Types of wire ropes and how to choose

Since there are many types and diameters of wire ropes, this article will help you differentiate and choose the right one according to use.

What is a wire rope?

A wire rope is a rope made of strands of wire strands joined together to form a core rope. The strength varies depending on the number of strands, the structure, and the method of stranding.

The material is often stainless steel or steel, and has the following characteristics

  • High flexibility
  • High tensile strength
  • Excellent impact and abrasion resistance
  • Rust-resistant
  • Highly resistant to heat

Wire ropes are mainly used for lifting, suspending, and securing objects, and utilized in various fields such as fishing, agriculture, forestry, and civil engineering and construction.

Types and selection of wire ropes

There are many types of wire ropes, including ‘wire rope sling’ for lifting loads with cranes, etc., and ’platform wire ropes’ used to secure loads.

Wire rope slings and platform wire ropes with mounts are very similar in appearance. However, due to differences in processing methods, legal regulations, etc., please note that a wire rope with a platform cannot be used for slinging operations.

The appropriate rope diameter depends on the weight of the item to be hung and the method of hanging. It is important to select the right size according to the intended use.

Wire rope sling

玉掛ワイヤーロープ

Platform wire rope

台付ワイヤーロープ

Selecting by rope diameter

Rope diameter is the ’diameter of the circumscribed circle’ of a rope. It is the average of two or more measurements taken at two or more points excluding 1.5m from the rope end.

A wide range of rope diameters are available, from 0.45mm for hanging sign boards and stretching fruit branches to 30mm for slinging work, depending on use.

However, each rope diameter has a specific load capacity, which must be carefully checked before selection.

If you are unsure of the appropriate rope diameter, confirm with the store before purchasing.

Selecting by breaking load

To use a wire rope safely, the amount of load must be within the ’breaking load’ of the rope. The breaking load is the maximum weight or load that a rope cannot withstand which leads to breakage.

For example, a wire rope with a breaking load of 100kg will break if a load of 100kg is applied. Be careful not to confuse it with the term ’load-bearing capacity’, which expresses the range of loads that it can withstood.

The unit of breaking load is sometimes indicated in kN (kilonewtons), which is a unit of force, instead of kg (kilograms). 1kN is approximately 102kg, so always check  the unit of kN by converting it to kg.

In addition to this, ’working load’ may also be indicated. The working load is the load that can be used safely.

For example, a wire rope with a breaking load of 5kN and a working load of 160kg means that the load at which the rope breaks is approximately 510kg and the load at which the rope can be safely used is within the range of 160kg.

Even though wire ropes are sturdy, they naturally deteriorate over time. Therefore, it is very dangerous to use a wire rope with a load just short of the breaking load value. Be sure to select a wire rope with a load capacity within the range of the breaking load and the working load.

Summary

Wire ropes can be used in a variety of fields, and it is very important to select the appropriate type, diameter and specifications of rope for each use to avoid accidents.