1. Grease or oil failure or selection error.

Countermeasures: Select the correct grease or oil, check the compatibility of grease or oil.

2、The oil level is too low, the lubricant is lost from the oil seal, and there is insufficient grease in the bearing box.

Countermeasures: The oil level should be slightly lower than the center of the following rolling element, and the grease in the bearing box should be filled with about 1/3 to 1/2 space.

3、The oil level is too high or the bearing box is completely filled with grease, which will lead to high temperature or oil leakage due to full mixing of lubricant.

Countermeasures: grease added to the box to 1/2; if the oil lubrication, the oil level is slightly lower than the center of the rolling body below.

4, bearing clearance is not appropriate, when there is heat flow through the center of the shaft, resulting in excessive expansion of the inner ring.

Countermeasure: Check whether the clearance of the overheated bearing is the original design range, if so, please change to a larger clearance to C3 or C3 to C4.

5、Contact type (friction) oil seal is too dry or spring is too tight.

Countermeasure: Replace the contact type oil seal and lubricate its oil seal surface.

6、Bearing box bore is not round, bearing box twisted deformation, support surface is not flat, box hole inner diameter is too small.

Countermeasures: check the bearing box, bore, adjust the base adjustment piece evenly distributed.

7, rotating oil seal and gland friction, or shaft shoulder friction to the bearing seal cover. Countermeasures; check the running clearance of the rotating oil seal to avoid friction and prevent misalignment.

8, cross-locating or two locating bearings on one shaft, due to excessive axial expansion resulting in insufficient clearance within the bearing.

Countermeasure:

Insert an adjusting piece between the bearing box and the end cap flange to release the axial preload on the bearing.

Move the end caps of either bearing box outward and use the adjusting tabs to obtain clearance between the bearing box and the outer ring, and if possible apply axial spring force on the outer ring to reduce axial flotation of the shaft.

9, the tightening sleeve is too tightly locked.

Countermeasure: Loosen the fixing nut and sleeve, re-lock to ensure that the bearing can rotate freely.

10, with two or more bearings coupled to the center of the shaft, resulting in incorrect linear deviation or angular skew.

Countermeasures; by the adjustment piece to adjust the correct alignment, to ensure that the shaft center coupling in a straight line, especially when the shaft at the same time there are three or more bearings running, more attention.

11, the diameter of the shaft is too large, resulting in excessive expansion of the inner ring, reducing bearing clearance.

Countermeasure:

Grind the shaft diameter to obtain a proper fit between the shaft and the inner ring of the bearing.

Change to a large radial clearance bearing.

12, due to the bearing box hole material is too soft after stressing the aperture becomes larger, resulting in the outer ring in the box hole slippery.

Countermeasures: improve the box material or processing of a steel bushing into the box hole, and then process the bushing bore to the correct size.