Polyurethane – which is identical to urethane – the names are interchangeable – is often used to make heavy duty wheels needed to perform well under extreme conditions. Those include radical fluctuations in temperature, exposure to harsh elements, and applications that demand that the wheels keep rolling along smoothly over rough terrain beneath tremendously heavy loads.
Tread Thickness on Heavy Duty Wheels
One quality of great importance in terms of the capacity of a polyurethane wheel to carry extremely heavy weight, is the tread design. Most wheels – especially those used on vehicles – have a tread that helps enhance traction when the wheel contacts whatever surface it is rolling across.
When the tread is thicker, the wheel’s ability to handle a heavier load increases dramatically, so most heavy duty urethane wheels – like those found on large tractors or dump trucks – also have relatively deep treads on them. Polyurethane wheels used on something like a wheelbarrow, on the other hand, would have a thin tread because those handle relatively lighter weights.
High Durometer Polyurethane Wheels
Transporting eggs or glass on softer or less rigid wheels makes sense, whereas vehicles that move loads of concrete will need a more rigid wheel that is more resistant to going flat when weighted down by the massive weight it shoulders. Many wheels used on earth moving equipment or in multi-ton military vehicles, for example, need this special capacity. So those who manufacture them rely upon heavy duty engineering that ensures that the urethanes used to make them are extremely high on the durometer scale – more on this later.
The density or hardness of a polyurethane or urethane wheel is measured using a scientific formula that calculates the durometer value of the urethane material. As the durometer value increases, the density or resistance to indentation of the urethane becomes greater. Polyurethane that is low on the durometer scale is bouncier and more elastic, whereas the urethane used in tough heavy duty wheels exhibits high durometer readings.
Customized Heavy Duty Wheels
When wheels are used for unusual industrial applications they will often need to be custom ordered to meet unique specifications. A company that needs a urethane wheel that will be used to lay underwater cable that weighs many tons, has to have a product that is not only capable of carrying a heavy load but can also withstand constant exposure to saltwater.
Those wheels are not available at the local tire store, but there are some specialty companies that can make any kind of poly wheels to exacting custom specifications for use in even the most challenging applications.
To create these products they use teams of scientists, engineers, and design experts. They put their heads together to come up with a precise polyurethane recipe and then build a wheel that will not only perform as expected but will also require less maintenance and have a longer working life. These companies can also refurbish worn out heavy duty wheels to extend their longevity.