深井超深井地层水泥环特性对套管载荷的影响  

Impacts of cement sheath on casing load in deep and ultra-deep wells

作　　者：卢亚锋 唐庚 刘殿富[2] 林元华[3] 于林 

机构地区：[1]中油西南油气田公司,四川广汉618300 [2]中油川庆钻探工程有限公司,四川成都610051 [3]西南石油大学,四川成都610500

出　　处：《特种油气藏》2010年第5期116-118,共3页Special Oil & Gas Reservoirs

基　　金：“新世纪优秀人才支持计划”(NCET-08-0907);四川省杰出青年学科带头人培养基金(06ZQ026-028)

摘　　要：由于软岩层在深井高温高压环境下具有一定的流变性,为了更加真实地反应不同地层岩性情况下水泥环特性对套管外载的影响,采用有限元方法建立了套管-水泥环-地层组合体三维空间有限元模型,研究了不同地层岩性情况下套管载荷的差异,同时结合实例分析水泥环弹性模量和泊松比对套管载荷的影响。研究认为,在岩性较软的地层,应优选刚度较大的水泥环,可帮助套管抵御一部分外载;在地层岩性较硬时,应该降低水泥环刚度,有助于吸收一部分外挤压力,达到保护套管的目的;在深井超深井固井过程中应根据不同地层情况适时调整水泥浆特性,以降低套管外载,保证油气井安全。Soft rock has certain rheological characteristics under deep well HTHP condition. A 3D model of finite elements is built by the combination of casing-cement sheath-formation to study the impacts of cement sheath on casing load under different lithologies,including the impacts of elastic modulus and Poisson ratio of cement sheath on casing load. The study shows that in a formation with soft lithology,the cement sheath shall have higher stiffness to help casing withstand a part of load; while in a formation with hard lithology,the stiffness of the cement sheath shall be reduced in order to absorb a part of external pressure and to protect casing. The property of cement slurry shall be adjusted according to formation conditions in the process of cementing deep and ultra deep wells to reduce casing load and ensure the safety of oil and gas wells.

关 键 词：深井 有限元 水泥环 套管 载荷 塔里木油田 羊塔克区块 

分 类 号：TE256[石油与天然气工程—油气井工程]