Design For The Spherical Plain Bearing Test Machine And The Thermal Error Compensation

In recent years,although our country has made some remarkable achievements in the research of the spherical plain bearing life evaluation,the research on the bearing life test equipments was still short of systematic and objective.Therefore,it has become an urgent problem that develop the spherical plain bearing life test machine with higher standards and higher precision.Aiming at this problem,this paper designs and manufactures a low-speed and heavy-duty self-lubricating spherical plain bearing test machine,which has wear-amount measurement system and thermal error self-compensation function,based on the test specification of low-speed swing self-lubricating spherical plain bearing.The main research contents are as follows:This paper determined the overall scheme of test machine and developed a spherical plain bearing life test machine according to the principle of spherical plain bearing life test and design requirements,which has swing system and fixture system.The swing angle and frequency of swing system can be adjusted within a certain range.The fixture system is versatile and easy to replace.Moreover,it can carry out life test of spherical plain bearing and self-lubricating liner with different types in virtue of the design of different clamps.Due to the role of environment temperature,the wear-amount measurement system will become thermal deformation on a certain extent,and thus the thermal error is produced,which has a great influence on the testing precision of the tester.In this paper,the heat and heat transfer modes of wear-amount measurement system was analyzed by heat transfer theory firstly.Meanwhile,it established finite element model of the measurement system,carried on temperature field and thermal strain coupling analysis,which has provided reference for thermal error experiment.Secondly,according to the principle of the test machine,this paper designed thermal error test scheme,and collected temperature and thermal error data under three working conditions.Afterwards,it screened for measuring point by using main factors strategy and maximum sensitivity strategy individually,by using MATLAB to calculate the screening results of two kinds of strategy.According to the above results,two kinds of thermal error compensation models were established by using the multiple linear regression theory.After,by comparing the fitting precision and the prediction precision of the two models,the main factors strategys model was established for the final thermal error compensation model.On this account,this paper put forward a feasible scheme of the thermal error compensation for wear-amount measurement system.