大直径救援井干孔透巷关键技术及应用

Key technology and application of dry hole drilling for roadway penetration in large diameter relief well

为了实现地面大直径救援井安全透巷,在大直径井覆盖层和基岩层常规泥浆正循环、多级扩孔钻进基础上,研究了影响大直径救援井干孔透巷因素,主要包括反循环环空压力控制、反循环透巷遇强-弱含水层、透巷段预留安全距离及高效固完井方式。通过重点分析预留透巷段干孔透巷钻进技术原理、干孔透巷反循环装置、透巷分段排浆排渣钻进、安全透巷工艺、透巷位置选择及透巷距离确定,形成了一整套针对大直径干孔透巷高效钻进关键技术体系,实践验证效果良好,为地面大直径救援井干孔透巷钻进提供了技术支撑。

In order to ensure the surface-drilled large-diameter relief well safely penetrate the roadway,we studied the factors affecting the dry hole penetration on the basis of conventional mud direct circulation and multi-stage expansion drilling in the cover layer and bedrock layer of the large-diameter well.These main factors are reverse circulation annular pressure control,reverse circulation penetration when encountering strong or weak aquifers,reserved safety distance in the penetration section,and efficient cementing completion method.By analyzing the principle of dry hole drilling technology in the reserved penetration section,the reverse circulation device,the segmented slurry and slag discharge drilling,the safe roadway penetration process,determination of the penetration position,and penetration distance,we obtained a complete set of key technology system for efficient drilling of large diameter dry hole roadway penetration,which has received good practice results,and can provide technical support for the dry hole roadway penetration of surface-drilled large diameter relief well.