, dyneema)
Dutch scientists produce a colloid that can be stretched and spun by melting polyethylene, a process that produces a high-mode supramolecular polyethylene fibre that is 10 times stronger than steel rope in equal weight. It retains many of the characteristics of polyethylene, with a specific gravity of 0.97. It is also extremely resistant to abrasion and does not degrade in sunlight, but it also inherits a low melting point (147 degrees), poor shock absorption, and a weakness in smooth surfaces, so tied knots are easy to loosen, and are generally used with a triple fisherman’s knot when connected, or stitched on both ends. Despite its drawbacks, its small size, high strength and light weight make it a great rope for climing,towing,lifting,rescue etc. The new generation of high-molded polyethylene 8mm single braided rope is as strong as 18mm nylon rope and half the weight of nylon rope. and it can be applied for industries like marine,lifting,4×4 off road,tug& mooring, arboriculture, safety & access, rescue, military etc.
Other rope material
Other Vickers, Cylindrical, Bates, etc. are not used as outdoor rope materials due to their instability and other weaknesses.
