High bearing temperature is a common and harmful failure of rotating equipment, which will reduce the service life of bearings and increase maintenance costs. When the temperature rises quickly and the temperature exceeds the standard, it may easily lead to unplanned shutdown or reduced load operation of the unit. The economic benefits have a great impact. Therefore, to quickly determine the cause of the failure and take appropriate measures to solve it is the guarantee of continuous operation of the equipment.
Common causes of excessive bearing temperature
1) Poor lubrication, such as insufficient lubrication or excessive lubrication, the quality of the lubricating oil does not meet the requirements, deteriorates or has debris;
2) Insufficient cooling, such as blocked pipes, inappropriate selection of cooler, poor cooling effect;
3) Abnormal bearing, such as bearing damage, poor bearing assembly technology, gap adjustment of each part of the bearing box does not meet the requirements;
4) Vibration is large. For example, if the process of the coupling is not correct, the rotor has dynamic and static imbalances, the foundation rigidity is poor, the ground is weak, the rotation stall and surge are present.
When the bearing temperature is high, the following problems should be solved first:
1) Improper refueling amount, too little or too much grease
The bearing box should be refueled regularly in accordance with the requirements of the job. After the bearing is refueled, sometimes the temperature is high, mainly due to excessive refueling. At this time, the phenomenon is that the temperature continues to rise continuously. After reaching a certain point (generally about 10 ° C to 15 ° C higher than the normal operating temperature), it will remain unchanged and then gradually decrease.
2) The grease added to the bearings does not meet the requirements or is contaminated
The selection of lubricating grease is not suitable, it is not easy to form a uniform lubricating oil film, it is not possible to reduce the internal friction and wear of the bearing, the lubrication is insufficient, and the bearing temperature rises. When different types of grease are mixed, a chemical reaction may occur, causing the grease to deteriorate and agglomerate, reducing the lubrication effect. Contamination of grease will also increase the temperature of the bearing. Dust will fall into the process of adding grease, which will cause grease pollution, resulting in deterioration of the grease inside the bearing housing, which will damage bearing lubrication and increase the temperature.