Sealing Characteristics Analysis And Optimization Of Supporting Wheels Of Tracked Paddy Tractors

With the development of agricultural modernization,the sealing problem of the supporting wheels of tracked paddy tractors has attracted wide attention.Failure of bearing wheel seal system not only increases the maintenance cost of users,but also affects the golden period of crop sowing and harvesting,which can not meet the needs of mechanized development of paddy field operations.Aiming at the difficult sealing problems such as seepage and oil leakage of the supporting wheels of a tracked paddy tractor,this paper takes the supporting wheels of a certain type of tracked paddy tractor as the research object.Firstly,a three-dimensional model of the bearing wheel seal system is established by analyzing the structure of the traveling system of the tracked tractor,and the theoretical analysis of the sealing system and the fundamental causes of the seal failure are explored.Then,the simulation model of the dynamic and static seal pair of the supporting wheel of the tracked paddy tractor is established by using the finite element analysis software Abaqus,and the dynamic and static seal is carried out by using the pressure image analysis system.The contact stress between the pairs was tested to verify the accuracy of the simulation model.At the same time,the static simulation analysis of the rotating shaft and the mechanical end face of the seal pair and the liquid film fluid simulation analysis in the moving ring-liquid film-static ring were carried out,and the influence rule of the important parameters of the seal pair on the sealing performance was analyzed.Secondly,the structure of the dynamic and static seal pair was optimized and the seal pair samples were made.Finally,a test-bed for testing the sealing performance of dynamic and static sealing pairs was built,and the comparison test of sealing performance before and after optimization was carried out.The results show that when the air side lip angle of the rotating shaft lip of the supporting wheel dynamic and static seal pair is 25 degrees,the oil side lip angle is 30 degrees,the interference is 0.5 mm,and the surface friction coefficient is 0.5,the sealing effect of the supporting wheel dynamic and static seal pair is the best when the pre-tightening pressure of the end face of the dynamic and static ring is 40 N and the inclination angle is 6 degrees.When the difference between the inner and outer diameters of the static ring is constant and the inner diameter is 35 mm,the opening force and leakage of the liquid film can be greatly reduced.The service life of the optimized seal pair is more than twice as long as that of the optimized seal pair.Through the simulation analysis and optimization improvement of the bearing wheel seal pair,as well as the comparison test of the dynamic and static sealing pairs before and after the optimization improvement,the effectiveness of the optimization effect is verified,which provides theoretical guidance for the improvement and development of the bearing wheel seal performance of tracked paddy tractor.