Wire rope is a complex mechanical device that has many moving parts all working in tandem to help support and move an object or load. In the lifting and rigging industries, wire rope is attached to a crane or hoist and fitted with swivels, shackles or hooks to attach to a load and move it in a controlled matter. It can also be used to lift and lower elevators, or as a means of support for suspension bridges or towers.

There are three main types, stainless steel, galvanized, and coated wire rope.

1. Stainless Steel Wire Rope

Stainless steel is the standard alloy used in rope and cable. Its resistance to corrosions is much higher than that of galvanized & coated ropes, although there are no differences in strength.

Therefore, it is the preferred material uses in marines and water-based salt industries.

It does not readily react to chemicals from food processing, textiles, and photographic settings.

Its high resistance to corrosion, heat & cold, and pulp & paper chemicals makes stainless steel wire rope a much-needed material for manufacturing precision instruments, automobiles, fishing vessels, petrochemical equipment, and other fields. 

2. Galvanized Wire Rope

Galvanized wire ropes are also steel wire materials that have undergone a galvanizing process to increase their corrosion resistance. The finished wire is immersed in a zinc bath to coat the product completely, i.e., it is galvanized.

Zinc is used in this process because cathode protection increases the life expectancy of the wire.

Although the coating will degrade over time, it is still resistant to rust, corrosion, and other harsh chemicals.

Galvanized wire can be found in the industrial and construction sectors as well as in agricultural and DIY projects.

3. Coated Wire Rope

Stainless steel and galvanized wire can be PVC coated with poly-vinyl-chloride or vinyl.

Coated wire rope comes in various colors such as clear, black, white, or any other color that is required in various industries. PVC coated wire is flexible, weather-resistant, and very cost-effective.

Nylon-coated wire, although not as flexible as PVC, is abrasion-resistant and ideal for businesses in extremely cold regions.

Components of Wire Rope

There are four basic components that make up the design of a finished wire rope:

1. Wires made from metal that form a singular strand

2. Multi-wire strands laid around a core in a helical pattern

3. A fiber or steel core

4. Lubrication

Wire

Wires are the smallest component of wire rope and they make up the individual strands in the rope. Wires can be made from a variety of metal materials including steel, iron, stainless steel, monel, and bronze. The wires can be manufactured in a variety of grades that relate to the strength, resistance to wear, fatigue resistance, corrosion resistance, and curve of the wire rope.

The wires themselves can be coated but are most commonly available in a “bright” or uncoated finish.

Strands

Strands of wire rope consist of two or more wires arranged and twisted in a specific arrangement. The individual strands are then laid in a helical pattern around the core of the rope.

Strands made of larger diameter wires are more resistant to abrasion, while strands made of smaller diameter wires are more flexible.

Core

The core of a wire rope runs through the center of the rope and supports the strands and helps to maintain their relative position under loading and bending stresses. Cores can be made from a number of different materials including natural or synthetic fibers and steel.

Lubrication

Lubrication is applied during the manufacturing process and penetrates all the way to the core. Wire rope lubrication has two primary benefits:

1. Reduces friction as the individual wires and strands move over each other

2. Provides corrosion protection and lubrication in the core, inside wires, and outside surface

Strand Patterns

The number of layers of wires, the number of wires per layer, and the size of the wires per layer all affect the strand pattern type. Wire rope can be constructed using one of the following patterns, or can be constructed using two or more of the patterns below.

· Single Layer – The most common example is a 7 wire strand with a single-wire center and six wires of the same diameter around it.

· Filler Wire – Two layers of uniform-size wire around a center with the inner layer having half the number of wires as the outer layer. Small filler wires, equal to the number in the inner layer, are laid in valleys of the inner wire.

· Seale – Two layers of wires around a center with the same number of wires in each layer. All wires in each layer are the same diameter. The large outer wires rest in the valleys between the smaller inner wires.

· Warrington – Two layers of wires around a center with one diameter of wire in the inner layer, and two diameters of wire alternating large and small in the outer later. The larger outer-layer wires rest in the valleys, and the smaller ones on the crowns of the inner layer.

· Combination – A combination strand is constructed using any combination of two or more of the patterns listed above.

Preformed or Non-Preformed

On a preformed wire rope, the strands and wires are formed during the manufacturing process to the helical shape that they will take in a finished wire rope.

Preformed rope can be advantageous in certain applications where it needs to spool more uniformly on a drum, needs greater flexibility, or requires more fatigue-resistance when bending.