Heavy duty bearing seat manufacturers introduce how to handle high temperature bearings?

High bearing temperature is a common fault in rotating equipment, which can reduce the service life of bearings and increase maintenance costs. When the temperature rises rapidly and exceeds the standard, it is easy to cause unplanned shutdown or load shedding of the unit, which has a significant impact on economic benefits. Therefore, quickly determining the cause of the fault and taking appropriate measures to solve it is the guarantee for continuous and safe operation of the equipment.

Common causes of excessive bearing temperature.

1. Poor lubrication. If the lubrication is insufficient or excessive, the quality of the lubricating oil does not meet the requirements, deteriorates, or impurities;

2. Insufficient cooling. If the pipe is blocked, the cooler is improperly selected, and the cooling effect is poor;

3. The bearing is abnormal. If the bearing is damaged, the bearing assembly process is poor, and the clearance adjustment of various parts of the bearing box does not meet the requirements;

4. Large vibration. If the alignment process of the coupling is poor and does not meet the requirements, the rotor may experience dynamic and static imbalance, poor foundation stiffness, weak foundation, rotational stall, and surge.

Second, the solution.

When the bearing temperature is high, the following aspects should be addressed:

Improper amount of oil added, too little or too much lubricating grease.

The bearing box should be regularly oiled according to work requirements. After oiling the bearing, the temperature may sometimes be very high, mainly due to excessive oiling. At this point, the phenomenon is that the temperature continues to rise, and after reaching a certain point (typically 10 ℃ to 15 ℃ higher than the normal operating temperature), it will remain unchanged, and then gradually decline.

Bearing oil filling does not meet the requirements or is contaminated.

Improper selection of lubricating grease can not easily form a uniform lubricating film, cannot reduce friction and wear inside the bearing, insufficient lubrication, and the temperature of the bearing increases. When various types of oils are mixed, chemical reactions may occur, leading to deterioration and caking of the oil, reducing the lubrication effect. Oil pollution can also increase the temperature of bearings, causing dust to fall during refueling, causing oil pollution, causing oil pollution in the bearing box, damaging bearing lubrication, and increasing temperature.

Therefore, appropriate grease should be selected, the bearing box and bearings should be cleaned during maintenance, and the refueling pipeline should be inspected and dredged. Mixing of different types of oils is not allowed. When replacing other types of grease, clean the crude oil first. Oil shall be added regularly during operation and maintenance, and the grease shall be properly stored, and moisture-proof and dustproof measures shall be taken.

3 Insufficient cooling.

Check whether the pipeline is blocked, and whether the oil inlet temperature and water return temperature exceed the standard. If the cooler is improperly selected, the cooling effect is poor, and it cannot meet the use requirements, it should be promptly replaced or installed in parallel with a new cooler. The thermal insulation and sealing performance of the central cylinder of the axial flow fan should also be checked.

After confirming that there are no above problems, check whether the coupling is correct.

The calibration of the coupling should comply with process standards. During the calibration of axial flow induced draft fans and hydraulic couplers, the heating expansion of the equipment during operation should also be considered. Due to heating expansion at the impeller side of the induced draft fan, the bearing box rises; When the hydraulic coupler operates, the temperature rises and the bearing rises. Therefore, during calibration, the motor should be higher, and the reserved amount should be determined based on the characteristics of the equipment and temperature parameters during operation.

The inspection of bearings mainly includes the following points.

One is the bearing quality.

When disassembling the bearing box, first check whether the lubricating grease has deteriorated, agglomerated, or impurities, which is an important basis for determining the cause of bearing damage. Second, check whether the bearings are engaged and worn; Check whether the surfaces of the inner and outer rings, rolling bodies, and cages of the bearings are smooth, and whether there are defects such as cracks, rust, peeling, pits, overheating, and discoloration. Check whether the bearing clearance exceeds the standard; Check the shaft sleeve for wear, dents, and peeling. If any, replace the bearing with a new one.

The second is bearing fit.

During bearing installation, the matching of the bearing inner diameter with the shaft and the outer diameter with the housing is very important. When the fit is too loose, relative sliding occurs on the mating surface, known as creep. Once creep occurs, it can damage the worn mating surface, damage the shaft or housing, and the worn powder can invade the interior of the bearing, causing heat, vibration, and damage. When there is excess, the outer diameter of the outer ring will become smaller or the inner diameter of the inner ring will become larger, reducing the internal clearance of the bearing. In order to select a suitable fit, consideration should be given to the nature, magnitude, temperature conditions, and rotation of the inner and outer rings of the bearing.

The third is the adjustment of the fitting clearance of each part of the bearing.

If the bearing clearance is too small, the shear friction loss of grease in the clearance is too large, and the bearing will also generate heat. At the same time, if the clearance is too small, the amount of oil will decrease, and there will be no time to take away the heat generated by friction, and the temperature of the bearing will further increase. However, if the clearance is too large, the dynamic characteristics of the bearings will change, and the operation of the rotor will be unstable. Therefore, it is necessary to select a confirmed bearing clearance based on different equipment and service conditions.

The above is the relevant information shared by heavy-duty bearing seat manufacturers. I hope it can be helpful to you. For more information, please continue to follow us!