石油学报 ›› 2011, Vol. 32 ›› Issue (6): 1067-1071.DOI: 10.7623/syxb201106022

• 石油工程 • 上一篇    下一篇

晶格膨胀剂对水泥-套管界面胶结性能的影响实验

步玉环  柳华杰  宋文宇   

  1. 中国石油大学石油工程学院  山东青岛  266555
  • 收稿日期:2011-05-02 修回日期:2011-08-02 出版日期:2011-11-25 发布日期:2012-01-17
  • 通讯作者: 步玉环
  • 作者简介:步玉环,女,1966年2月生,2005年获中国石油大学(华东)油气井工程专业博士学位,现为中国石油大学(华东)石油工程学院教授,主要从事油气井工程的教学及科研工作。
  • 基金资助:

    国家高技术研究发展计划(863)项目(2006AA09Z340)和国家支撑计划课题(2008BAB37B03-3)联合资助。

Experimental study on effects of lattice expansive agent on cement-casing interfacial bonding quality

BU Yuhuan  LIU Huajie  SONG Wenyu   

  • Received:2011-05-02 Revised:2011-08-02 Online:2011-11-25 Published:2012-01-17

摘要:

水泥石体积收缩会严重影响水泥-套管界面的胶结强度,而晶格膨胀剂可以弥补水泥石体积收缩,但晶格膨胀剂能否改善水泥-套管界面胶结强度有待进一步研究。利用自行设计的界面胶结强度测定仪定性地测量了膨胀水泥与套管的剪切胶结强度,同时研究了温度和压力变化条件下膨胀水泥与套管的胶结性能,并与常规水泥进行对比,探讨了膨胀水泥与套管界面的微观结构与界面胶结强度宏观力学行为的关系。研究表明:晶格膨胀剂的加入使得水泥-套管界面胶结强度明显下降;同时,晶格膨胀剂使水泥石的弹性模量增大,使水泥-套管界面胶结强度抵抗温度和压力变化的能力变差。为了满足开发过程中温度、压力改变条件下的固井界面封隔特性要求,研究一种既能实现膨胀功能、又能改善界面胶结力和水泥石力学性能的膨胀剂具有重要的意义。

关键词: 水泥石体积收缩, 晶格膨胀剂, 水泥-套管界面, 胶结强度, 实验研究

Abstract:

Cement-sheath shrinkage after the injection of cement slurry in an annulus has a detrimental effect on cement-casing interface. A lattice expansive agent can make up for the cement-sheath shrinkage, further studies, however, are needed on whether or not the lattice expansive agent can improve the consolidation strength of cement-casing interface. In this paper, we used a self-designed testing device to qualitatively measure the shear-cementing strength between expansive cement and casing, studied consolidation properties with variations in temperature and pressure, and compared the expansive cement with conventional one. In addition, a relationship between microstructures of cement-casing interface and macroscopic mechanical behaviors of interface consolidation was investigated. The results showed that the addition of lattice expansive agent could significantly reduce the consolidation strength of cement-casing interface and increased the elastic modulus of cement sheath, which could weaken the resistance of the cement-casing interface consolidation strength to variations in temperature and pressure. In order to meet the requirement of temperature and pressure conditions encountered in exploitation, it is significant to develop a new expansive agent that can be expansible and of help to improving the interfacial consolidation strength and mechanical properties of cement sheath.

Key words: cement-sheath shrinkage, lattice expansive agent, cement-casing interface, cementation strength, experimental study