Causes of excessive bearing temperature

1. Poor lubrication

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

The main effects of lubrication on bearings include:

1) Prevent metal corrosion;

2) Prevent the intrusion of foreign matter and act as a seal;

3) Discharge friction heat to prevent bearing temperature from rising too high;

4) Reduce friction and wear and extend bearing life.

Factors that usually cause poor bearing lubrication include:

1) Insufficient lubricating oil (grease);

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

3) There is a problem with the quality of lubricating oil (grease);

4) Lubricating oil (grease) was not added on time;

5) Lubricating oil (grease) contains impurities.

2. Bearing wear

As an important part, bearings are used in various large and small machinery. However, the working environment of some machinery (such as crushers) is dusty. When some fine dust enters the high-speed bearing seat, the lubricating oil or grease in the bearing seat will deteriorate. , poor lubrication, which in turn causes bearing wear.

When the bearing continues to operate in a worn state, due to the increase in friction, the heat increases, causing the bearing temperature to rise.

3. Improper installation

Improper installation is another important cause of bearing heating. Because the correct installation of the bearing has a direct impact on its life and the accuracy of the main engine, it is required that the center line of the shaft and the bearing hole must coincide during installation.

If the bearing is installed incorrectly, the accuracy is low, and the bearing has deflection, torque will be generated during rotation, causing the bearing to heat up or wear. In addition, the bearings will also vibrate, increase noise, and increase temperature rise.

4. Insufficient cooling

Insufficient cooling usually manifests as: pipeline blockage, improper selection of cooler, poor cooling effect, etc.

The cooler of the lubrication pipeline is scaled and blocked, which will lead to poor cooling effect. This problem is especially common during summer production. Some manufacturers do not hesitate to enlarge or connect coolers in parallel and in series to enhance the cooling effect.

Severe scaling of the cooler and frequent alarms due to high bearing temperature are encountered in many production sites. A more effective solution is to pickle and descale the cooler every year before summer.

5. Large vibration

For example, the coupling alignment process is poor and does not meet the requirements, the rotor has dynamic and static imbalances, poor foundation rigidity, weak foundations, rotational stall and surge.

During operation, some rotors are corroded by media or worn by solid impurities, or the shaft is bent, which will cause unbalanced centrifugal force, causing the bearings to heat up and vibrate, and the raceways to be severely worn until they are destroyed.

6. Failure to check and replace in time

If the bearing is found to have severe fatigue spalling, oxidation rust, wear pits, cracks, or excessive noise that cannot be adjusted, if it is not replaced in time, it will cause the bearing to generate heat, abnormal noise, vibration, etc., thus affecting normal operation. Production.

In addition, vibration caused by improper bearing disassembly and loose equipment anchor bolts will also cause indentations on the bearing raceways and rolling elements, and cracks in the inner and outer races of the bearing. During the operation of the bearing, inspection should be carried out according to the specified period.

7. Poor bearing quality

Rolling bearing parts work under high alternating contact stress for a long time in the form of point contact or line contact. The accuracy, lifespan and reliability of the main engine are largely determined by the bearings. Therefore, you must pay attention to inspections during the purchase and acceptance of bearings and use qualified and high-quality products from regular manufacturers.

8. Improper bearing selection

When selecting a bearing, you should pay attention to the bearing's limit speed and load capacity. It cannot be used at excessive speed or overload, which will only shorten the service life of the bearing and cause more harm than gain.