The cause of the bearing temperature is too high
The cause of the bearing temperature is too high
Excessive bearing temperature is a common and harmful fault in rotating equipment. If the cause is unknown and improperly handled, it will often result in twice the effort, reduce the service life of the bearing, increase the maintenance cost, and even cause the bearing to burn out.
Therefore, quickly judging the cause of the failure and taking appropriate measures to solve it is the guarantee for the continuous and safe operation of the equipment.
There are many reasons for the high bearing temperature, and we have sorted out several common problems for everyone.
1. Poor lubrication
Lubrication has an important influence 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 role of lubrication on bearings mainly includes:
1) Prevent metal corrosion
2) Prevent the intrusion of foreign objects and play a sealing role
3) Discharge friction heat to prevent bearing temperature from rising too high
4) Reduce friction and wear and prolong bearing life
The factors that usually cause poor bearing lubrication are:
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) Failure to add lubricating oil (grease) on time
5) Lubricating oil (grease) contains impurities
2. Bearing wear
As an important part, bearings are used in various large and small machinery, and some machinery (such as crushers) have a lot of dust in the working environment. When part of the fine dust enters the bearing seat running at high speed, the lubricating oil or grease in the bearing seat will deteriorate. , poor lubrication, and then the bearing wear. Bearings continue to run in a worn state, and heat increases due to increased friction, resulting in increased bearing temperatures.
3. Improper installation
Improper installation is another important cause of bearing heating. Because the bearing is installed correctly or not, it has a direct impact on its life and the accuracy of the host, so the centerline of the shaft and the bearing hole must be coincident 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 bearing will generate vibration, increase the noise, and increase the temperature rise.
4. Insufficient cooling
Insufficient cooling usually manifests as: pipeline blockage, inappropriate selection of cooler, poor cooling effect, etc. The cooler of the lubrication line is fouled and blocked, which will cause the cooling effect to deteriorate, especially in summer production, this problem is especially common. Individual manufacturers do not hesitate to increase or connect coolers in series to enhance the cooling effect.
The cooler is seriously fouled and the bearing temperature is too high and frequent alarms are encountered in many production sites. A more effective solution is to pickle and descale the cooler before summer every year.
5. Large vibration
For example, the alignment process of the coupling does not meet the requirements, the rotor has dynamic and static imbalance, the foundation rigidity is poor, the ground is weak, the rotational stall and surge. During the operation of some rotors, due to the corrosion of the medium or the wear of solid impurities, or the bending of the shaft, an unbalanced centrifugal force will be generated, which will cause the bearing to heat up and vibrate, and the raceway will be severely worn until it is destroyed.
6. inspection and replacement is not timely
If the bearing is found to be severely fatigued and peeled, oxidized and corroded, worn out pits, cracks, or has excessive noise and cannot be adjusted, if it is not replaced in time, it will cause the bearing to generate heat, abnormal sound, vibration, etc., which will affect the normal operation. Production.
In addition, the vibration caused by improper disassembly of the bearing and loose anchor bolts of the equipment will also cause indentations in the bearing raceways and rolling elements, and cracking of the inner and outer races of the bearing. During the operation of the bearing, the inspection should be carried out according to the specified period.
7. Poor bearing quality
Rolling bearing parts work for a long time under high alternating contact stress in the form of point contact or line contact. The accuracy, life and reliability of the main engine are largely determined by the bearing. Therefore, attention must be paid to the inspection during the purchase and acceptance of the bearing, and qualified and high-quality products from regular manufacturers should be used.
8. Improper bearing selection
When selecting a bearing, attention should be paid to the limit speed and load capacity of the bearing, and it should not be used at excessive speed or overload, which will only shorten the service life of the bearing, which is not worth the loss.
