Determination of ultimate lifting capacity of drill string for ultra-deep wells based on sealing performance of tool joint

作者：Chen Feng; Di Qinfeng^*; Wang Wenchang; Wang Mingjie; Yuan Pengbin; Zhou Yongqi

来源：Acta Petrolei Sinica, 2013, 34(6): 1176-1180.

DOI：10.7623/syxb201306019

• 3D-finite element analysis
• Lifting capacity
• Sealing performance
• Tool joint
• Ultra-deep wells

In order to evaluate the sealing performance of tool joint in large axial load and ensure the usability of tool joint, a precision finite element model of double shoulder tool joint was established using three-dimensional finite method to describe the sealing mechanism of tool joint. This model could analyze mechanical characteristics of tool joints under actions of make-up torque and axial tension. The results showed that: The sealing performance of double shoulder tool joint was mainly with the primary and secondary shoulder, and rational contact pressure which was produced by the primary and secondary shoulder guaranteed the sealing performance of tool joint; Axial tension may reduce the contact pressure on the primary and secondary shoulder, which weakened the sealing performance of tool joint; When the axial tension reaches to 2500 kN, the primary and secondary shoulder would lose their sealing performance, which increased the risk of stress corrosion of tool joint. These results could be taken as a reference in determining the ultimate lifting capacity of drill string and improving the performance of tool joint.

• 出版日期2013
• 单位上海大学