Author: LIU Yong DAI Shuo WEI Jianping GUO Xinhui YUAN Yongwang | Time: 2023-05-10 | Counts: |
LIU Y, DAI S, WEI J P,et al.Study on motion equations and technical parameters of borehole restoration for self-propelling drill[J].Journal of Henan Polytechnic University(Natural Science) ,2023,42(3):1-9.
doi:10.16186/j.cnki.1673-9787.2021110075
Received:2021/11/18
Revised:2022/02/28
Published:2023/05/25
Study on motion equations and technical parameters of borehole restoration for self-propelling drill
LIU Yong1,2,3, DAI Shuo1,2,3, WEI Jianping1,2,3, GUO Xinhui1,2,3, YUAN Yongwang1,2,3
1.State Key Laboratory Cultivation Base for Gas Geology and Gas Control,Henan Polytechnic University,Jiaozuo 454000,Henan,China;2.State Collaborative Innovation Center of Coal Work Safety and Clean-efficiency Utilization,Henan Polytechnic University,Jiaozuo 454000,Henan,China;3.College of Safety Science and Engineering,Henan Polytechnic University,Jiaozuo 454000,Henan,China
Abstract:To address the problem of large error in the calculation of long hole restoration parameters for exis-ting self-propelled rotary drill hole restore theory,a borehole restoration equation of motion was establised based on Newton’s law of variable mass,and the relationship between restoration length and hydraulic parameters,borehole parameters and pipe parameters was derived.System resistance test experiments were carried out,the effects of borehole length,angle,return water and movement speed on the integrated friction coefficient k were clarified.The equation of motion was revised and validated through self-propelling drill borehole restoration experiments.The results showed that:The integrated friction coefficient k was the key parameter of the equations of motion;The system resistance linearly increased with increasing restoration distance during the movement of the self-propelling drill;Return water created resistance to the drill and high pressure hose,resulting in an increase in the integrated friction coefficient k;As the drill and high-pressure hose moved through the upward borehole,the component force of gravity became the resistance;The increase in the angle of the borehole and jet pressure could lead to an increase in the return water flow rate,resulting in an increase in the integrated friction coefficient k;The theoretical value of the integrated friction coefficient k needed to be corrected by a factor of 0.8;The modified equation of motion allowed for a more accurate calculation of the maximum restore distance of a self-propelling drill,the error between the theoretical and experimental values was 5.7 m at a restoration distance of 104.7 m,which verified the feasibility of applying the borehole restoration for self-propelling drill technology in long boreholes.
Key words:borehole restoration;water jet;self-propelling;restoration distance;change of resistance;gas extraction
自进式旋转钻头钻孔修复运动方程及关键参数研究_刘勇.pdf