Analytical calculation method for predicting compression deformations and sealing performance of subsea connector under operating condition

Abstract

Keeping the sealing capacity under operating conditions is of vital importance for subsea connectors, which are the key connection facilities in subsea production systems. The finite element method (FEM) is usually adopted to evaluate the sealing performance and structural strength after determining structural design parameters. However, since the design is an iterative process, the efficiency of this evaluation method is relatively low. This paper proposes an analytical calculation method (ACM) which can quickly predict compression deformations and sealing performances of the gasket under operating conditions. Theoretical relationship equations are developed among the compression under preloading conditions, the variations of the compression and the unknown contact load under operating conditions. Consequently, the contact load under the operating condition is obtained first, then contact width, contact pressure and structural stresses are determined. Finally, compression deformations and sealing performances of the subsea connector under operating conditions are estimated explicitly. Case studies under various conditions are performed to verify the consistency of the FEM and the ACM. The predicted results including compression amount, sealing parameters and structural stress are in good agreement. This work provides a theoretical method and guidance for the engineering design of subsea connectors.