Study on the polishing of curved pipe parts by solid liquid two phase abrasive flow

In order to study the effect of abrasive flow on the polishing quality of the elbow parts, 90° elbow is used as the research object. The dynamic pressure and wall shear force of different incident angle flow is numerically simulated by setting the process parameters of elbow polishing, which shows that the properly increase entrance angle can improve the uniformity and reliability of abrasive flow polishing, and then, the numerical simulation analysis of turbulence viscosity and wall shear force for different incident pressures are also simulated. It indicates that the properly enhance inlet pressure is helpful to improve the polishing effect and polishing uniformity. Finally, the abrasive grain polishing test is carried out. After the measurement by Mahr stylus measuring instrument, the surface roughness decreases from 1.968 μm to 0.212 μm, which confirm the effectiveness of abrasive flow processing. The roughness value of the inside at the bend after the polishing of the abrasive grain is 0.274 μm by the measurement of the NT1100 Grating Surface Roughness Meter under the pressure condition of 7 MPa. By comparing the polishing effect of the pipe at different pressure and inflow angle, it is found that increase the pressure and inlet angle can improve the polishing effect of the abrasive flow on the curved pipe, but at the same time the uniformity of the polishing is decreased, in other words, the roughness gap at different positions of the elbow will increase. Therefore, it is exceedingly necessary to make some adjustments when in the actual operation.