粒子冲击钻井破岩仿真模拟研究

粒子冲击钻井是以高速球形硬质钢粒子冲击破岩为主,以高速水力破岩和机械牙齿破岩为辅的钻深井硬地层的一种高效钻井工艺。应用一维应力波基本理论对粒子冲击破岩现象进行了分析,用冲击动力学有限元分析软件IDFEM研究了粒子冲击破岩的规律,得出了适合粒子冲击钻井工艺的如下参数:(1)粒子直径为0.5cm时,其初速度不宜超过200m/s的临界速度;(2)粒子直径在0.3~0.7cm比较合适;(3)粒子入射角度为0~30°比较合适。

Simulation study of rock breaking for particle impact drilling

The particle impact drilling (PID) is a new and powerful method to break hard formation in deep well drilling. It mainly uses high-speed ball-shape hard steel particle to impact and break rock, and uses high-speed hydraulic and mechanical rock breaking as supplement. The phenomenon of particle impact to break rock is analyzed by means of one-dimension stress wave theory and the rule of particle impact is studied with the impact dynamics finite-element software IDFEM. Thus the following parameters suitable for particle impact drilling technology are: (1) The initial speed should not exceed the critical speed of 200 m/s when the particle diameter is 0.5 cm; (2) The suitable particle diameter is 0.3～ 0.7 cm; (3) The suitable particle jet angle is 0～30°.