Optimization Of Oil Sealing Surface Microstructure Of Hydrostatic Guide Based On Neural Network

Hydrostatic guide rail has been widely used in precision machine tools and heavy duty because of its advantages of no wear and good precision maintenance.However,the accuracy of users is affected by the shortage of bearing capacity,static stiffness and so on.In order to further improve the accuracy of the users,it is of great significance to optimize the structure of the oil chamber of the hydrostatic guide rail.In this paper,the influence of oil sealing surface microstructure on the static characteristics of hydrostatic guide rail is analyzed.By analyzing the flow of oil in the oil film of the hydrostatic guide rail with the aid of cfd simulation software,this paper studies the relationship between the structural parameters of the pressurized tank and the pressure of the oil chamber.The purpose of this paper is to improve the static performance of liquid hydrostatic guideway by optimizing the sealing surface structure of liquid hydrostatic guideway.Therefore,the thesis has carried out the following research:(1)Based on the computational fluid dynamics and control equations,the bearing capacity and stiffness of the oil cushion of the circular hydrostatic rotary table arederived.In order to analyze the influence of the pressurized tank on the bearing capacity and stiffness of the oil cushion,cfd was selected to analyze the flow field of the oil cushion with the pressurized groove.According to the structural characteristics of the oil gasket,a structured split-grid method is proposed and applied to the analysis of the flow field of the oil pad in the round platform.By analyzing the influence of geometric parameters of single rectangular pressurized grooves on the pressure of the oil gasket of the round platform,it is proved that the opening of the booster groove on the sealing surface of the hydrostatic guide rail is helpful to improve the bearing capacity and stiffness of the hydrostatic guide rail.At the same time,in the range of geometric parameters,the influence of different cross section pressurized grooves on the pressure of the oil cushion oil chamber of the round platform is compared and analyzed.The results show that the rectangular booster groove is more effective in improving the static characteristics of the hydrostatic guide rail.(2)Because of the advantage of the artificial neural network in nonlinear fitting,the aim of this paper is to improve the pressure of the oil cushion cavity of the round platform.The distance from the single rectangular pressurized tank to the oil chamber,the depth and width of the booster tank are taken as the input.The structure of BP neural network model with output pressure of oil gasket in round platform.In order to obtain an accurate BP neural network model,the BP neural network model was trained by different algorithms based on the model training samples produced by orthogonal experiment and msebu mapemad as the evaluation index.According to the accuracy and efficiency of BP neural network model training,the ga-lm-bp neural network model obtained by BP neural network training with LM algorithm can be initialized by ga algorithm proposed in this paper,and the ga-lm-bp neural network model can be obtained by lm algorithm.The relationship between the geometric parameters of the rectangular pressurized groove on the seal surface of the hydrostatic guide rail and the pressure of the oil chamber is accurately reflected.(3)According to the ga-lm-bp neural network model of rectangular pressurized tank and oil chamber pressure,the geometric parameters of single rectangular booster tank are optimized by ga algorithm.The accuracy of the model is verified by cfd simulation.At the same time,the influence of different number of rectangular pressurized tanks on the pressure of the oil cushion oil chamber of the round platform is simulated and analyzed.The results show that the loading capacity and stiffness of the hydrostatic guide rail are improved in varying degrees due to the change of the microstructure of the sealing surface of the hydrostatic guide rail with different numbers of rectangular booster slots set up on the sealing surface of the hydrostatic guide rail.It is considered that single pressurized tank oil pad and double pressurized tank oil pad are the first choice.(4)In order to verify the feasibility and correctness of the strategy proposed in this paper to improve the static performance of the hydrostatic guide rail,four kinds of hydrostatic pressure rotary test bench with different oil sealing surface microstructures were designed and built according to the simulation results.The experimental results show that the static performance of four liquid hydrostatic rotary test sets with different sealing surface microstructures is comparatively analyzed for a given intake flow rate,the better the static characteristics of the hydrostatic guide rail.But when the flow rate increases to a certain extent,the booster tank loses its due function.Therefore,it is necessary to design the oil surface microstructure of hydrostatic guide rail with good performance.For a given oil sealing microstructure,the higher the flow rate,the better the static performance of the hydrostatic guide rail.