Investigation on Processing Technology of Minimum Quantity Lubrication Nozzle and Its Influence on Atomization Effect

Minimum quantity lubrication （MQL） is a technique that achieves effective lubrication and cooling of the cutting zone by using a minimal amount of cutting fluid. This results in a decrease in the cutting temperature， extending the cutting tool life and improving the surface quality of the workpiece. Optimizing the nozzle settings can enhance the cooling and lubrication performance of MQL， leading to increased processing efficiency and product quality. Nozzles with different shapes are fabricated， and different outlet diameters and wall thicknesses are set. The cutting process takes into account the impact of spindle speed and feed rate. An experimental study is conducted to investigate the atomization cone angle and particle size distribution of different nozzles. The circular nozzle is more conducive to the concentrated injection of an atomized liquid beam. The atomization cone angle is the largest when the nozzle outlet diameter is 1.2 mm. Enlarging the nozzle outlet diameter will increase the diameter of the atomized droplets. The atomization cone angle increases while the droplet diameter decreases with the increase of outlet wall thickness. Properly increasing the outlet wall thickness is beneficial to improving the atomization quality. The droplet diameter increases firstly and then decreases with the increase of spindle speed and feed rate. Increasing the MQL gas supply pressure and reducing the lubricating oil flow rate will improve the atomization quality of the nozzle. Studies on the influence of the MQL nozzle processing technology on the atomization effect can help to enhance the cooling and lubrication performance of the MQL technology， leading to improved processing efficiency and quality.