In order to reduce the assembly friction of axle hole parts and improve the assembly positioning accuracy,the gas flow mathematical model of the air floating tool was studied,and the effects of different orifice diameters and gas film thickness on the working stability,bearing capacity and static gas mass flow of the air floating tool were analyzed by simulation.According to the research conclusion,an air floating tool was designed,and the experiment proved that the air floating tool can effectively improve the assembly positioning accuracy of shaft hole parts.The results show that when the orifice diameter is 0.5 mm and the gas film thickness is 20 μm,the air floating tool has good bearing capacity and working stability.