摘要
在非均匀载荷作用下套管易挤毁失效,特别是在软岩层段中该问题尤其突出。为此,文中建立了非均匀地应力下、考虑水泥环界面不同接触状态的软岩层、水泥环和套管组合体力学模型,应用弹性力学半逆解法推导了水泥环和套管的应力、位移表达式,采用数值方法进行了求解。以某地区软岩层为例,研究了水泥环界面接触状态、地层力学参数、水泥环力学参数及几何参数、套管几何参数对套管受力的影响规律。研究表明,当界面完全接触时,套管受力最佳;当界面光滑接触时,套管受力最恶劣;在水泥环界面良好接触的条件下,提高水泥环力学性能、增加套管壁厚能改善套管受力。该模型及其力学分析程序可为非均匀地应力下固井工程设计提供参考。
Under non uniform in-situ stress casing collapse failure often happens. Especially in soft rock the problem is more serious. So the mechanical model of the continuous body composed of soft formation, sheath and casing considers the contacting situation of the boundary between the casing and the sheath, and the stress and displace equations are derived by the semi-analytical method. The expression of the stress and displacement of casing and cement sheath were obtained. Taking the soft rock for an example, the effect of the contact state of cement sheath boundary, formation mechanical parameters, geometrical parameters of cement and casing geometrical data on casing's force were studied. The results show that casing's force is desirable under complete contact, and casing's force is the worst under smooth contact. So enhancing the mechanical property of cement sheath and increasing the wall-thickness of casing can improve casing's force.The model and mechanical analysis program of this paper provide reference for the engineering design of well cementing.
出处
《石油钻采工艺》
CAS
CSCD
北大核心
2006年第5期7-9,共3页
Oil Drilling & Production Technology
基金
四川省杰出青年学科带头人培养基金(06ZQ026-028)
石油科技中青年创新基金(05E7044)资助
石油管力学和环境行为重点实验室项目"复杂工况下套管柱失效几个关键影响因素的研究"中的部分内容
