Study On The Lubrication Performance Of The Vertical Slide Guide Of The Hydrostatic Pillow

The rapid development of modern manufacturing technology is driven by the rapid development of science and technology.In order to process large parts,it requires higher requirements for the machine accuracy,bearing performance and stiffness.The hydrostatic bearing system has been widely used in large numerical control machine tools because of its strong bearing capacity,minimal friction coefficient and reliable stability.In heavy duty vertical lathes,the advantage of hydrostatic vertical guides is even more pronounced.In actual production,the vertical guide rail is distorted due to the effect of cutting force,meanwhile the deformation of the pillow will have an impact on the oil gap film.However it is difficult to obtain accurate sliding pillow deformation through theoretical calculation.According to the upper content,this paper takes DVT500×50/100Q-NC as the research object.During this process units fluid mechanics,numerical simulation,fluid-structure interaction,tribology,elastic-plastic deformation and using finite volume method to get the oil film pressure field and velocity field in the gap between oil pads and double oil chamber oil pads under different working conditions.Then through Workbench software obtains the deformation rule under various working conditions.At last prediction models are obtained of gap oil film through the deformation of the sliding pillow.The main work that has been done is as follow.Firstly the three-dimensional model and the oil film model are established according to the actual size of the vertical slide guide of the hydrostatic pillow.Based on computational fluid dynamics,tribology theories,the flow equation,bearing capacity equation,stiffness equation are derived.The distribution of pressure and velocity of single and double oil pad under the cutting force 10 KN,20KN,40 KN,60KN,80 KN,100KN and overhanging 155 mm,355mm,555 mm,755mm,955 mm are obtained.This provides data for fluid-structure interaction.Secondly based on elastic-plastic deformation and fluid-structure interaction,it can get the deformation of single and double oil pad under the cutting force 10 KN,20KN,40 KN,60KN,80 KN,100KN and the overhanging 155 mm,355mm,555 mm,755mm,955 mm.Then the prediction model of the oil gap are obtained under various working conditions.The prediction can reveal the influence of various working conditions on the bearing capacity and stiffness of the vertical slide guide of the Hydrostatic pillow.Finally experimental verification on a vertical lathe with DVT500×50/100Q-NC to verify the deformation data.Through force ring and dial indicator obtain the actual deformation of sliding pillow under various working conditions,then comparing them to the numerical simulation to verify the correctness of numerical simulation.