摘要
欠平衡钻井后实施欠平衡完井才能最大限度地保护油气层和力争自然建产。在阐述了欠平衡完井的核心问题——密封和克服上顶力及其目前可采取的技术措施的基础上,通过对欠平衡完井管柱的受力分析,推导出气体欠平衡条件下上顶力数学模型,解决了上顶力计算无依据可循的状况。通过计算分析,认为井口压力是上顶力的主要影响因素,通过对井口压力稳定控制和井口装置配套要求的系统研究,确定了欠平衡完井井口回压的合理控制范围为1～5MPa。
Implemented after underbalanced drilling, the underbalanced completion can not only protect oil and gas formations but also attempt a natural production-construction to the maximum extent. In this paper, the key problems about underbalanced completion of both sealing and overcoming of upper jacking force are presented at first; and then, the force from string is analyzed and a mathematical model of upper jacking force is derived; it is considered from force calculation that wellhead pressure is the key factor affecting upper jacking force; a reasonable controlling range for wellhead backpressure is determined from 1 to 5 MPa; at last,some conclusions which can guide completion are also achieved for gas wells.
出处
《天然气技术与经济》
2011年第6期36-39,78-79,共4页
Natural Gas Technology and Economy
关键词
气井完井
欠平衡
压力控制
上顶力
井口套压
gas-well completion, underbalanced, pressure control, upper jacking force, wellhead casing pressure
