Effect of Temperature on The Bearing Performance

Temperature is one of the important factors affecting the bearing performance. In the actual working conditions, the bearings need to face the challenge of high temperature and low temperature environment. Temperature change will not only change the performance of the bearing material, but also affect the characteristics of the lubricant, and then affect the friction, wear and service life of the bearing. This paper will make a detailed analysis of the performance changes of bearing in high temperature and low temperature conditions, discuss the selection of temperature resistant materials, and introduce how to extend the service life of bearing through temperature control management.

ⅠEffect of high temperature environment on bearing

1. High-temperature change of the bearing material

In the high temperature environment, the mechanical properties of bearing materials will change significantly:

The temperature increase will lead to the hardness of bearing material, and then affect its wear resistance and bearing capacity.

Thermal expansion Thermal expansion caused by high temperature can cause the bearing gap to change, which may cause abnormal contact between the rolling body and the roller path.

2. High temperature change of lubricant

Lubricants is easy to deteriorate at high temperature, mainly manifested as:

The viscosity of lubricating oil decreases with the increase of temperature, which affects the formation of oil film.

Oxidative degradation at high temperature will accelerate the oxidation of lubricants, resulting in the lubrication performance decline, the formation of corrosive substances.

3. Common problems and performance

Under high temperature conditions, the bearing may have the following problems:

The friction force increases, leading to the further aggravation of the temperature rise.

Surface wear is accelerated, may appear peeling or cracks.

Noise and vibration are increased, and the bearing life is shortened.

Ⅱ The influence of the low-temperature environment on the bearing

1. Low-temperature change of the bearing material

In a low-temperature environment, the characteristics of the bearing materials will change as follows:

Low temperatures may lead to brittle materials and increase the risk of fracture.

Size shrinkage Low temperature environment will cause the metal parts of bearings to shrink, affecting the assembly clearance and rolling performance.

2. The low temperature change of the lubricant

The influence of low temperature on lubricant is mainly reflected in the following aspects:

lubricating oil or grease increases viscosity at low temperature, hindering the movement of rolling body.

The solidified part of the lubricant may freeze or lose fluidity at extremely low temperatures.

3. Common problems and performance

Under low temperature conditions, the bearing may face the following problems:

It is difficult to start, and the friction force due to poor lubrication increases.

The rolling body cannot move normally, resulting in vibration or noise.

Surface fatigue peeling accelerates.

• Ⅲ Selection of temperature-resistant materials

• In order to maintain the performance of bearings at high or low temperature, suitable temperature-resistant materials should be selected. The following are the common bearing materials and their characteristics:

• 1. High-temperature material

• High temperature bearing steel such as AISI M50, Cronidur 30, etc., with good high temperature resistance.

• Ceramic materials, such as silicon nitride (Si3N4), have extremely high temperature resistance and low thermal expansion coefficient.

• High temperature resistant coating by adding high temperature resistant coating to the rolling body or roll road surface, such as DLC coating, can significantly improve the high temperature resistance.

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2. Low-temperature materials

Low-temperature bearing steel, such as AISI 52100, can adapt to the low-temperature environment after special heat treatment.

Stainless steel materials such as 440C, good corrosion resistance, suitable for low temperature environment.

Polymer materials such as PTFE or PEEK can maintain good lubrication performance at extremely low temperatures.

Ⅳ How to extend the bearing life through temperature control management?

1. Choose the suitable lubricant

The selection of lubricant shall be optimized for the operating temperature:

The high temperature special lubricating oil or grease, such as synthetic lubricant (PAO, esters), is selected under high temperature working conditions, which can remain stable at high temperature.

Low temperature and liquid lubricants, such as silicon-based grease, can provide good lubrication at very low temperature.

2. Temperature monitoring and management

Real-time temperature monitoring By installing temperature sensors to monitor the running temperature of the bearing in real time to ensure that the temperature is always within the safe range.

Heat dissipation system optimization Under high temperature working conditions, add heat dissipation devices, such as air cooling or oil cooling system.

The preheating equipment shall preheat the bearing before starting at low temperature to avoid material damage caused by temperature difference.

3. Optimize the operating conditions

Reduce overload and vibration to reduce the bearing bear overload and vibration, reduce the temperature rise.

Check and maintain the lubricants and clean the seals to ensure that the bearings are in good working condition.

The influence of temperature on bearing performance runs through its whole service cycle, whether in high temperature or low temperature environment, it may bring about problems such as friction increase, lubrication failure or material performance decline. By selecting suitable temperature-resistant materials, optimizing lubricants and temperature control system, the stability and service life of bearings in extreme working conditions can be significantly improved. In practical application, temperature management is the key to ensure the efficient operation of bearings, and also an important guarantee to extend the life of equipment.