In this paper,the formulas of elasto-hydrodynamic traction coefficients of three Chinese aviation lubricating oils,4109,4106 and 4050,were obtained by a great number of elastohydrodynamic traction tests.The nonlinear ...In this paper,the formulas of elasto-hydrodynamic traction coefficients of three Chinese aviation lubricating oils,4109,4106 and 4050,were obtained by a great number of elastohydrodynamic traction tests.The nonlinear dynamics differential equations of high-speed angular contact ball bearing were built on the basis of dynamic theory of rolling bearings and solved by Gear Stiff（GSTIFF） integer algorithm with variable step.The impact of lubricant traction coefficient on cage＇s dynamic characteristics in high-speed angular contact ball bearing was investigated,and Poincare map was used to analyze the impact of three types of aviation lubricating oils on the dynamic response of cage＇s mass center.And then,the period of dynamic response of cage＇s mass center and the slip ratio of cage were used to assess the stability of cage under various working conditions.The results of this paper provide the theoretical basis for the selection and application of aviation lubricating oil.展开更多
Based on improved test rig with cooling system, the traction experiments for 4109 Chinese aviation lubricant are tested under various simulated working conditions. Both the experimental data thanks to their accuracy a...Based on improved test rig with cooling system, the traction experiments for 4109 Chinese aviation lubricant are tested under various simulated working conditions. Both the experimental data thanks to their accuracy and stability and the better cooling effect of the electric shafts has given the rationality of the experimental rig a strong support. An empirical equation for calculating the traction coefficient of 4109 lubricant, which may be conveniently used for engineering application,is obtained. Furthermore, the rheological properties of the lubricant are investigated.展开更多
To simplify the lubricating system for high-speed bearings and improve its reliability, grease lu-bricated high-speed hybrid ceramic bearings were theoretically and experimentally researched. Bearings with an outer ra...To simplify the lubricating system for high-speed bearings and improve its reliability, grease lu-bricated high-speed hybrid ceramic bearings were theoretically and experimentally researched. Bearings with an outer race of 62 mm and eleven 9.525-mm balls were investigated. Traction coefficient and flash temperature between the bearing races and the balls were calculated and the results show that the traction coefficient of Si3N4 hybrid ceramic bearings is 74% that of the steel AISI 440B ones at 30 000 r/min and 1750 N, and the flash temperature of the hybrid bearings is 49% that of steel ones. Simulating the high-speed bearing rotational conditions, the grease lubricated hybrid ceramic ball bearings were tested and the results show that the power consumption of hybrid ceramic bearing lubricated by grease D at 24 000 r/min and axial load 1750 N is 80% that of steel ones.展开更多
基金financially co-supported by the National Natural Science Foundation of China(No.U1404514)Henan Outstanding Person Foundation(No.144200510020) of ChinaCollaborative Innovation Center of Major Machine Manufacturing in Liaoning,China
文摘In this paper,the formulas of elasto-hydrodynamic traction coefficients of three Chinese aviation lubricating oils,4109,4106 and 4050,were obtained by a great number of elastohydrodynamic traction tests.The nonlinear dynamics differential equations of high-speed angular contact ball bearing were built on the basis of dynamic theory of rolling bearings and solved by Gear Stiff（GSTIFF） integer algorithm with variable step.The impact of lubricant traction coefficient on cage＇s dynamic characteristics in high-speed angular contact ball bearing was investigated,and Poincare map was used to analyze the impact of three types of aviation lubricating oils on the dynamic response of cage＇s mass center.And then,the period of dynamic response of cage＇s mass center and the slip ratio of cage were used to assess the stability of cage under various working conditions.The results of this paper provide the theoretical basis for the selection and application of aviation lubricating oil.
基金This project is supported by National Natural Science Foundation of China !(19990514)
文摘Based on improved test rig with cooling system, the traction experiments for 4109 Chinese aviation lubricant are tested under various simulated working conditions. Both the experimental data thanks to their accuracy and stability and the better cooling effect of the electric shafts has given the rationality of the experimental rig a strong support. An empirical equation for calculating the traction coefficient of 4109 lubricant, which may be conveniently used for engineering application,is obtained. Furthermore, the rheological properties of the lubricant are investigated.
基金Supported by the National Natural Science Foundation of China (No. 50275031) and the Scientific Research Foundation for the Returned Overseas Chinese Scholars the Ministry of Education China (2002)
文摘To simplify the lubricating system for high-speed bearings and improve its reliability, grease lu-bricated high-speed hybrid ceramic bearings were theoretically and experimentally researched. Bearings with an outer race of 62 mm and eleven 9.525-mm balls were investigated. Traction coefficient and flash temperature between the bearing races and the balls were calculated and the results show that the traction coefficient of Si3N4 hybrid ceramic bearings is 74% that of the steel AISI 440B ones at 30 000 r/min and 1750 N, and the flash temperature of the hybrid bearings is 49% that of steel ones. Simulating the high-speed bearing rotational conditions, the grease lubricated hybrid ceramic ball bearings were tested and the results show that the power consumption of hybrid ceramic bearing lubricated by grease D at 24 000 r/min and axial load 1750 N is 80% that of steel ones.
