超深盐井系列井筒事故分析及防范技术
Analysis and prevention techniques for a series of accidents in the ultra-deep salt wells
侯秉仁 1牛耀辉 2上官拴通 2高亮 2于长富 1赵岩2
作者信息
- 1. 河北燃气有限公司,河北 石家庄 050000
- 2. 河北省煤田地质局第二地质队,河北 邢台 054000;河北省干热岩研究中心,河北 邢台 054000
- 折叠
摘要
河北省宁晋盐田存在埋藏深度大、夹层数量多、蠕变强度高等不利地质条件,对超深盐井Z井造腔试验过程中系列井筒事故进行深入分析,有利于优化该区后续钻井方案.基于宁晋盐穴造腔工程的现场通井、测井、造腔、测腔等数据,引入夹层垮塌机制、造腔中心管的场振效应、盐腔蠕变底鼓-顶沉机制、套管剪压-拉伸断破机制等理论基础,将公式解析、数值模拟结果与工程探测数据进行相互验证,分析井壁、中心管和套管的破坏机理.研究表明,测井遇阻与薄夹层快速溶垮形成的井壁"陡坎"有关;中心管失稳的主要原因是管柱的场振效应,其次是腔底蠕变上拱产生的纵向挤压作用;套管破损与腔顶蠕变下沉产生的轴向拉应变有关,而中心管的场振效应进一步加剧了该过程.研究结果在钻井及固井设计、造腔管柱及腔体稳定性设计、腔体形态控制等方面提出了改进建议,可为同类盐穴钻井设计提供技术参考.
Abstract
The Ningjin salt field in Hebei Province is characterized by unfavorable geological conditions,including significant burial depth,a high number of interlayers,and elevated creep strength.Conducting an in-depth analysis of the series of wellbore accidents that occurred during the well Z cavity creation test can facilitate the optimization of subsequent drilling plans in this area.Drawing upon data from well opening,logging,cavity creation,and cavity measurement obtained on-site at the Ningjin Salt Cavern Construction Project,we introduce theoretical foundations such as interlayer collapse mechanisms,field vibration effects of the cavity center tube,creep-induced bottom bulging and top subsidence mechanisms in salt caverns,and casing shear-compression and tensile fracture mechanisms.These theoretical foundations are cross-verified with formula analysis,numerical simulation results,and engineering detection data to analyze the causes of wellbore accidents.Research indicates that logging resistance is associated with the rapid dissolution of thin interlayers,leading to the formation of"steep slopes"in the wellbore wall.The primary cause of central tube instability is the field vibration effect of the pipe string,followed by the longitudinal compression effect resulting from creep-induced arching at the cavity bottom.Casing damage is linked to axial tensile strain caused by creep and subsidence at the cavity top,a process further exacerbated by the field vibration effect of the central tube.The research findings offer improvement suggestions in areas such as drilling and cementing design,wellbore string and cavity stability design,as well as cavity shape control,serving as a technical reference for similar salt cavern drilling designs.
关键词
盐穴储气库/夹层垮塌/造腔管柱/盐腔蠕变/套管应力Key words
salt cavern gas storage/interlayer collapse/cavity-making pipe string/salt cavity creep/casing stress引用本文复制引用
出版年
2025
NETL
NSTL
万方数据