Abstract
The connection and sealing performances of two special tubing connectors have been revealed for selection and structure modification, which were designed for use in ultra-deep, sulfur, high pressure wells. This study has used the finite element method to compute the stress and contact pressure of the Premium Shouldered connector under different loads, including the tension, internal pressure and combined load. It showed that the high contact pressure appeared on shoulder and sealing surface / spot once the connector was made up. The shoulder extrusion site and the root of first thread having the maximum Von Mises stress were in plastic state. When the tensile load increased, the stress in the root of first thread at the big end of the tubing enlarged, and the maximum contact pressures on shoulder surfaces decreased form 1172.0 MPa and 1477.0MPa to 254.9 MPa and 438.9 MPa for PSC-?and PSC-?respectively. The sealing performance of shoulderdegraded and the sealing surface / spot played a major role. Additionally, the worst load conditions affecting the sealing and connection performances were tension load and combined load of “tension + internal pressure” respective, and both kinds of connectors could meet the performance requirements when the loads were 900 kN and 800 KN+40 MPa.
