Research On The Accuracy Compensation For Ram & Main Spindle Of Floor Type Boring And Milling Machine

Numerical control floor milling and boring machine has good processing adaptability and technological practicality,has been an important universal machine tool,widely used in national defense,metallurgy,energy,transportation,aerospace and other industries.Due to its own structure and inherent laws of physics,the CNC floor-type milling and boring machine is inevitably disturbed and deformed under the Ram,in addition,Ram is a moving part installed in the headstock The position of the center of gravity of the spindle box changes with the sliding ram moving or mounting the functional attachment at the Front End,which causes the spindle box to be unbalanced.The above two points seriously affect the accuracy of the NC floor milling and Boring Machine Therefore,eliminating the deformation of the Ram and overcoming the imbalance caused by the shift of the headstock center of gravity has been the direction of unremitting efforts of machine tool manufacturers.The National Standard(GB/t589.3-2006)requires that the verticality error range of the RAM movement(Z axis)for the spindle box movement(y axis)does not exceed 0.03 mm/500 mm,and the verticality error range of the boring axis to the spindle box movement(y axis)does not exceed 0.03 mm / 1000 mm In order to improve the accuracy of the above,this paper carried out specific research work,the specific content is as follows:1.According to the structure characteristics of NC floor milling and boring machine,the deformation of Ram caused by gravity is analyzed,and the equilibrium state of spindle box caused by ram movement and accessories hanging is analyzed.2.According to the analysis results,the prestress anti-deformation compensation method,the hydraulic tie Rod Compensation Method,the sling cylinder balance compensation method,the double screw position control compensation method and so on are designed to compensate the deformation of the Ram and the balance of the spindle box Raising machine tool accuracy.3.In order to improve the control ability and accuracy level,the corresponding feedback control system is designed according to various compensation methods.4.The example is applied on different type floor milling-boring machine,and the compensation effect of different compensation methods is verified by precision measurement.