1、 There may be assembly issues with the bearings, and the following four points should be checked:

1. Check if there are any issues with the lubrication system and if the bearings are effectively lubricated;

2. If there is a sealing ring on the bearing cover, it should be checked whether the sealing ring is too tight. If the sealing ring is too tight, a large amount of heat will be generated when the shaft rotates. At this time, the sealing ring should be replaced;

3. Remove the bearing cover and check if the position of the bearing is tilted (which can be checked with a depth gauge), causing the bearing to become stiff and unable to rotate freely; If this is the case, the bearing should be removed and checked for discoloration. If discoloration occurs, the bearing will be burnt out and must be replaced with a new one;

4. Remove the bearing cover and check the axial clearance and radial clearance of the bearing with a depth gauge to see if the clearance is too small. Otherwise, the bearing will heat up and expand during high-speed operation (this type of heating should not exceed 50 degrees is normal). If there is no clearance after expansion, it will increase frictional resistance, rapidly heat up, and exceed the operating temperature of the bearing. Therefore, it is necessary to ensure the clearance of the bearing to ensure its effective operation; If this is the case, the bearing should be removed and checked for discoloration. If discoloration occurs, the bearing will be burnt out and must be replaced with a new one.

2、 Poor lubrication may cause:

1. The installation error of the oil return hole covered by the bearing causes the lubricating oil of the bearing to circulate inside the bearing cover, and the temperature rises due to the inability to wait for cooling; Check the oil return hole.

2. The large axial force prevents the lubricating oil from timely taking away the bearing temperature; A 0.10mm pad can be added between the inner rings of the two bearings to ensure smoother and more thorough oil lubrication, and to adjust the size of the balance hole.

3. The bearing box is under pressure and the oil temperature is rising; Check if the breathable cap is blocked and if the cooling water is open.