What are bearingless rollers?

December 12, 2022

National Plastics & Rubber are the proud manufacturer of bearingless roller systems used across draglines, shovels and other mining equipment. Our innovative system was created in response to the numerous disadvantages presented by traditional roller systems.

Traditional roller systems consist of polyurethane bonded to a solid shaft that rotates on bearings. There are many disadvantages to this system:

1.      Wear out easily

The systems can wear out easily due to rope wear patterns, requiring consistent maintenance. As the polyurethane is bonded to the shaft along the whole length – and the rope generally wears on one section – the whole system needs to be restriped and lagging replaced, although wear has only occurred to one section.

2.      Cost of replacement

The cost of replacing a traditional roller system is unnecessary and unsafe. As the polyurethane is bonded to the shaft, when a segment needs replacing due to wear, the entire roller system must be removed and replaced. This is an expensive task requiring a crane or other lifting equipment to get the system out.

3.      Cost of having spares in stock

To keep machine downtime low, the system needs to be replaced almost immediately after it has been removed. That means numerous spare roller systems, in different sizes, need to be held in stock. There is also often a long turnaround time and lead time if you have stock and need to wait for a replacement roller system.

4.      Bearings can seize up

The bearings can seize up and the roller will then stop turning – causing the rope to wear through.

In response to these concerns, National Plastics & Rubber designed, tested and manufactured our now globally trusted bearingless roller systems. These systems pose many benefits to the mining community – improving safety, machine uptime and site productivity:

1.      Easy replacement

Our bearingless roller segments are manufactured from lightweight polyurethane and can be handled by hand (avg. 8kg) – eliminating the need for a crane or other lifting equipment.

2.      Standardisation

We encourage you to have the same segment across all areas of your machines. This will eliminate the need to store and stock multiple segment sizes and roller systems – a problem encountered when using traditional roller systems. Here, if you are using the same segment, no matter what length shaft or aperture you encounter, you only need to stock one segment – no need for different bearingless roller segments.

3.      Segment rotation

Bearingless roller systems provide you with the ability to rotate out segments that are experiencing wear. The worn segment can be rotated out and used as a spacer – and a new (unworn) segment can be shifted into the wear area. As a result, all of the material can be used, compared to a standard roller where if one section is worn out the whole roller system will need replacing.

4.      Bearing free

Of course one of the main benefits of our bearingless roller systems is that they are bearing free! Therefore eliminating the need for maintenance of the bearings as the segments simply rotate on the shaft. The bearingless roller system comes greased as well to ensure smooth rotation.

At National Plastics & Rubber we strive for continuous improvement, always seeking new innovation opportunities to meet customer inquiries and challenges. We possess state-of-the-art product design facilities to advance our current product range through customisation. Recently we designed a specific roller system to ensure continuous movement and free flowing spin of segment rollers.

National Plastics & Rubber looks forward to the opportunity to supply your site with bearingless roller systems. Give us a call on (07) 3279 3066 or email sales@nationalplastics.net.au for more information or to arrange a shovel or dragline inspection Australia.

Workshop Chock Instructional Video

August 3, 2022

National Plastics & Rubber have expanded our trusted wheel chock range to include a NEW ergonomically designed workshop wheel chock. Complementing our range of quality tested mining products, this chock is purpose designed for the workshop environment.

For more information and to find the answers to the following questions – read our blog. 

  • What is the function of a wheel chock?
  • When should you chock the wheels?
  • Do I need to chock both sides of the wheel?
  • Where should a wheel chock be placed?
Products appearing in this video
Prevent hose failures and hose abrasion. Protect hydraulic hoses from external abrasion using HoseMate

HoseMate – eliminating external abrasion

August 1, 2022

National Plastics & Rubber proudly created HoseMate™ as a purpose designed solution to eliminate external hose abrasion – reducing hydraulic hose failures.

For more information visit hosemate.com.au

Read more on how to protect hydraulic hoses from abrasion with HoseMate™.

Improve site ergonomics with safely maneuverable chock

NEW PRODUCT: Workshop Chock

July 22, 2022

National Plastics & Rubber have expanded our trusted wheel chock range to include a NEW ergonomically designed workshop wheel chock. Complementing our range of quality tested mining products, this chock is purpose designed for the workshop environment.

What is the function of a wheel chock?

The function of a wheel chock is to prevent unwanted movement of vehicles by stopping wheels from being able to roll and move. Chocks can also be referred to as wheel stoppers, stop blocks, and tyre wedge.

For more information and to answer the question of “do wheel chocks actually work” – read our blog on NPR’s range wheel chocks and how they can benefit your family car or heavy duty mining truck fleet. Check out our range of light vehicle chocks and other vehicle, including 4WD wheel chocks.

At NPR we are also proud to offer a range of aviation wheel chocks. Our AerochockTM’s are lightweight aircraft wheel chocks suited for narrow and wide body aircrafts. View the range here.

INTRODUCING THE WORKSHOP WHEEL CHOCK – the easily-manoeuvrable, lightweight and durable solution

Designed in conjunction with Anglo Dawson, the workshop chock was created in response to an incident they experienced where a traditional wheel chock was installed incorrectly, driven over, and as a result became a projectile.

As these incidents were occurring in a workshop environment, we a designed a chock better suited to these conditions. Standard wheel chocks are made to secure a truck on a 10% gradient on the mine site, however these conditions are not present in a workshop. As such, the features present on our standard truck chocks could be removed from the workshop chock.

Featuring a handle and wheels, the workshop chock also eliminates numerous WHS risks – including back strain caused by repeat bending and chocking, as well as removing the need to go under the footprint of the truck.

As the workshop chock is not designed to suit extreme gradients, one size chock will suit all trucks – no need to purchase numerous sizes. One workshop chock will can be used all mining trucks, including CAT dump trucks, Komatsu miming trucks to even the biggest mining truck!

ergonomic workshop wheel chocks


NPR’s workshop wheel chock can be used in any workshop operations requiring the truck to be secured. During maintenance, for example, it is important to ensure large mining trucks do not have the ability to roll and move.


Yes. Both sides of the tyre should be chocked with workshop wheel chocks. This will ensure the truck cannot roll either way.


Using the handles and wheels, manoeuvre the chock into position, this should be flush against the tyre with the handle against the sidewall. Watch our instructional video for more information.

National Plastics & Rubber’s workshop wheel chock for trucks is the ultimate wheel stopper for the workshop environment – preventing projectile chocks and ergonomically designed – a winner!

For more information or a quote get in contact with us – click here.

To suit mining equipment with a smaller tyre width (such as Graders) check out our Size 4 Workshop Wheel Chock. 

Small safety chocks for graders, small trucks & light vehicles     small lightweight chocks for the workshop

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