Abstract
Researchers seldom study the optimum design of a mechanical connector for subsea oil-gas pipeline based upon the sealing performance. An optimal design method of a novel subsea pipeline mechanical connector is presented. By analyzing the static metal sealing mechanism, the critical condition of the sealing performance is established for this connector and the formulation method of the contact pressure on the sealing surface is created. By the method the minimum mean contact pressure of the 8.625 inch connector is calculated as 361 MPa, which is the constraint condition in the optimum design of connector. The finite element model is created in ANSYS Parametric Design Language (APDL) and the structure is optimized by the zero-order method, with variance of contact pressure as the objective function, and mean contact pressures and plastic strains as constraint variables. The optimization shows that variances of contact pressure on two sealing surfaces decrease by 72.41% and 89.33%, respectively, and mean contact pressures increase by 31.18% and 52.84%, respectively. The comparison of the optimal connectors and non-optimal connectors in the water pressure experiments and bending experiments shows that the sealing ability of optimized connectors is much higher than the rated pressure of 4.5 MPa, and the optimal connectors don’t leak under the bending moment of 52.2 kN·m. This research provides the formulation to solve contact pressure on the sealing surface and a structure optimization method to design the connectors with various dimensions.
Highlights
The depletion of onshore oil-gas resource makes more attention paid to offshore oil-gas exploitation, to the development of subsea resources [1]
This paper presents an improved design of subsea pipeline mechanical connector (SPMC) that can be used for a bigger diameter and a higher pressure in the complicated subsea environment
3.1 Sealing Mechanism The static metal seal is adopted in SPMC
Summary
The depletion of onshore oil-gas resource makes more attention paid to offshore oil-gas exploitation, to the development of subsea resources [1]. In the design of a connector with gasket, the gasket factor and minimum gasket seating stress should be determined according to the design codes [13, 14] subject to gasket material and structural These codes are based on a series of assumptions and might not define calculation procedures for sealing performance in detail [15]. Zhao et al [18], established the mathematical relationship between the contact stress of metal sealing ring governing the sealing performance, the structural parameters and operating pressure, but did not consider the plastic deformation of metallic gasket. By finite element analysis and experiment, Noga et al [27] proved the suitable contact pressure and width of plastic deformation were the key parameters to guarantee the sealing performance of flange connection without gasket. The optimization is conducted by the zero-order method in ANSYS and water pressure experiments and bending experiments are carried out
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
