连续管钻井双向振动减阻工具设计与试验研究

Design and Experimental Study on Two-way Vibration Drag Reduction Tool for Coiled Tubing Drilling

连续管钻井技术面临的技术难题是摩擦阻力大和钻压传递困难,甚至在注入头施加压力和管壁摩擦阻力的影响下易发生屈曲和卡死现象。为此,在分析现有振动减阻工具优缺点的基础上,研制了涡轮式连续管钻井双向振动减阻工具。该工具利用偏心环旋转引起径向振动和水锤效应使轴向振动实现工具的双向振动,并且可以通过改变偏心质量改变工具的激振力。室内试验结果表明:该工具结构合理,工作稳定可靠,在工作排量下激振力为1 000 N,径向和轴向振动频率分别为11.3和22.6 Hz,压降约为2 MPa。该工具的研制成功可解决连续管钻井中摩阻大和压力传递困难等问题。

The technical problems faced by coiled tubing drilling are high drag and difficult WOB transmission,and it is easy to occur buckle and stuck even under the influence of the pressure applied by the injector head and the frictional resistance of the tubing wall. Based on the analysis of the advantages and disadvantages of the existing vibration drag reduction tools,the turbine-type two-way vibration drag reduction tool for coiled tubing drilling has been developed. The tool uses eccentric ring rotation to cause radial vibration and water hammer effects to enable axial vibration,so as to achieve two-way tool vibration,and change the exciting force of the tool by changing the eccentricity mass. The results of the indoor test show that the tool has reasonable structure,stable and reliable work condition,and has the excitation force of 1 000 N,the radial and axial vibration frequencies of 11. 3 Hz and 22. 6 Hz respectively,and the pressure drop about 2 MPa,under the working displacement. The successful development of the tool can address the issue of large drag force and WOB transmission in coiled tubing drilling.