机械—射流破岩耦合特性研究

RESEARCH ON THE COUPLING CHARACTERISTIC OF MECHANICS -JETTING ROCK CUTTING

在现代旋转钻井破碎井底岩石中仍是以机械破岩为主,理论与实践证明,射流辅助破岩是提高钻井破岩效率的重要途径,但它们的耦合特性研究极少。文章基于渗流场与应力场的耦合理论分析,进行了机械与射流破岩耦合特性的实验研究。结果表明:射流压力和水楔作用对岩石渗流场、应力场具有重要作用,耦合作用比非耦合作用的破岩效率有较大幅度的提高。在实验条件下,砂岩的耦合作用提高破岩效率40%左右,灰岩的耦合作用提高破岩效率20%左右。

The mechanical- jetting rock cutting method is the main method of rock cutting in contemporary rotary drilling. It is proved by theory and practices that the assisted jetting rock cutting is the important method of improving the drilling rock cutting efficiency, but the research on its coupling is little. Based on the coupling theory analysis of the filtration and stress field, this paper introduces the experimental research on the coupling characteristic of mechanical- jetting rock cutting. The experimental result shows that the function of jetting pressure and water jet play an important role on the filtration and stress field, and the rock cutting efficiency that has been improved in coupling function is further more than non- coupling function. Under the experimental condition, the coupling function in sand is more than 40%, and which in limestone is more than 20%.