Wire rope is complex and not many people take the time to figure out which is best for their project. Think about what kind of project you are doing and then consider how strong and durable you need your wire rope to be. There are an endless amount of wire rope, so choosing the right kind of wire may be difficult.
Here is a guide to finding the right wire rope!
The stiffness of wire rope is crucial when deciding which to use for your project. There are a couple of different ways to measure it, but the most common ways are by axial and bending stiffness.
Bending stiffness speaks for itself – this measures how likely the wire rope is to sag when put under a load. In strands that have multiple layers of wires, the inner layers will support the outer layers while under a load. The wires will then shift and adjust to provide additional support.
Axial stiffness is the measurement of elastic deformation of a wire rope that’s under a load. It is expressed as a ratio of load to deflection. Wires that are tightly wound with many strands won’t experience as much axial gyration as weaker wire ropes.
When trying to decide between different wire ropes, there is one rule, wire ropes that have strands that are made up of a few large wires are more resistant to abrasion and less resistant to fatigue. Wire rope that is made of strands of smaller wires, will suffer from abrasion but hold up against fatigue.
Where you See Wire Rope
Securing cargo to ship decks and securing ships to their moorings are a couple of nautical uses for wire ropes. Lines that go to and from fishing boats, as well as sailboat rigging wires, are also made from wire rope. When choosing wire rope for nautical uses, maritime companies go with wire rope that won’t corrode when used in saltwater.
Next time you’re in the gym, take a look around, you’ll see wire rope everywhere. Wire ropes in gyms are often used to rig weight machines. Most of the machines you use at the gym use wire rope in order to lift the weights. Some companies have developed a strong coated wire rope used for resistance.
Many live theaters have backdrops that move; these backdrops are moved back and forth by wire ropes. The wire rope they use is called galvanized cable. Recreational ziplines are also made out of this type of wire rope because it is sturdy and can handle weather elements.
Vinyl, Nylon and Bare Wire
PVC-coated aircraft cable is able to withstand the damage done from water and the sun. This is wire rope with a vinyl coating that is applied in a PVC sheath. Mines and construction sites prefer bright colored vinyl coatings for safety reasons.
Nylon coated ropes hold up great in high-friction applications that also generate a decent amount of heat. The nylon coating prevents the inner cables from fraying. These coated wire ropes are perfect for push-push control actuators and conveyor belts.
Some wire ropes work perfectly without a coating. When technicians are on a budget they usually request bare wire rope whenever possible.
Galvanized and Stainless Steel
Wire rope is often exposed to harsh conditions. Galvanized steel wire rope has a layer of compressed zinc that will help prevent corrosion. They’re not exactly suited for large bodies of water, but they can withstand some use.
If you are installing wire ropes near saltwater or other forms of moisture, it is safer to go with stainless steel wire rope. stainless steel wire rope stands up better against moisture and seawater.
Strengths, Capacities and Loads
There are two main ways to test the strength of wire rope. Aggregate strength is the collective breaking of the strength of all the wires in a single cable when tested individually. Minimum breaking strength is the smallest load that will pull a wire rope apart.
When suppliers test the capacity of wire ropes they consider the smallest issue to be a failure and will rate the wire rope based on the failing issue. When technicians test the capacity of wire ropes on test sites, they may not consider a small issue to be a failure. However, do not overload your cables because you think it’s safe.
To measure the working load limit, divide the tensile strength by the design factor and the number you get is the maximum working load you can apply without failure.
Silver State Wire Rope is Here to Help!
Silver State Wire Rope and Rigging offers many different types of wire ropes, for all your project needs! You can check out our product catalog to see if we have what you need! If you aren’t seeing the type of wire rope you need, or have questions about which type of wire rope to use, give us a call, and we’d be happy to help!