Bearing as the main components of the locomotive, traction motor and axle box bearing, in particular, its function plays an important role in transportation safety, locomotive running online, once the fault of the bearings, will cause the whole trains can not run, blocking transportation trunk line, especially the passenger train fails, the negative impact is bigger, once the locomotive bearing failure occurs at the same time, the locomotive repair is very difficult, so as to prevent or reduce the locomotive bearing fault occurs, transportation is very important to the security of locomotive, can in front of the bearing loading would have detected the problems of bearing, ensure that qualified bearing parts get in the car is the focus of this paper.
Bearing damage, often is not a single cause, but under the effect of several aspects comprehensive, under harsh operating conditions to produce vicious circle, cause serious loss bearing, so after the accident, it is often difficult to determine is caused by what, also give us relevant measures to bring certain difficulties, convenient for discussion, first from several aspects to analyze the causes of bearing failure.
Install the impact on the bearing
Assembly when the bearing is not according to the technological requirements, with copper hammer impact bearing cage deformation, caused by traction motor bearings inside and outside the circle of incorrect installation or other reasons and make the axial transverse momentum disappear, cause bearing shaft crushed to death.
Bearing assembly improper cooperate clearance fit, also easy to cause the bearing fault, small clearance is easy to cause the roller and raceway friction heat, with the rising of the temperature, the bearing inner ring, rolling body, cage, outer ring, the temperature of the end cover is not the same, there is a temperature difference between each other, thus expanding quantity is slightly different, also can make further reduce the tolerance clearance, according to the bearing heating. Clearance is too large, the vibration of the roller, roller and race, but also easy to cause the internal load distribution, load bearing roller, the roller load is too large.
Fitting clearance of bearing inner ring and shaft interference quantity discrepancy, it is easy to cause the bearing fault, large amount of interference, it is easy to cause the bearing inner ring cleft, due to excessive tensile stress interference quantity is too small, it is easy to cause the bearing inner ring "relaxation".
Bearing abnormal abrasion
Use after a period of time when the bearing, bearing inner ring, rolling element and cage, outer ring raceway, produce certain defects such as scar, cause poor lubrication of bearing, cause bearing of fever, fever for a long period of time, can lead to:
(1) the bearing lubricating oil dilution. So in the online operation, such as found bearing severe fever, smoke, don't stop, and should keep running to stand ahead, because this moment overheated bearings in melting state, once the parking is unable to walk again after cooling, the main block. Due to these reasons, and further form vicious circle, accelerated overheating and make the bearing damage.
(2) accelerate the fatigue of material, hardness decreased. Serious displacement of bearing inner ring, rolling body round, heating, welding together in the end.
For oil for maintenance of locomotive bearing is very important, especially for bearing the right amount of fuel can guarantee good lubrication bearing,BEST NTN Bearing too much of the lack of oil and gas, are easy to cause bearing failure, and poor lubrication oil and less likely to cause bearing fever, plus much more likely to cause a stir also overheat, so in the maintenance of oil to appropriate, at the same time, bearing lubrication oil clean is also very important, once the fall into the other impurities in the oil and water, will affect the normal clearance and building must be the oil film.
Bearing the use of the time is too long, more than the bearing service life and easy to lead to material fatigue, coupled with strong impact and make the material deformation, stripping, caused the roller and raceway surface grinding, resulting in poor lubrication and vibration.