Since the shaft and the bearing hole size measurement inaccuracies or the roughness of the mating surface does not reach the standard requirements, resulting in too large an interference fit, so that the bearing seat has been greatly extrusion, resulting decrease in the radial gap of the bearing itself, bearing rotation difficulties, fever, the wear increased or stuck, severe cracking installation will cause the bearing inner and outer races. The seat does not rotate often gaps or small with interference, so that does not rotate the seat is likely to produce tiny crawling, leaving the seat with the contact surface of the rolling element replacement seat raceway wear uniform. Also can eliminate the shaft due to thermal elongation leaving the rolling bodies bearing axial jammed. But too large a gap with the seat, will not rotate together with the rolling bodies rotate, to severe wear resulting shaft (or bearing holes) with the inner race (or outer ring), and the emergence of the bearing friction heat, vibration.
Bearing and shaft or bearing bore small interference, the use of the assembly of the indentation method. The easiest way is to use copper rod and hand hammer seat symmetrically beating bearings with interference fit in a certain order, bearing smoothly pressed into. In addition, also available soft metal casing by hand hammer to break into or presses pressed into. Improper operation will seat deformation cracking, or hand hammering on a non-interference fit seat, make indentation or bearing raceways and rolling elements indirectly.
Bearing assembly with shaft diameter surplus larger assembly generally hot charging method. Upcoming bearings placed oil drums filled with oil, machine oil drums external heating with hot water or flame, the process requirements heating the oil temperature control at 80 ℃ ~ 90 ℃, generally will not exceed 100 ° C, will not exceed 120 ° C. Suit in journal bearings heated quickly removed. If the temperature is caused by improper control of the heating temperature is too high, then make the bearings a tempering whose hardness is decreased, the running bearing and easy to wear, spalling, or cracking.
The gap of the bearing is divided into a radial clearance and axial clearance, and its purpose is to ensure that the rolling normal operation and lubrication of the body and compensating the thermal elongation.
For clearance adjustable bearings, because the axial gap and the radial clearance between the proportional relationship, so the installation is as long as the adjusted axial gap can obtain the desired radial clearance, and cut them are generally used in pairs (i.e., mounted on the ends of the shaft or at one end), therefore, only need to adjust the axial gap can be a bearing. Usually shims to adjust the axial clearance, and some can also be used to ring adjustment screw or thrust.
For the bearing clearance can not be adjusted, and because of its radial gap during manufacture, been determined by standard, can not be adjusted, such bearing is mounted on the axis diameter on or after the bearing hole, the actual radial gap known to assemble radial clearance, when assembled to make assembly of the size of the gap in the radial direction just enough to cause the necessary radial clearance in operation, in order to ensure that the bearings are flexible rotation. Such bearings at work, due to the thermal elongation of the shaft when the temperature rises to the inner seat at the relative displacement, so that the radial bearing gap decreases, and even the rolling bodies stuck between the inner and outer races. If the the twin bearings in a bearing (another bearing fixed on the shaft and bearing), and the side cover left between the axial gap, can avoid the above phenomenon.



Other News:
Bearing common cause of failure analysis
Bearing mounted precision Precautions
The bearing assembly determines the quality of the causes of damage
Bearing mounting technical problems
Bearing material should have performance
Regular maintenance of bearing fatigue life
Lubrication of bearing failure first aid
Bearing maintenance steps should pay attention to what matters