【作者】 陈会军；

【导师】 唐立强；

【作者基本信息】 哈尔滨工程大学 ， 固体力学， 2002， 博士

【摘要】 随着各种强化采油手段的实施，油水井套管的工作环境日益恶化，套管损坏已经成为一个石油工程关注的热点问题之一。目前套损速度有逐年增加的趋势，严重影响了各大油田的生产，造成人力、物力和财力的巨大损失。研究油水井套管损坏机理具有重要的理论意义和工程意义。 油水井套管损坏问题是一个涉及地质力学、固体力学、流体力学及材料强度理论等多门学科和领域的复杂问题。现场调查表明，套管剪切损坏是套损最严重的破坏形式之一，在采油过程中油藏结构变化打破了原地应力场的平衡，泥岩层吸水蠕变产生地层滑动是引起套管损坏的主要原因。因而研究泥岩层吸水的物性变化，即建立泥岩本构方程和分析套管剪切损坏的力学机理是倍受油田关注而急待解决的问题。围绕这一问题，本文的主要工作有以下几个方面： 1．通过分析和调研，认识到油藏结构变化和泥岩层蠕变滑动是引起套管剪切损坏的基本原因。全面地总结油水井套管损坏机理和岩土力学中的本构方程理论，为本文的工作奠定了基础。 2．深入地研究了泥岩吸水的物理变化过程，指出体积膨胀非线性变化是泥岩吸水过程物理变化的重要特征，建立了反映这一变化影响的非线性蠕变材料的本构方程。 3．建立了套管剪切损坏的油藏隆起和岩石层面滑动力学模型。应用断裂力学理论，通过理论分析和计算，给出应力和应变场的分布，定量地合理地阐明了套管剪切损坏力学机理。 4．对在采油工程中采用的预防、控制油水井套管剪切损坏的措施提供了合理的解释和定量的分析。从理论上进一步提出了一些合理的预防措施和办法。 由于套损速度有逐年增加的趋势，目前，大庆油田每年都有600-700口井发生套管损坏，直接经济损失上亿元。本论文进行了探索和研究为最终解决套管损坏问题提供了理论上的参考依据。更多还原

【Abstract】 With the adoption of various strengthened oil-extraction measures,the working conditions of casings of oil and water wells have become more and more deteriorated;the failure of casings of well is one important problem in oil engineering. Casing failure brings about enormous losses of manpower,material resources and financial resources to oilfields. Researches on the mechanism of casing failure have both theoretical and engineering significance.Casing failure is a complex problem involved with geo-mechanics,solid mechanics,fluid mechanics,material strength and theories in some other fields. The data of casing-failed wells,which are collected from DaQing Oil Field,indicates that shear failures of casing of wells is very serious. The change of construction of reservoir compaction in oil-extraction which a is due to the unbalance of the crust stress fields and the creep and gliding of mudrock layer used water-injection techniques are the main reasons of casing failure. The mechanical property of mudrock in condition of water-injection. Researches on the mechanical property of mudrock in condition of water-injection,the constitutive equation are constructed and the mechanical mechanism of casing shear failure is an urgent task to be accomplished. Research items in this dissertation are as follows.1. Through investigation and analysis,that the change of construction of reservoir compaction and the creep and gliding of mudrock layer are the main reasons of casing shear failure is studied. The mechanical mechanism of casing shear failure and theory of constitutive equation of rock-soil mechanics are summarized,which is foundation of research in this dissertation.2. The mechanical property of mudrock in condition of water-injection is studied. That change of the nonlinear bulk strain is important character in condition of water-injection of mudrock. The nonlinear creeping constitutive equation of mudrock which influences bulk expanding is established.3. Mechanical models of reservoir hunch and the creep and gliding of mudrock layer are established. Using theory of fracture mechanics and through theoretic analysis and calculation,the distribution of strains and stresses is given,which illustrates in reason the mechanical mechanism of casing shear failure.4. Some practical measures to prevent casing failures in suit are reasonably interpreted and confirmed by the theoretical results in this dissertation. From theory,some measures and rationalizationproposal to prevent casing failures are put forward further.The casing failure is increasingly aggravated year by year and there are about 600 to 700 casing-failed wells or a loss of more than a hundred million Yuan in DaQing oil field every year. The research and exploration in this dissertation can serve as reference for solution of casing failure in oil fields.更多还原