Prediction Of Operating Environment Quality Of Motorized Spindle Based On Oil-Air Lubrication

As the core components of computer numerical control(CNC)machine tools,High-speed motorized spindle in the participation of advanced cutting to obtain high-quality processing results should also ensure green manufacturing.Oil-air lubrication with good lubrication,low pollution,good sealing,fuel consumption and other advantages has been the promotion of attention and application both at home and abroad.However,oil-air lubrication is not completely pollution-free,Centrifugal force generated by high-speed rotating spindle will make the oil atomized,resulting in environmental pollution,thus endangering human health.In addition,the temperature rise of high-speed motorized spindle affects its accuracy and service life.Therefore,based on the Natural Science Foundation of Liaoning province(2015020122),with spindle temperature and volume fraction of PM2.5 as the goal,this thesis explored the oil-air lubrication system parameters and other factors on the impact of the implementation and optimization,ensuring the machining accuracy and the service life of the spindle and the processing of ambient air quality.Specific research contents are as follows:(1)In this thesis,a 100MD60Y4 spindle was taken as the research object to build the spindle temperature rise test platform of the oil-gas lubrication system.Single factor test method was used to study the temperature rise of the spindle bearing at different speed,air supply pressure,and fuel supply quantity and oil supply interval.The results showed that all factors have different influence on spindle temperature rise,in which the speed has the greatest influence on the spindle temperature rise.(2)The motorized spindle ambient air quality testing platform was set up to analyze the atomization characteristics of lubricating oil under the conditions of oil-air lubrication.This thesis reveals the effects of air supply pressure,fuel supply quantity,and oil supply and spindle speed on the atomization characteristics of lubricating oil.The results showed that all the factors had a significant effect on the atomization of the lubricating oil.Among them,the influence intensity of oil mist PM2.5 cumulative volume distribution percentage was as follows:oil supply interval>air supply pressure>speed>fuel supply quantity;the influence intensity of oil mist PM10 cumulative volume distribution percentage was as follows:air supply pressure>fuel supply quantity>oil supply interval>speed;(3)Using response surface methodology,two-target-parameter mathematical models for a 100MD60Y4 spindle were established using biogeography-based optimization(BBO).The air supply pressure,fuel supply quantity,and oil supply interval are the independent variables and the motorized spindle temperature increase and oil mist PM2.5 cumulative volume distribution percentage were the response variables.BBO was used to design parameters.Under the constraint of ensuring a small temperature increase of the motorized spindle,the influence of the oil mist particle size on environmental quality was considered in order to find a set of optimal lubrication system parameters at a speed of 30000 r · min-1.The nonlinear function was set to the smallest when the air supply pressure was 0.38 MPa,the oil supply was 6.50 mL/h,and the fuel supply interval was 2.98 min.The temperature rise of target function spindle was 13.144 ?,oil mist particle size distribution density was 0.0628.(4)The proposed model can guide the design of operating parameters during operation of the motorized spindle,ensuring that the dynamic characteristics of spindle system while achieving green environmental goals.