Design Of Toggle Lever Hydrostatic Bearing In NTR Upsetting Press

Upsetting press is a kind of horizontal crank press. In order to adapt to bad workingcondition, bearing need high performance. In the work process, the change of the togglebearings’ load is huge, the coupling deformation is large, and also the capacity of workspace is limited seriously. Now hydrostatic bearing of low speed and heavy loading mainlyadopts constant flow in oil supply, which is difficult to guarantee the safe operation of thebearing. In order to satisfy the performance requirements of toggle bearing, designoptimization of toggle hydrostatic bearing should be performed.In this thesis, according to the working characteristics of low speed, heavy load andlarge range of load change, performance analysis and structure optimization design ofbearing is carried out, and to adapt to changes in load and adjust oil film thickness thevariable flow of oil is proposed. The main content includes the following three parts:(1) According to the requirements for functional and performance parameters ofhydrostatic bearing, the bearing structure optimization design scheme was determined,The oil film equations and the boundary conditions were established, static characteristicwas computed, which laid a solid foundation for the subsequent analysis and optimization.(2) The thesis analyzed how the bearing performances change under the structuralparameters of oil cavity, wrap angle and radial clearance by theory analytical method.Bearing oil film fluid simulation and the spindle elastohydrodynamic coupling analysiswas studied by using ANSYS FLUENT software, and the oil film pressure fielddistributions and elastohydrodynamic coupling deformation results were obtain, whichverified the rationality of the structure optimization design of the bearing, and the bearingstructure parameters was determinated.(3) The constraint of allowable oil film thickness and the largest allowable oil filmpressure which conform to the requirements was set; adapting to changes in load andadjusting oil film thickness was designed as the optimization objective; optimization studyof variable oil flow was completed through the method of oil film thickness equivalentsubstitution. Oil flow of each cavity under full load was designed. Bearing oil film thickness after unloading was calculated. It proves that the constant flow oil supply can’tsatisfy the bearing requirements of bearing in the whole process. The design of the bearinglubricating oil in variable flow scheme was completed, and the feasibility of this schemewas analyzed, which verifies the validity of the variable flow oil supply. Finally, the thesisgives the variable flow oil supply curve in an upsetting cycle changes over time.