钻井液与完井液2018，Vol.35Issue(2)：98-103,6.DOI:10.3969/j.issn.1001-5620.2018.02.016
变内压条件下膨胀水泥性能对井筒完整性的影响
Effects of Properties of Expansive Cement on Wellbore Integrity under Changing Casing Internal Pressure
摘要
Abstract
The effects of the properties of expansive cement on wellbore integrity have been studied using finite element method based on elastic mechanics theory. The study shows that cement with appropriate rate of expansion will reduce the maximum Mises stress inside casing. The higher the rate of expansion of cement, the higher the maximum Mises stress in side cement sheath, and the lower the maximum circumferential stress. When pressure exists inside casing, the higher the elastic modulus of the expansive cement, the lower the maximum Mises stress inside casing, and the higher the maximum Mises stress inside cement sheath. At lower casing pressure, the higher the elastic modulus of cement, the lower the maximum circumferential stress inside cement sheath, contrary to the situation in which the casing pressure is higher. The effects of Poisson ratio on the maximum Mises stress inside casing are lower. The higher the Poisson ratio of cement, the lower the maximum Mises stress and the maximum circumferential stress inside cement sheath. Similar pattern of the effects of the properties of expansive cement on the integrity of wellbore is found for elastic formations and creep formations. Under the circumstance of changing casing pressure, the properties of expansive cement exert greater influences on the compressive failure and circumferential tensile failure of cement sheath. These conclusions suggest that, in selecting expansive cement, the properties of the expansive cement should be taken into account, based on the actual application requirements.关键词
固井质量/井筒完整性/膨胀水泥/变内压/米塞斯应力/周向应力Key words
Job quality of well cementing/Integrity of wellbore/Expansive cement/Changing casing pressure/Mises stress/Circumferential stress分类
能源科技引用本文复制引用
郭辛阳,步玉环,李强..变内压条件下膨胀水泥性能对井筒完整性的影响[J].钻井液与完井液,2018,35(2):98-103,6.基金项目
国家自然科学基金"CCS 咸水层封存中二氧化碳 - 硫酸盐 - 镁盐协同作用下油井水泥石的腐蚀机理"(51704325) （51704325）
中央高校基本科研业务费专项资金"井下温压复杂变化条件下水泥环完整性失效的机制及评价研究"(18CX02103A). （18CX02103A）
