The temperature of the high-temperature bearing is too high, which is an abnormal situation similar to "fever". It is a common and relatively harmful fault of rotating equipment. If the cause is unknown and the handling is improper, it will often lead to getting half the result with twice the effort, reducing the service life of the bearing, increasing the maintenance cost, and even causing the bearing to burn out.

Therefore, quickly identifying the cause of the failure and taking appropriate measures to resolve it is the guarantee for the continuous and safe operation of the equipment.

Excessive bearing temperature —— The culprit is here

There are many reasons for the excessive bearing temperature. The editor has sorted out several common problems for you.

Poor lubrication

Lubrication has a significant impact on the service life, friction, wear, and vibration of bearings. Good lubrication is a necessary condition to ensure the normal operation of bearings. According to statistics, about 40% of bearing failures are related to poor lubrication.

The main functions of lubrication for bearings include:

1) Prevent metal corrosion

2) Prevent foreign matter from entering and play a sealing role

3) Dissipate frictional heat to prevent excessive temperature rise of the bearing.

4) Reduce friction and wear and extend the service life of the bearing.

Common factors causing poor bearing lubrication are:

1) Insufficient lubricating oil (grease)

2) The lubricating oil pipe is blocked by foreign objects, etc.

3) Problems with the quality of the lubricating oil (grease)

4) Failure to add lubricating oil (grease) on time

5) Impurities in the lubricating oil (grease)

Bearing wear

As an important part, bearings are used in various large and small machines. Some machines (such as crushers) operate in a dusty environment. When some fine dust enters the high - speed rotating bearing housing, it deteriorates the lubricating oil or grease in the bearing housing, resulting in poor lubrication and then causing bearing wear.

The crusher operates in a dusty environment.

The bearing continues to rotate under a worn condition. Due to the increase in friction, heat is generated, resulting in an increase in the bearing temperature.

Improper installation

Improper installation is another important cause of bearing overheating. Because whether the bearing is installed correctly has a direct impact on its lifespan and the accuracy of the main machine. Therefore, when installing, it is required that the centerlines of the shaft and the bearing hole must coincide.

If the bearing is installed incorrectly with low accuracy and there is deflection in the bearing, a moment will be generated during rotation, causing the bearing to heat up or wear. In addition, the bearing will also vibrate and the noise will increase, and the temperature rise will also increase.

Inadequate cooling

Inadequate cooling is usually manifested as: blocked pipelines, inappropriate selection of coolers, poor cooling effect, etc.

Cooler

The fouling and blockage of the cooler in the lubrication pipeline will lead to a poor cooling effect, especially during summer production, this problem is particularly common. Some manufacturers even increase or connect coolers in series to enhance the cooling effect.

The situation where the cooler is severely fouled and the bearing temperature is too high with frequent alarms is encountered in many production sites. A more effective solution is to perform acid cleaning and descaling on the cooler before the summer every year.

High vibration

For example, the alignment process of the coupling is poor and does not meet the requirements, the rotor has dynamic and static imbalances, the foundation has poor rigidity, the anchor bolts are loose, and there is rotational stall and surge.

Coupling

During the operation of some rotors, due to corrosion by the medium or wear by solid impurities, or the shaft is bent, an unbalanced centrifugal force will be generated, causing the bearing to heat up, vibrate, and the raceway to be severely worn until it is damaged.

Insufficient and untimely inspection and replacement

If serious fatigue spalling, oxidation and corrosion, wear pits, cracks are found in the bearing, or there is excessive noise that cannot be adjusted, if the replacement is not timely, it will cause the bearing to heat up, make abnormal noises, vibrate, etc., affecting normal production.

In addition, improper bearing disassembly and vibration caused by loose equipment anchor bolts will also cause indentations on the bearing raceway and rolling elements, and cracks in the inner and outer bearing rings. During the operation of the bearing, it should be inspected according to the specified cycle.

Poor bearing quality

The parts of rolling bearings work for a long time under high alternating contact stress in the form of point contact or line contact. The accuracy, lifespan, and reliability of the main machine largely depend on the bearing. Therefore, attention must be paid to inspection during the procurement and acceptance of bearings, and qualified high - quality products from regular manufacturers should be used.

Improper bearing selection

When selecting a bearing, attention should be paid to the bearing's limiting speed and load capacity. It should not be used at a speed exceeding the limit or with an overload, as this will only shorten the bearing's service life and is not worth the loss.