Design And Experimental Research Of Online Mixing Nozzle Based On Minimum Quantity Lubrication Technology

In machining,cutting fluids are often used for lubrication and cooling to improve machining efficiency and reduce tool wear.The cutting fluid contains inorganic salts,fatty acids,etc.,which can provide a good environment for the reproduction of microorganisms,not only causing certain harm to human health and the environment,excessive use will also increase the cost of processing,so it is necessary to study ways that can reduce the amount of cutting fluid used to achieve green cutting processing.Trace lubrication technology has become a promising green lubrication technology due to its wide range of applicable machine tools,low consumption of cutting fluid and high processing quality.The micro cutting fluid online mixing technology is to mix water with micro cutting fluid instantly,and the compressed air is dispersed into a mist and applied to the cutting area to lubricate and cool.This technology can not only reduce the contact between personnel and cutting fluids,but also achieve on-demand dispensing to avoid waste and reduce pollution,so this paper studies the in-line mixing nozzles that can achieve micro-lubrication,and the main research content and results are as follows:1.Design the integrated micro-lubrication nozzle for online mixing and atomization of cutting fluid.The nozzle is divided into two parts: mixing and atomization,the mixing part adopts tangential inlet and spiral plate structure to achieve the online mixing function,and the atomization part adopts the internal mixing air auxiliary atomization,determines the structural parameters and establishes a three-dimensional model,so as to realize the integration of the mixing function of the cutting fluid into the nozzle and disperse into a fog under the action of pneumatic force.The results of the study were to build a three-dimensional model of the nozzle and obtain the actual product by 3D printing.2.Simulate the online mixing effect of the micro-lubrication nozzle and the atomization effect of the nozzle to determine the optimal structure and working parameters.The main influencing factors such as the position,number of spiral plates and the input pressure of the oil were selected,and the orthogonal comparison simulation of the online mixing micro lubrication nozzle was carried out,and the mixing effect and atomization effect were determined as the evaluation indicators in the simulation,and the optimal structure and working parameters were obtained.Through simulation,it is concluded that when the number of spiral plates is 3,18 mm away from the oil inlet,and the input oil pressure is 0.3MPa,the mixing effect is the best;when the input air pressure is 0.3MPa,the droplet diameter is 1.73μm,which can enter the capillary structure of the processing surface to achieve lubrication and cooling effect,and its atomization effect meets the requirements of trace lubrication.3.Build a cutting fluid online mixing nozzle performance test bench,and test and verify the integrated nozzle designed and optimized.Through 3D printing,the optimized nozzle is obtained,and the mixing effect of the nozzle online mixing during the test is based on the concentration of the cutting fluid in the mixture as the evaluation criterion,while the atomization effect of the nozzle is based on the droplet diameter.Through the test verification,it is shown that the integrated nozzle can complete the atomization and mixing function very well,and the test data is consistent with the simulation results,which can meet the requirements of online mixing and trace lubrication.