Developing Of A Spherical Plain Bearing Tester Under Combined Swinging Condition And Experimental Study

Self-lubricating spherical plain bearings are widely used in aerospace, military and other areas. The working conditions of the bearing in these areas are more complex. Therefore, the bearing loses its function under the action of high oscillating frequency, heavy load and combined swinging. However, there is no unified test equipment and standard to evaluate the tribological properties of self-lubricating spherical plain bearings and this restricts the reliability and upgrade of bearings severely. According to the general situation of spherical plain bearings and test equipments at home and abroad, this paper put forward a programme of spherical plain bearing tester under combined swinging condition, and then the detailed design, computation, installation and debugging of the tester have been completed. After that, the usability of the tester was checked via the friction and wear performance test and at the same time the wear mechanism of the bearing were investigated. The main research works are as follows:The plan of a tester was designed based on the friction and wear behavior, service life and reliability of spherical plain bearings under combined swinging, high frequency and heavy load. The tester not only achieves the combined swinging but also exceeds the limits of oscillating frequency 1Hz. Meanwhile, it resolves the contradiction that the frequency and contact pressure can not raise simultaneously. Assembly drawing of the tester and the part drawing of each part were drawn, and the installation and commissioning works of the power and transmission systems, loading system and measurement system were completed.The error analysis was done for the main parameter of the tester by analog calculating and some performance experiments. It would be found that the errors of the tester were less than those of the published papers at present or equal to this, which could meet the requirements.The influence of different swinging form, oscillating frequency and contact pressure on the friction and wear properties of the self-lubricating plain bearings were analyzed by the experiment of one specific bearing,which verified the rationality of the design of each system and the running steadiness of the tester and the accuracy of measurement for data,which had already reached design goal.The micro analysis of self-lubricating plain bearings friction and wear surface was done with the SEM, EDS and 3-D profile. The wear mechanisms under the different conditions were discussed, which concluded extrusion wear, abrasive wear, adhesive wear and fatigue wear.