If your bearings are not designed for high temperatures, operating in high temperature conditions can lead to problems. Extreme heat can have many detrimental effects on bearings if we do not pay attention to heat stabilization, from mills all the way to chains passing through furnaces.

Classic bearings can usually operate at temperatures from 120 to 150 C. Any temperature higher than this can negatively affect efficiency and cause a wide range of problems.

Potential overheating problems

Additional wear

Over time, excess heat can change the microstructure of the steel causing a reduction in the expected life of the bearing. The friction created by the rotation of the bearing creates heat, which can make an already hot environment even more extreme. The resulting heat can cause countless problems and can change the natural wear of the bearing to excessive, destroying your bearing in the process.

Material deformation / expansion

The heat causes the metal to spread, which can create distortion problems. When the metal in the bearing expands, it can reduce the distance between the roller bodies and the sliding track. This change in clearance can cause the bearing to tighten, causing it to fail.

Defective seals

Like bearings, seals also need to be stabilized to survive extreme temperatures. Traditional rubber seals are only designed for certain temperatures, so extreme temperatures can make these seals useless without proper material or stabilization. This can also cause grease from the bearings to release oil that can migrate to other components. Depending on the application, this can be an unwanted side effect, especially if grease leaks onto new parts.

Wrong choice of lubrication

Like seals, special greases are required for high temperature conditions. Standard lubricants are effective up to 150 C, but at higher temperatures the grease will turn into a liquid / oil that will run out and lose all the necessary properties. Without this grease, the bearings are exposed to more friction, which leads to increased wear and shorter life.

What you should consider when choosing high temperature bearings

Lower revolutions per minute (rpm)

As already mentioned, the natural friction caused by rotation creates heat. High temperature bearings combat this by working at lower revolutions per minute than standard bearings. As a result, you should consider rpm for your bearing capabilities to make sure they fit the needs of your operating operations. Some bearing manufacturers offer multiple versions of the same bearing, so you can choose which temperature range best suits your application.

Softer metals

When you modify the heat treatment for the appropriate temperature range, the hardness of the steel is reduced to stabilize the steel. Traditional bearings with resistance up to 150 C have a Rockwellow hardness range of 60 to 64. The hardness rating will be adjusted based on the operating temperatures for high temperature bearings. With lower steel hardness the potential for higher wear is higher at higher speeds, so keep this in mind when choosing a solution for high temperature bearings.

Due to the need for thermally stabilized steels, the invention of bearings with appropriate properties is crucial. The higher the operating temperatures inherently support lower loads, so alternative solutions will be needed. One suggestion is to switch to a material with a higher natural temperature resistance. For example, a 440 stainless steel bearing can be used to meet higher load needs when a high temperature chrome bearing is not sufficient.

Order quantity

Due to their special qualities, high temperature bearings are not always available. Many factories need to produce a certain number of these types of bearings in order to achieve the planned quotas. As a result, there may be minimum quantities associated with factory orders for high temperature bearings. This may not be a problem, depending on how many bearings your app requires, but it’s important to consider when looking for products.

Find the right bearings for your needs

Like many types of bearing failures, overheating can be avoided when choosing the right product for your needs. High-temperature bearings allow your applications to work properly and in extreme conditions, protecting you from spending time and money on expensive maintenance and repairs.