The choice of railway vehicle rolling bearing clearance

The choice of railway vehicle rolling bearing clearance - 2019 01 - 02 clearance is an important quality index of rolling bearing, the size of bearing load distribution, vibration, noise and life have a considerable impact. Should consider when the choice of bearing inner ring and the shaft and bearing outer ring and the axle box ( Bearing saddle) Of temperature, load and work caused by the change of the original clearance. JB/T8236 'rolling bearing, double row and four row circular cone roller bearings clearance and adjustment method' in the standard, the rolling bearing radial clearance is divided into 1, 2, 0, 3, 4, 5 groups, clearance values in sequence from small to large. 0 as the standard clearance while apply general working conditions, should be preferred to choose; Group 1, 2, clearance is suitable for the rotating precision is high and strict control of axial displacement occasion; 3, 4, and 5 groups is suitable for the bearing and shaft with interference quantity larger or the occasion of inside and outside the circle temperature difference is bigger. Clearance will reduce the number of roller bearing force, greatly reduce the actual bearing life; Clearance is too small easy to under the condition of temperature influence was jammed. For roller bearing, a small amount of work clearance shall be maintained. Generally speaking, the determination of minimum bearing radial clearance should consider the following main factors: one, with the influence of the amount of interference due to the bearing inner ring and shaft neck with the inner ring outward expansion, caused by radial clearance decreased; Cooperate with outer ring and bearing saddle without the entire week, don't consider the impact on the clearance. Can be calculated by the next type: Dd = D d / ( d+3） ] × D/di type: Dd caused by interference of inner ring raceway diameter expansion amount, mm; D inner ring inside diameter and the axle shaft neck diameter with interference quantity, mm; Inner ring diameter d, mm; Di inner ring diameter, mm. Second, the influence of operating temperature due to the effect of temperature difference on inner and outer radial clearance decreased. Can be calculated by the next type: DT = a [ di（ Ti- T） + Dwe ( Ti + T0) - D（ T0 - T） ] Type: DT, the radial clearance of reduction is caused by temperature difference, mm; A material linear expansion coefficient, 1 / ℃; Ti inner ring temperature, ℃; T0 outer temperature ℃; T the environment temperature, ℃; Dwe roller average diameter, mm; Di inner ring diameter, mm; Outer diameter D, mm. Three, the influence of the inner and outer ring raceway geometry changes in the diameter of the inner and outer ring raceway can also cause a radial clearance reduced, can be calculated by the next type: DV = ( VDep+Vdip) / 2 type: DV caused by inner and outer ring raceway diameter change quantity of radial clearance reduction is, mm; VDep outer ring raceway diameter changes within a single radial plane, mm; Vdep inner ring raceway diameter changes in a single radial plane, mm. （ Railway vehicle resource platform)