Analysis on adaptability of hydraulic pulse cavitating jet drilling technology

To more effectively promote the application of hydraulic pulse cavitating jet drilling technology （HPCJDT）, many application cases of the HPCJDT have been summarized and analyzed based on the introduce of the mechanism of improving the rate of penetration with the HPCJDT. Results indicate that Hydraulic Pulsating-cavitating Jet Generator has the characteristics of simple structure, convenient application, and strong reliability. It could be used with conventional BHA, mud motor, under balanced drilling string and Power V drilling tool. This tool has been applied from Cenozoic formation to Paleozoic formation, and is suitable for either soft or hard formation. The maximum experimental well depth is up to 6 162 m, and the range of borehole diameter is from 215 mm to 406 mm, using different type PDC drill bit or cone bit. The applying range of drilling parameters is wide without special requirement. Usually, the tool could work over 230 h. The HPCJDT has well adaptability to the present drilling equipments, technological parameters, etc., and the average ROP has been increased by 10.1 to 104.4 percent, it provides a safe and high efficient novel drilling technology for deep drilling.