轴扭复合冲击工具的研制与应用

为提高PDC钻头破岩效率并减小钻具的粘滑振动，研制了一种轴扭复合冲击工具。该工具以自激振荡脉冲射流为能量来源，通过螺旋面结构将轴向冲击力转换为轴扭复合冲击力进行破岩，具有结构简单和轴向、扭向冲击力同步作用的特点。现场应用结果表明:与常规钻具相比，轴扭复合冲击工具的机械钻速提高了95.2%～193.8%，单只钻头进尺增加了46.4%～229.2%；与螺杆钻具相比，轴扭复合冲击工具的机械钻速提高了71.0%；与轴向冲击工具相比，轴扭复合冲击工具的机械钻速提高了66.3%，单只钻头进尺增加了194.0%；与扭向冲击工具相比，轴扭复合冲击工具的机械钻速提高了30.2%～46.8%，单只钻头进尺增加了17.2%～191.8%。研究表明，轴扭复合冲击工具可以提高破岩效率，减小硬地层的粘滑振动，破岩提速效果显著，具有推广应用价值。 

Development and Applications of a Compound Axial and Torsional Impact Drilling Tool

To improve the rock-breaking efficiency of PDC bits and reduce stick-slip vibration, a compound axial and torsional impact tool was developed. This tool, characterized by a simple structure and the synchronous action of axial and torsional impacts, is used to break rocks. To do so, it used a self-excited oscillation pulse jet as its energy source, and converted axial impact force into compound axial and torsional impacts through helical surface structure. Field applications showed that: compared with conventional drilling tools, the ROP of this compound axial and torsional impact tool was increased by 95.2%–193.8%, and the footage of a single bit was increased by 46.4%–229.2%. Compared with PDM drills, the ROP of this tool was increased by 71.0% while compared with axial impact tools, the ROP of this tool was increased by 66.3%, and the footage of a single bit was increased by 194.0%. Compared with torsional impact tools, the ROP of this tool was increased by 30.2%–46.8%, and the footage of a single bit was increased by 17.2%–191.8%. The research results showed that the developed compound axial and torsional impact tool can improve rock-breaking efficiency and reduce the stick-slip vibration in hard formations. With its remarkable rock-breaking effects and ROP improvement, this tool is worth of application and widespread implementation.