温度对航空发动机轴承测量的影响

Effect of Temperature on Aero-Engine Bearing Measurement

轴承是航空发动机的核心,在装配过程中需要很高的精度,其测量一般在17~23℃进行。通过在不同的温度下测量轴承,研究温度对轴承内外环和径向游隙测量值的影响。通过在18.8℃和22.8℃两种温度下测量轴承内外环,发现两种温度下轴承内外环测量值变化很小。这种现象可解释为该轴承内外环材料为8Gr4Mo4V,标准件材料为GrWMn,两种材料线性膨胀系数相近,在恒温过程中,轴承和标准件膨胀或收缩相当。在18.8℃和22.8℃两种温度下,轴承的径向游隙测量值相差很小,这是由于轴承内外环和滚动体材料全为8Gr4Mo4V,径向游隙测量值随温度变化量可简化为Δd=dαΔT,线性膨胀系数α(12.5×10-6℃-1)十分小,当温度变化不大时,径向游隙变化很小。

Bearings are the core of aero-engines,which require high precision in the assembly process,and their measurements are generally carried out at 17℃to 23℃.By measuring the bearings at different temperatures,the effect of temperature on the measured values of inner and outer rings and radial clearance of the bearings is investigated.By measuring the inner and outer rings of the bearing at two temperatures,18.8°C and 22.8°C,it was found that the measured values of the inner and outer rings of the bearing changed very little at the two temperatures.This phenomenon can be explained by the fact that the material of the inner and outer rings of the bearing is 8Gr4Mo4V,and the material of the standard part is GrWMn.The linear expansion coefficients of the two materials are similar,so that the bearings and the standard parts expand or contract quite a lot during the constant temperature process.In 18.8℃and 22.8℃two temperatures,the bearing radial clearance measurement value difference is very small,this is due to the bearing inner and outer ring and rolling element material is all 8Gr4Mo4V,radial clearance measurement value with the amount of change in temperature can be simplified as△d=dα△T,linear expansion coefficientα(12.5×10-6(/℃))is very small,when the temperature change is not too big,the radial clearance change is very small.