Abstract: In order to improve the cutting efficiency of abrasive water jet, the cutting effect of limestone with different process parameters was studied through the developed ultra-high pressure abrasive water jet cutting system. The results show that with the increase of water jet pressure, the cutting depth first increases linearly, and then the growth rate slows down gradually; the optimum abrasive flow parameter is 0.6 kg/min; the optimum initial jet target distance is 5 mm; the cutting depth of abrasive jet decreases with the transverse velocity of nozzle; with the increase of jet cutting angle, the cutting depth presents an M-shaped change trend, and the cutting depth reaches the maximum at 80°. Based on the range analysis of orthogonal experiment, it is clear that the influence weight of process parameters on cutting depth from large to small is water jet pressure, nozzle traverse speed, abrasive flow, nozzle cutting angle and jet target distance. It is concluded that the best combination of cutting parameters is water jet pressure 400 MPa, abrasive flow 0.8 kg/min, nozzle traverse speed 1 mm/s, jet target distance 6 mm and jet cutting angle 80°.
Key words: abrasive jet; cutting depth; coal seam permeability improvement; parameter optimization; range analysis