A mechanism of expandable conductor used to improve the bearing capacity of subsea wellhead in deep-water drilling

被引：0

作者：

Zhang M. ^{[1
]}

Yang J. ^{[1
]}

Liu H. ^{[2
]}

Li L. ^{[1
]}

Fu C. ^{[1
]}

Yang Y. ^{[1
]}

Xu D. ^{[1
]}

Ma K. ^{[1
]}

机构：

[1] College of Safety and Ocean Engineering, China University of Petroleum, Beijing

[2] Zhanjiang Branch, CNOOC China Limited, Zhanjiang, 524057, Guangdong

来源：

Shiyou Xuebao/Acta Petrolei Sinica | 2021年 / 42卷 / 06期

关键词：

Bearing capacity; Deep-water drilling; Expandable conductor; Subsea wellhead; Wellhead stability;

D O I：

10.7623/syxb202106008

中图分类号：

学科分类号：

摘要：

Surface conductor is the main supporting structure of subsea wellheads in deep-water drilling. Complex accidents such as subsea wellhead instability and sinking are mainly caused by the insufficient bearing capacity of surface conductor. Therefore, the deep-water drilling engineering focuses on how to economically and efficiently increase the bearing capacity of surface conductor. The expandable conductor is used to improve the bearing capacity of surface conductor, after the conductor is installed at the projected depth of seafloor without changing the process conditions of installing the surface conductor by the conventional deep-water jetting method, the surface area of surface conductor in contact with the seafloor soil is increased due to the expansion of expandable material, thus enhancing the lateral friction of surface conductor and the bearing capacity of subsea wellhead. Based on the main structural composition of the subsea wellhead of deep water drilling, this paper analyzes the relationship between the size of surface conductor and the bearing capacity of subsea wellhead by establishing a calculation model for the bearing capacity of subsea wellhead in deep-water drilling, reveals the linear change between the external surface area of the expandable surface conductor and the bearing capacity of subsea wellhead, and obtains the calculation model between the thickness of expandable material and the bearing capacity of subsea wellhead. Moreover, this paper proposes that the segmented structure of expandable material can increase the bearing capacity of expandable conductor, and analyzes the influence laws of the number of sections, coverage area, and expansion thickness of expandable material on the bearing capacity of surface conductor. It is concluded that the bearing capacity of surface conductor increases linearly with the increase in the number of segments under the same coverage area, and the bearing capacity increases linearly with the increase in the expansion thickness. Through the application test of 3 deep-water wells in the South China Sea, the error between the results from the calculation model established for the drilling bearing capacity of subsea wellhead and those from the field test is about 5%. © 2021, Editorial Office of ACTA PETROLEI SINICA. All right reserved.

引用

页码：791 / 800

页数：9

共 30 条

[1] ZHANG Gongcheng, QU Hongjun, ZHANG Fenglian, Et al., Major new discoveries of oil and gas in global deepwaters and enlightenment, Acta Petrolei Sinica, 40, 1, pp. 1-34, (2019)
[2] LIU Shujie, XIE Renjun, TONG Gang, Et al., Progress and prospect of deepwater well drilling and completion technique of CNOOC, Acta Petrolei Sinica, 40, S2, pp. 168-173, (2019)
[3] XUE Yong'an, NIU Chengmin, WANG Deying, Et al., New understanding of shallow hydrocarbon migration and new exploration progress in the Bohai Sea, Acta Petrolei Sinica, 40, S2, pp. 29-37, (2019)
[4] JIA Chengzao, Development challenges and future scientific and technological researches in China's petroleum industry upstream, Acta Petrolei Sinica, 41, 12, pp. 1445-1464, (2020)
[5] YANG Jin, Calculation method of surface conductor setting depth in deepwater oil and gas wells, Acta Petrolei Sinica, 40, 11, pp. 1396-1406, (2019)
[6] YANG Jin, LIU Shujie, ZHOU Jianliang, Et al., Research of conductor setting depth using jetting in the surface of deepwater, (2010)
[7] LIU Zhengli, TANG Haixiong, WANG Yuezeng, Et al., Deep water injection catheter and practical design method, Journal of Yangtze University: Natural Science Edition, 7, 1, pp. 189-191, (2010)
[8] XU Yunjin, YANG Jin, ZHOU Bo, Et al., Research on limit depth of the surface conductor by jetting method in deepwater drilling, Oil Drilling & Production Technology, 38, 5, pp. 553-557, (2016)
[9] XU Yunjin, YANG Jin, MENG Wei, Et al., Interaction between drill bit and subsea soil during deepwater drilling pipe ejection, Oil Drilling & Production Technology, 37, 1, pp. 47-49, (2015)
[10] WEI Hongshu, YANG Jin, LIU Zhengli, Et al., Study on safety control technology of surface conductor jetting penetration in ultra-deep water soft formation drilling, The 29th International Ocean and Polar Engineering Conference, (2019)

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