Experimental Study On Wear And Performance Degradation Of Linear Rolling Guide Pair Under Heavy Load Conditions

In the actual use of the machine tool,the installation error and long-term unmaintenance will cause the machine tool to be off-loaded,which will lead to the situation that the slider bears heavy load.In addition,some special cases of the guide pair also require to bear heavy load,so it is necessary to study the rolling linear guide pair under heavy load condition,at the same time,it is also necessary to conduct experimental research on the performance degradation of the guide pair under heavy load condition.Therefore,against the background of a major national science and technology project,this paper conducts a performance degradation test study on rolling linear guide pair under heavy load conditions,and analyzes a large number of performance degradation data generated during the test,mainly including the following contents:The double stress test conditions are given.In addition to the requirement of loading load,the operating speed is also required.The wear mechanism and fault mode of rolling linear guide pair are analyzed,and FMECA is given.The performance degradation test method of rolling linear guide under heavy load condition is studied,including running-in test method and performance detection test method.The specific test scheme is given,that is,the performance indexes such as pretension force,vertical static stiffness and accuracy are detected off-line during the running and closing process,and the degradation data of the guide pair performance is obtained.The performance degradation test scheme of rolling linear guide pair under heavy load condition is improved by the data from the bottom test of 4 samples.Based on the established test plan,test setup was conducted for 12 samples,fault data in the test process was recorded,and the test termination fault data of 12 samples were analyzed.Combined with the life data of 4 samples in the bottom test and 16 samples in total,the life and reliability of the samples were evaluated.The shortcomings of the traditional life evaluation method,MLBF,were analyzed.Based on the loading stress,the acceleration factor was introduced into the running speed stress,and the single running length difference of guide pairs of different lengths was considered.The Mean Frequency Between Failure was proposed as a new life reliability evaluation method.According to the wear mechanism of the guide pair,the surface morphology data of the raceway observed during the test was analyzed,and the wear characteristics of the guide pair under heavy load condition were determined.By comparing and analyzing the collected degradation data of pre-drag power,vertical static rigidity and motion accuracy,the degradation law and characteristics of rolling linear guide rail under heavy load condition are obtained,and the degradation rate standard that can be used to predict the failure of guide rail side fatigue is determined from the perspective of degradation rate.The degradation data of noise and hardness are compared and analyzed to determine the characteristics of noise and hardness change under heavy load condition.