采动影响下煤层气井失稳机制及防失稳技术探讨  

Discussion on instability mechanism and anti-instability technology of coalbed methane wells under the influence of mining

作　　者：杨婧 蔡峰[1] 封居强 YANG Jing;CAI Feng;FENG Juqiang(State Key Laboratory of Mining Response and Disaster Prevention and Control in Deep Coal Mines,Anhui University of Science and Technology,Huainan,232001,China)

机构地区：[1]安徽理工大学深部煤矿采动响应与灾害防控国家重点实验室,安徽淮南232001

出　　处：《华北科技学院学报》2022年第1期38-43,共6页Journal of North China Institute of Science and Technology

基　　金：安徽省高校协同创新项目(GXXT-2020-057)。

摘　　要：地面煤层气井稳定性是地面钻井瓦斯抽采效果的关键因素。研究采动影响下煤层覆岩运动对钻井的失稳影响机制十分重要。本文分析了覆岩“竖三带”的运动演变形式,总结了采空区瓦斯抽采地面钻井的失稳机制,并针对淮南矿区地面钻井抽采瓦斯技术的现状,从三个角度探讨地面钻井防失稳技术措施。针对钻井终孔垂高应预设在裂隙带中,对于井位选择提出“两减”原则,对于钻井结构防失稳措施提出“四增”原则。为解决地面钻井瓦斯抽采技术难题提供新思路。The stability of surface coalbed methane wells is a key factor in the effect of surface drilling gas extraction.Therefore,it is necessary to study the impact mechanism of coal seam overlying rock movement on drilling instability under the influence of mining.This paper analyzes the movement and evolution of the"three vertical zones"of the overlying rock,summarizes the instability mechanism of surface drilling for gas extraction in the goaf,and discusses surface drilling from three perspectives in view of the current status of surface drilling and gas extraction technology in Huainan mining area Technical measures to prevent instability.In view of the vertical height of the final drilling hole should be preset in the fracture zone,the principle of"two reductions"is proposed for the selection of drilling location,and the principle of"four increases"is proposed for the wellbore structure anti-instability measures.Provide ideas for solving the technical problems of surface drilling gas drainage.

关 键 词：地面钻井 失稳机制 终孔垂高 井位选择 钻井结构 

分 类 号：TE254[石油与天然气工程—油气井工程]