高速机床轴承温升分析及试验研究

Analysis and Experimental Study on Bearing Temperature Rise of High Speed Machine Tools

高速机床中的轴承摩擦热会引起滚动体变形、“烧轴”等现象,进而导致轴承疲劳寿命降低,影响设备正常运行。以高速角接触球轴承7003C为例,在高速角接触球轴承拟静力学分析的基础上,对轴承进行受力分析。利用局部法建立轴承的摩擦功耗计算模型;在传热学的基础上分析轴承系统传热,建立热传递模型;利用有限元软件建立轴承系统温升模型并进行温升仿真,分析转速、轴向力、润滑油温度对轴承系统温升的影响规律。最后,设计温升试验并与理论仿真进行了对比验证。结果表明,轴承转速增加、轴向力增大均会使轴承系统温升增加,钢球处温升最高,其次是内圈,最后是外圈;润滑油温度对轴承系统温度变化有重要作用。利用高速轴承温升试验机对轴承外圈温度进行试验研究,试验结果与仿真计算结果最大误差率为11.66%,验证了理论计算与模型仿真的合理性,为研究轴承疲劳寿命提供了一定参考。

In high-speed machine tools,the friction heat of bearings will cause the deformation of the roll⁃ing body and the"burning shaft",which will reduce the fatigue life of bearings and affect the normal operation of equipment.Taking high-speed angular contact ball bearing 7003C as an example,based on the quasi-static analysis of high-speed angular contact ball bearings,the force analysis of the bearing is carried out,and the fric⁃tion power calculation model of the bearing is established by using the local method.Based on the heat transfer theory,the heat transfer model of the bearing system is established.The temperature rise model of the bearing system is established and simulated by using the finite element software,and the effects of rotational speed,axial force and lubricating oil temperature on the temperature rise of the bearing system are analyzed.Finally,the tem⁃perature rise test is designed and compared with the theoretical simulation.The results show that the tempera⁃ture rise of the bearing system increases with the increase of the bearing speed and the axial force,and the tem⁃perature rise is the highest at the steel ball,followed by the inner ring,and finally the outer ring.Lubricating oil temperature plays an important role in bearing system temperature changes.The maximum error rate between the test results and the simulation results is 11.66%,which verifies the rationality of the theoretical calculation and the model simulation,and provides some reference value for the study of bearing fatigue life.