Metal sealing performance of subsea X-tree wellhead connector sealer

Zhao, Huimin; Chen, Rui; Luo, Xiaolan; Duan, Menglan; Lu, Yinghui; Fu, Guowei; Tian, Hongping; Ye, Daohui

doi:10.3901/cjme.2015.0309.026

Cited by 26 publications

(13 citation statements)

References 5 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…From Eqs. (9) and (10), the relationship between the preload seal contact stress and the amount of radial deformation was obtained:…”

Section: Mechanical Analysis Of the Metal Seal Ringmentioning

confidence: 99%

“…Therefore, the finite element model was created using the ANSYS Parametric Design Language (APDL), and the structure was optimized with the zero-order method. Zhao et al [9] analyzed the metal sealing performance of the subsea X-tree wellhead connectors at a pressure of 34.5 MPa, while also investigating the influence of preload force and internal pressure on contact stress. Wei et al [10] used the superposition theorem of elasticity to deduce the formula of the critical mean contact pressure of a mechanical subsea pipeline connector.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Metal sealing mechanism and experimental study of the subsea wellhead connector

Zhao

Wang

et al. 2019

J Braz. Soc. Mech. Sci. Eng.

Self Cite

View full text Add to dashboard Cite

The subsea wellhead connector is an essential piece of equipment whose successful metal-to-metal sealing capacity is crucial to produce deep-sea oil and gas safely. This paper analyzed the mechanical behavior of the metal seal ring in the subsea wellhead connector under preload and operating conditions while determining the role of contact stress in the theoretical relationship between the seal ring and the structural parameters, as well as working pressure. Theoretical calculations and the finite element method were used to analyze the effects of preload force, contact width, preload compression, and working pressure on contact stress. The results derived from the finite element approach were consistent with those obtained with the theoretical calculation method. Finally, the contact width and preload compression parameters of the metal seal were tested by constructing a test device to evaluate the metal seal of the subsea wellhead connector. The relationship between the preload force, contact width, and preload compression was analyzed, and the maximum sealing pressure under different preload forces was investigated. The results verified the accuracy of the theoretical and finite element calculations. This paper proposed the theoretical calculation method for designing and analyzing the metal seal of the subsea wellhead connector.

show abstract

“…From Eqs. (9) and (10), the relationship between the preload seal contact stress and the amount of radial deformation was obtained:…”

Section: Mechanical Analysis Of the Metal Seal Ringmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Metal sealing mechanism and experimental study of the subsea wellhead connector

Zhao

Wang

et al. 2019

J Braz. Soc. Mech. Sci. Eng.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Subsea production systems are mainly composed of subsea trees, subsea manifolds, subsea well control systems, and subsea processing systems [1,2]. Forming the core of the subsea production system is the subsea tree, the primary function of which is to control the flow of produced oil and gas, monitor oil and gas parameters, as well as form an isolation barrier between the underground reservoir and the environment containing the subsea wellhead system [3]. The submarine environment is relatively safe compared to the sea surface, but the installation of the subsea trees is more complicated.…”

Section: Introductionmentioning

confidence: 99%

Study of the Installation Process of the Subsea Tree Passed Through the Splash Zone

Zhao

et al. 2020

Energies

Self Cite

View full text Add to dashboard Cite

The subsea tree is one of the critical pieces of equipment in the subsea production system, and its installation is related to the safe production of offshore oil and gas. Due to the differences in the form of the structures, the speed of entering the water, the marine environment, and other factors, the process of the structure entering the water is exceedingly complicated. During the engineering installation, the most dangerous phase involves the structure passing through the splash zone. Based on the theory of the movement of the subsea tree passing through the splash zone, Lingshui 17-2 subsea tree installation was analyzed with the marine engineering software OrcaFlex, and a sensitivity analysis of the lowering of the subsea tree was performed. During the splash zone phase, the wave height had the highest impact on the subsea tree, affecting the horizontal offset and cable load, which may lead to the oil tree capsizing and cable breakage. Furthermore, the velocity only affected the horizontal offset, and the overall effect was not noticeable. The operational safety window for the subsea tree installation was established according to the operational safety standards. Therefore, the recommended lowering speed was 0.50 m/s, while the flow velocity should not exceed 1.50 m/s, and the wave height should not be higher than 4.5 m.

show abstract

“…15,16 Specifically, the metal seals utilize a flexible metal seal as their external seal element to contact the internal sealed element, and then form a tight and durable seal, which can withstand the high pressure, high temperature, and corrosive-fluid conditions in oil-gas wells. [17][18][19][20][21][22][23][24] Zhao et al 25 established the theoretical relationships between the contact stress of subsea X-tree wellhead connector sealer and its independent variables. The analytical results were consistent with the simulation results well via the FEM; however, the effect of plastic deformation is not taken into account.…”

mentioning

confidence: 99%

Contact mechanical behaviors of radial metal seal for the interval control valve in intelligent well: Modeling and theoretical study

Yang

Zhu

et al. 2019

Energy Science & Engineering

View full text Add to dashboard Cite

Intelligent wells equipped with the interval control valve (ICV), which have the potential applications to significantly improve oil production or control the water production of wells and fields, are more and more widely utilized in the oilfields. The radial metal seal of an ICV is intended to isolate the flow of produced fluids between the casing annulus and the well tubing. The contact mechanical behaviors of the radial metal seal are essential to the structural design and reliability of ICVs in the intelligent well. In this paper, the two‐dimensional axisymmetric assembly of the radial metal seal and the closure member is abstracted as a combination of interference fit model and cantilever beam model. Based on that, the related theoretical model, between the radial metal seal's contact stress and its independent variables, has been derived. Next, numerically simulations of contact stress between the radial metal seal and the closure member for different independent variables are conducted by the finite element method (FEM) to validate the theoretical model. It is found that the mean absolute value of relative error between the numerical and theoretical results of the contact stress is approximately 10%. Additionally, the structural parameters of the radial metal seal are proposed with the absolute value of relative error <10%. Furthermore, the value of the contact stress based on the cantilever beam model can be used to calculate an approximation theoretical solution. In summary, the proposed theoretical model provides a foundation for the design, improvement, and selection of radial metal seal under the known oilfield conditions.

show abstract

Metal sealing performance of subsea X-tree wellhead connector sealer

Cited by 26 publications

References 5 publications

Metal sealing mechanism and experimental study of the subsea wellhead connector

Metal sealing mechanism and experimental study of the subsea wellhead connector

Study of the Installation Process of the Subsea Tree Passed Through the Splash Zone

Contact mechanical behaviors of radial metal seal for the interval control valve in intelligent well: Modeling and theoretical study

Contact Info

Product

Resources

About