Rope Selection Guide & Information
Searching for the right rope for your job can be overwhelming. Over the years, manufacturers have produced a variety of ropes for a variety of jobs. Each rope has unique strengths and weaknesses. Particular ropes are well suited for certain jobs and not others. Some ropes have a wide range of capabilities, but there is no “one size fits all” rope. Don’t let the variety scare you. You need the right rope for your job. Here is a guide to some of the most common ropes including their strengths, weaknesses, and which one will be right for your situation.
If you happen to be looking for rope to build a net, we have an excellent guide to netting. The guide includes rope, webbing, and all purpose netting.
Rope Material Properties and Use Cases
Polypropylene ropes are synthetic and possess a variety of unique qualities. Polypropylene rope is particularly suited for use around water and will not rot due to water and is resistant to mildew. This rope is also produced in a variety of colors making it a common choice for barriers at golf courses, parks or even power plants. Because polypropylene floats, it is used to designate swimming lanes in pools. Commercial fishermen commonly utilize this rope, especially in crab and lobster lines. It can also be used for buoy moorings, aquaculture, and net lines.
Pros & Cons
- Positives: dielectric/insulator, floats, water resistant, lightweight, low-cost, color variety.
- Negatives: not UV resistant, stretches (although this could be a positive), susceptible to friction.
- Most Common Uses: Work around electic lines, marine applications, swimming-lane barriers.
Dielectric ability is an important quality of polypropylene rope. Should this rope touch a live electrical wire it will not conduct the electric current. Because polypropylene rope acts as an insulator, electricians and tree workers who work around live electrical wires use polypropylene rope. When using this rope for hauling or hoisting, attention should be given to any abrasions against the rope as it can melt from friction. Polypropylene also lacks stretch memory. When stretched, it will not return to its normal size.
This rope has wide capabilities. If you need a strong rope to be used in or around water, or if you anticipate possible exposure to electricity, then polypropylene rope will be your best choice.
The natural strength and all around utility of manila rope has made it the standard for quality rope. Manila rope consists of all-natural hemp fibers. This creates aesthetic appeal commonly used for decorative fences or other landscaping purposes.
Because of susceptibility to liquid absorption and UV decay, the user should be careful of sustained tension on the rope especially when exposed to the elements. Manila’s absorbing quality makes it the first choice for many physical activities that require direct handling of the rope. For purposes such as tug of war, climbing, obstacle courses, or stage rigging, manila rope absorbs perspiration providing better grip. This rope will not hazardously snap back when broken as other synthetic ropes may. For a quality natural rope that is aesthetically appealing and safe for active handling, manila rope is an excellent choice.
Pros & Cons
- Positives: Visually appealing, snap-resistant, low-cost.
- Negatives: Not UV or water resistant, may harden or rot over long periods of time.
- Most Common Uses: Pulling, decoration, landscaping, rigging.
For superior strength and remarkable stretching capabilities, nylon is the rope of choice. Stronger than both manila and polypropylene, nylon commonly finds itself pulling the heaviest loads and bearing the most weight.
Having superior strength, nylon also maintains a smooth surface and its resistance to abrasion makes it ideal for pulley systems or winches. Also, different fall protection systems or rescue line assemblies are constructed from nylon rope. Within these applications, the strength and elasticity of nylon will be most beneficial.
Pros & Cons
- Positives: Strong, smooth, abrasion resistant, UV resistant.
- Negatives: Absorbs water, weakens in water.
- Most Common Uses: Towing lines, anchor lines, pulleys, winches, tie-downs, fall-protection systems.
While both manila and polypropylene are susceptible to UV damage, nylon rope is resistant to UV, chemical exposure or any other form of rot. Despite the fact that water can weaken the strength of nylon, this effect is so slight that nylon is still commonly used for mooring lines and anchor lines. In fact, nylon rope is a great choice for any tie-down because of its strength, stretch, and sustenance in any environment. The all-around durability of nylon rope makes it useful for any job in any situation.
Few innovations in the past century have been as remarkable and useful as Kevlar, invented in 1965 and produced by DuPont. Among its many uses, Kevlar materials have been used for bullet-proof armor and flame resistant material. Kevlar rope is no less remarkable. Pound for pound, Kevlar rope is far stronger than steel and it will not rust. For this reason, Kevlar rope is used as mooring lines on oil rigs and ships. While nylon rope has certain elastic abilities, Kevlar rope will not stretch at all, making it the best choice when complete stability is needed.
Pros & Cons
- Positives: Strongest rope, freeze resistant, flame resistant, chemical resistant, water resistant, stretch resistant, cut resistant.
- Negatives: Not UV resistant, not immune to damage.
- Most Common Uses: Winch lines, mooring lines, helicopter slings, temperature extreme situations.
Because of its polymeric properties, Kevlar material is susceptible to UV light and should not be permanently exposed to UV rays. Unlike any other rope, Kevlar rope is flame resistant. This rope can resist temperatures 160° C before it begins to weaken, and Kevlar will only strengthen when exposed to subzero temperatures.
One should be aware of any signs of wear on Kevlar rope, as the integrity of the rope can be more seriously compromised than the damage makes it appear. Kevlar’s qualities are best demonstrated in extreme temperature conditions, or any time sheer strength is required.
Styles of Rope
Ropes are not only made with a variety of materials (manila, polypropylene, nylon, Kevlar, etc.), but any given rope can have different styles of braid or twist. Twisted rope appear in the form of a spiral and are created by twisting at least three strands of yarn in alternate directions. This alternation prevents the rope from unwinding, while also making it easy to splice. Because of the speed of their manufacturing, twisted ropes tend to be less expensive.
Braided ropes take on a rounded form and are generally smooth. This feature allows them to be used in high-friction situations like winches and pulleys. During the longer and more expensive process of braiding, several fibers pass above, below and around each other. This relatively recent innovation provides a rope that will not twist, but cannot be spliced.
Several different ways of braiding provide different qualities. Solid braid ropes are a complex braid that may have a filler core. They have high elongation but less strength. Diamond braids rotate fibers over and under one another in opposing directions. A filler is usually placed in the center of this rope giving it moderate strength. Double braided rope can actually be understood as a rope within a rope. One braid is formed over another braid to share the load evenly. Double braided rope is a favorite for boaters, but should be used with caution in manufacturing situations.
Words of Caution When Working with Rope
Because of the wide range of rope use, rope condition, and exposure to the various factors affecting the
rope, it is impossible to make blanket recommendations
as to the correct choice of rope to use. However, we have provided the tensile strength for each diameter and type of rope. These strengths are based on tests of
new and unused rope, with appropriate splices. Proper choice, care, and inspection of the rope are essential for reasonably safe use of the rope. Consult your cordage
vendor for proper use.
Dynamic Loading occurs when rope is subjected to sudden or extreme stress. Figures given as working loads are
void if rope has been subjected to dynamic loading,
high temperatures, long periods of load, extreme stress, improper use, or storage.
The tensile strength charts apply to ropes tested at normal room temperature (70°F). Ropes have lower tensile
strength at higher temperatures. Continued exposure
at elevated temperatures causes permanent damage.
WARNING! MISUSE OF ROPES COULD RESULT IN SERIOUS INJURY.
Rarely can you walk in to your local hardware store and find a full selection of rope types and sizes. Online stores like US Netting not only offer a full selection of all types and diameters of rope, but they will cut to length the rope you need! Matching the right rope to the right job will not only make the job easier, but it will also make the job safer.
Paul Galla, President