Safety Analysis of Casing with Considering Strength Degradation in Steam-Injection Well

Abstract:

Casing damage is a very severe problem in steam-injection well due to thermal stress. In this paper, the computational model of casing-cement-formation coupling system is established. Considering strength degradation of casing, the temperature field and stress field are coupled to calculate casing stress. Related factors, such as concentric casing, cement thickness, casing specification and internal pressure, are considered to analyze casing safety. The results show that yield strength of N80 casing reduces as a linear function with temperature variation. There is little effect of cement thickness and casing specification on the thermal stress. Von Mises stress decreases with increase of steam injection pressure in wellbore as the casing doesn't yield. Based on the results, some measures against casing damage are presented.

• Periodical: Applied Mechanics and Materials (Volumes 155-156)
• Pages: 1000-1004
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.155-156.1000
• Online since: February 2012
• Authors: Hua Tong, Xiao Hua Zhu, Shao Hu Liu, Chang Shuai Shi
• Keywords: Casing Damage, Safety Analysis, Steam-Injection Well, Strength Degradation

References

[1] Zhonghong Yu, Liyang Wang, Dawei Liu. Investigation on production on casing in steam-injection wells and the application oilfield. Journal of Hydrodynamics, 21(2009)77-83.

DOI: 10.1016/s1001-6058(08)60121-3

[2] Xiaohua Zhu, Shaohu Liu, Changshuai Shi, et al. Successful Application of the New Double-effect Protector in Deep Well Drilling. 2010, SPE 130924.

DOI: 10.2118/130924-ms

[3] Zifeng Li. Casing cementing with half warm-up for thermal recovery wells. Journal of Petroleum Science and Engineering, 61 (2008) 94-98.

DOI: 10.1016/j.petrol.2008.05.003

[4] Catalin Teodoriu, Gioia Falcone. Comparing completion design in hydrocarbon and geothermal wells: The need to evaluate the integrity of casing connections subject to thermal stresses. Geothermics, 38 (2009) 238-246.

DOI: 10.1016/j.geothermics.2008.11.006

[5] Saeed Salehi, Geir Hareland, Keivan Khademi Dehkordi, et al. Casing collapse risk assessment and depth prediction with a neural network system approach. Journal of Petroleum Science and Engineering, 69 (2009) 156-162.

DOI: 10.1016/j.petrol.2009.08.011

[6] Suping Peng, Jitong Fu, Jincai Zhang. Borehole casing failure analysis in unconsolidated formations: A case study. Journal of Petroleum Science and Engineering, 59 (2007) 226-238.

DOI: 10.1016/j.petrol.2007.04.010

[7] Zhaohui Wang, Zhaozhong Ma. Effect by thermal well temperature on casing properties and calculation method for pretension. Steel pipe, 36 (2007) 24-27.

[8] Zhonghong Yu, Dawei Liu, Liyang Wang. Numerical simulation and industrial application of the production casing stress inside steam injection wells. Mechanics in Engineering, 30(2008) 66-69.