Analytical calculation method for predicting contact loads and structural strength of metallic gasket of subsea connectors under thermal loads

Abstract

Identifying the effect of thermal loads that are caused by temperature differences of inner and outer fluids on the structural sealing performance and strength is a long-standing quest in the design of subsea connectors. However, the structural stress and sealing parameters of the gasket under thermal loads are difficult to analyze and calculate using the current theoretical method because the boundary conditions of the gasket’s geometry surface are contact constraints interacted by the gasket and hubs. This paper presents an analytical calculation method (ACM) that evaluates the thermal-structural coupling strength and sealing performance considering such special boundary conditions. The thermal load is converted into an equivalent compression load, that is, a concentrated force, and applied to the contact region of the gasket. Additionally, a thermal-structural coupling finite element model is proposed to verify the ACM and the results show good agreement. Taken together, this work contributes to the design of subsea connectors that more likely take thermal loads into account.

Mechanical Behavior and Sealing Performance Study of Subsea Connector Core-Sealing Components under the Combined Action of Internal Pressure, Bending Moment, and Axial Load

“…Yun et al [21] developed a heat transfer model to investigate the sealing capability of lens-type sealing structures of subsea clamp connectors under the influence of external seawater and internal oil and gas temperature loads. Meanwhile, Zhang et al [22] proposed an analytical calculation method (ACM) to evaluate the thermal-structural coupling strength and sealing performance of subsea wellhead connectors. Li et al [23] derived the radial temperature distribution function of a subsea wellhead connection and investigated the effects of internal pressure and temperature on its metal sealing capacity through experimental studies.…”