全孔反循环气动冲击潜孔锤设计及其冲击碰撞性能研究

Design and Performance of Pneumatic DTH Hammer

设计了一款全孔反循环气动冲击潜孔锤,主要由逆止阀系统、气缸、锤体、芯管、钻头等组成,可在井底形成冲击回转破岩效果,提高硬质地层机械钻速。为使该潜孔锤达到破岩要求,并防止高频冲击导致井底岩屑重复破碎,建立了该潜孔锤的虚拟样机,采用多体动力学和显示动力学仿真方法,对锤体与钻头间的冲击碰撞作用进行了仿真模拟,分析了潜孔锤工作过程中冲击运动组件的碰撞特性及其结构强度,并应用回归分析方法获得了锤体回弹速度与上一循环的冲击末速度关系的计算方程,通过强度分析得出了锤体冲击末速度的最适合范围为5.8～7.2m/s。

A kind of full-hole anti-circulation pneumatic DTH hammer was designed,which was mainly composed of backstop valve,air cylinder,piston,core tube and drill bit and so on.The impact rotary rock breaking effect could be formed on the bottom of the well,and the mechanical drilling rate of hard formation could be improved.In order to meet the requirements of rock-breaking and prevent the repeated fragmentation of debris caused by the high frequency impact collision,a virtual prototype of the DTH hammer was established.The impact collision between the piston and the bit was simulated by multi-body dynamics and Display dynamics to analyze the working characteristics and its strength of the moving components of the DTH hammer.The calculation equation for the relationship between rebound velocity of hammer and final impact velocity of last cycle is obtained by regression analysis method.And the optimum range of 5.8~7.2 m/s for the terminal velocity of the piston is obtained finally.