Rubber and polyurethane: choosing for the application

Rubber and polyurethane are not interchangeable in every situation. A material that works well in one component may not be the right choice for another. The intended use, design and operating environment all matter, whether an existing component is being refurbished or a new one is being made.

Why consider polyurethane for an engine mounting or other high-wear part? In our workshop experience, road salt and oil or petrol leaks can be particularly hard on engine mountings and other frequently stressed components. A polyurethane formulation selected for the application may offer better resistance to these exposures than standard rubber. That does not mean every polyurethane part will outlast every rubber part: the result depends on formulation, design, installation and actual working conditions. Any oil or fuel leak should still be repaired, since a material change does not solve the underlying leak.

Start with the job. Consider what the component needs to do: support a load, absorb movement, isolate vibration or operate in a particular environment. Heat, exposure to oils or other substances, and the way the part moves can also affect material suitability. A firmer polyurethane part may also transmit more vibration or noise, so performance and comfort need to be considered together.

The original component is useful evidence. The shape and condition of the original part can help explain how it fits and functions. Let a specialist know whether it is from a vehicle, piece of machinery or another application, and describe how it is used. If it has failed, explain what happened and when you first noticed the problem.

For a new component, share what it needs to do and any drawings, measurements, samples or design requirements you have. This helps begin a conversation about design, material and manufacture for the specific application.

Get advice for the specific part. There is no single material answer for every mounting or rubber product. Discuss the component and application with a specialist to understand whether polyurethane refurbishment or manufacture may be suitable.

Polyparts works with automotive and industrial rubber components, as well as parts used in rail transport, aviation, mining, agriculture and road building. Use the enquiry form to discuss a component or design.