The efficiency and safety of the wire rope and the traction sheave is determined by the coefficient of friction between the wire rope and the lining. Sheave wheels, or simply sheaves, minimise such friction and so decrease the wear of lifting and pulling equipment over their service life.

In fact, sheaves are instrumental to keeping safety high and costs low, optimising equipment performance and increasing its longevity.

Factors that can impact on the friction coefficient between the wire rope and the sheave lining include wire structure, load weight, the speed with which the wire moves, lubrication if any, and environmental conditions, such as temperature and moisture.

Corrosion is the enemy of any metal equipment, hence the latter should be appropriately designed (water-proofing, finishing), particularly in a salt water environment.

A multiplicity of designs have been engineered over the years to tackle the different challenges presented by pulling and lifting operations, guaranteeing an optimal coefficient of friction between the sheave and the wire rope.

Suffice it to say that sheaves play a critical role in the processes of industries as diverse as construction, transportation of men and material within mines (vertical and sloping access shaft mining), steel rolling mills and metal processing.

Sheaves carry out a number of functions, from pulling and lifting, to laying underwater pipes and cables.

Even the sturdiest of sheaves require maintenance and careful inspection, as regulated by Australian Standards in AS 3785.7 – Underground mining – Shaft Equipment – Sheaves and AS 2089 – Sheave Blocks for Lifting Purposes.

Just like any other equipment involved in lifting operations, sheaves must be inspected before each use by a competent person. Issues to look out for include wear, fatigue cracks, corrosion and the presence of foreign matter which may impact friction. Periodic greasing may also be required, depending on the application.

Detailed visual checks should be scheduled on a monthly basis. Moreover, Australian Standards lay out the requirements for sheaves testing and certification.

Mandatory proof load testing before service serves to certify that a sheave is fit to stand its standard workload limit with a safety factor of 1.2 or higher.

On-site non-destructive examination techniques, such as magnetic particle testing, should also be regularly implemented to locate fatigue cracks before they become a safety issue.

Reliance Hexham has been involved in work with sheaves for many years and can design, manufacture and overhaul a range of sheave styles and configurations.

Our engineering department has extensive experience in designing, manufacturing and refurbishing of head sheave assemblies for customers in Australia and overseas.

At the same time, our team of qualified tradespeople have over 165 years of industry experience between them, and is well equipped to understand your daily challenges and operational needs.