粒子射流冲击破岩效果影响因素试验研究

The Influencing Factors of the Rock Breaking Effect under Particle Water Jet Impacting

为了更准确地分析粒子射流冲击破岩规律,从而有效指导粒子冲击钻井工艺参数的优选,通过粒子射流冲击破岩正交试验,确定了粒子射流各因素影响破岩效果的重要程度,然后根据单因素粒子射流冲击破岩试验,分析了粒子体积分数、粒子直径、喷射角度等主要因素对破岩效果的影响规律,并优选了粒子冲击参数。试验得出,粒子射流各因素对破岩效果的影响程度由大到小依次为喷射时间、粒子体积分数、粒子直径、喷射角度和喷距,最优粒子体积分数为2.0%,最优粒子直径为1.5mm,最优喷射角度为15°。研究结果表明,岩石破碎孔眼深度与粒子体积分数和粒子直径均成二次函数关系,与喷射角度成四次函数关系;孔眼体积与粒子体积分数、粒子直径和喷射角度均成三次函数关系。该研究结果可为粒子冲击钻井技术的推广应用提供理论支撑。

To highlight the patterns of rock fractures in the dynamic indentation particle water jet more accurately, and to identify optimal process parameters for dynamic indentation operations, orthogonal tests were performed for rock fractures in dynamic indentation involving particle water jet to determine the impact of various factors in particle water jet on rock-breaking performances. Then, considering the impacts of each individual factor, volumetric fractions, diameters, jet angles and other key factors were reviewed to evaluate their impacts on rock-breaking performances. Test results showed the influencing factors of parti- cle water jet on rock-breaking performances could be placed in following order in accordance with the inten sity of their impact, including： jet time, volumetric fraction of particles, diameters, jet angles and dis tances. The optimal particle volumetric fraction was determined to be 2.0~; the optimal particle diameter was determined to be 1.5 ram, and the optimal jet angle was determined to be 15~. Relevant research re- suits showed that the depths of formed holes had a quadratic function relationship with both volumetric factors and particle diameters and a quartic function relationship with jet angles. On the other hand, vol umes of holes had a tertiary function relationship with particle volumetric factors, particle diameters and jet angles. The conclusions after evaluating the results of the study might provide reliable a theoretical foundation for the application and promotion of particle impact drilling techniques.