by 
Fault phenomenon of NTN bearing on transmission: the meshing On Transmission sound of transmission gear and the running sound of NTN bearing are too loud; The transmission makes abnormal noises such as dry grinding and impact.
reason:
Rolling NTN bearing is short of oil (such as NTN bearing in front of the shaft), the steel ball is worn On Transmission and out of round, the raceway has pitting, delamination and scars,
the inner and outer raceways rotate on the shaft or in the housing, or the clearance of NTN bearing is too large. The On Transmission troubleshooting methods are: replenish the engine oil and replace the damaged NTN bearing;
Improper gear processing On Transmission accuracy or heat treatment process cause gear deflection or tooth shape change. The troubleshooting method is: replace the damaged gear;
The backlash is too large or the spline fit clearance is too large. On Transmission The troubleshooting method is: replace the damaged synchronizer hub and shaft;
The repaired tooth surface has not been trimmed for burr, bulge, etc. On Transmission The elimination method is: repair the tooth surface;
The tooth surface is peeled off, delaminated, damaged, worn or even damaged, or the gears are not replaced in pairs during On Transmission replacement and repair. The troubleshooting method is: replace the damaged gear;
The first axis and the second axis are bent and deformed. The elimination method is: replace the deformed shaft;
the center distance of the two holes is changed or the two axes are not parallel. The troubleshooting method is: replace the damaged shell;
After repair, the deflection of the shift fork is incorrect or the single side surfacing is too thick after the shift fork is worn, resulting in inaccurate position of relevant gears. The troubleshooting method is: replace the shift fork;
The fastening nut of the second shaft is loose or the axial positioning of other shafts is inaccurate. The elimination method is: reassemble;
The groove and steel ball of the self-locking device are worn too much, or the self-locking spring is tired and broken, resulting in offside when shifting. The troubleshooting method is: replace the shift fork shaft, steel ball or spring;
Individual gear teeth are broken. The troubleshooting method is: replace the damaged gear;
The gear oil is insufficient, deteriorated, the specification does not meet the requirements, or there are sundries in the oil. The troubleshooting method is: supplement or replace the engine oil that meets the requirements.
1. The load bearing capacity of NTN bearing is much smaller than that of sliding NTN bearing with the same volume. Therefore, the radial dimension of NTN bearing is large.
Therefore, sliding NTN bearings are often used in occasions bearing large load and occasions requiring small radial size and compact structure (such as internal combustion engine crankshaft NTN bearings);
2. NTN bearing has large vibration and noise, especially in the later stage of use. Therefore, NTN bearing is difficult to be competent in the occasions with high precision and no vibration. Generally, the effect of sliding NTN bearing is better
3. NTN bearing is particularly sensitive to foreign matters such as metal chips. Once foreign matters enter into NTN bearing, intermittent large vibration and noise will be generated, which will also cause early damage.
In addition, NTN bearings are also prone to early damage due to metal clip impurities. Even if there is no early damage, the service life of NTN bearings has a certain limit. In short, the service life of NTN bearings is shorter than that of sliding NTN bearings.
However, compared with sliding NTN bearings, NTN bearings have their own advantages and disadvantages and occupy certain application occasions.
Therefore, they can not completely replace each other. However, due to the outstanding advantages of NTN bearings, NTN bearings have developed into the main support type of machinery and are more and more widely used.