轴表面粗糙度以及温度对唇形油封密封性能的影响

Effects of shaft surface roughness and temperature on sealing performance of lip oil seal

为了研究轴表面粗糙度以及油膜温度对唇形油封密封性能的影响,根据油封密封机理,建立了油封唇口与旋转轴之间的流体动力学模型和热学模型以及3种轴表面模型,以泵送率和承载力为密封性能评价指标,研究了油封工作参数以及结构参数对密封性能影响。研究表明:温度的上升将减少油封的泵送率和承载力,在1500 r/min前后承载力呈现先下降后上升的趋势。增大转速能够显著得提升泵送率,但是对承载力的提升十分有限。同等条件下,转速每增加1 m/s,泵送率平均增大1.2 mL/h,承载力平均增大0.19 N。承载力对轴粗糙度比较敏感。轴与唇口的粗糙度比值从0到0.05,承载力平均增加1.53 N。具有平缓波峰波谷的轴表面更能提升承载力。

In order to study the effects of shaft surface roughness and oil temperature on the sealing performance of lip oil seal,according to the sealing mechanism of oil seal,the hydrodynamic model,thermal model between oil seal lip and rotating shaft and three kinds of shaft surface models were established.By taking pumping rate and bearing capacity as the sealing performance evaluation indexes,the effects of oil seal working parameters and structural parameters on sealing performance were studied.The results show that the increase of temperature will reduce the pumping rate and bearing capacity of oil seal,and the bearing capacity decreases first and then increases before and after 1500 r/min.Increasing the rotating speed can significantly improve the pumping rate,but the improvement of bearing capacity is very limited.Under the same conditions,the average pumping rate increases by 1.2 mL/h and the average bearing capacity increases by 0.19 N for every 1 m/s increase in speed.Bearing capacity is sensitive to shaft roughness.The roughness ratio of shaft to lip ranges from 0 to 0.05,and the bearing capacity increases by 1.53 N on average.The shaft surface with gentle peaks and valleys can improve the bearing capacity.