Affect of Casing Eccentricity on Stress at the Cement Ring Interface

Abstract:

In the process of the oil and gas well construction work such as casing pressure test、fracturing, etc. Casing and cement ring induration will be resulted in stress and deformation response. Under the condition of high load, may be give rise to the body damage of cement ring, and cementing interface tear and other forms of structural failure, also the function of cement ring sealing was endangered. The casing-cement ring-strata finite element mechanics model was established by using the mechanics theory and finite element theory in this paper. The affect of casing eccentricity on stress at the cement ring interface was analyzed. The results showed that, the greater eccentricity, narrow gaps of cement stone was easier to be crushed after load when the load value was near to the in-situ stress.The greater the degree of the eccentricity, narrow gaps of cementation interface was easier to be tore after unload when the load value differ greatly with the in-situ stress.

• Periodical: Advanced Materials Research (Volume 1088)
• Pages: 829-833
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1088.829
• Online since: February 2015
• Authors: Jing Fu Zhang*, Bo Wang, De Bing Zhang, Xun Wang
• Keywords: Cement Ring, Cementing Interface, Eccentricity, Stress

References

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