Session: 04-04-02 Rigid Pipe Mechanics II

Paper Number: 128160

128160 - Theoretical and Numerical Analysis on Mechanically Lined Pipe Fabrication 

Mechanically Lined Pipe (MLP) is a double-wall pipe comprising a carbon steel outer pipe internally coated with a thin layer of Corrosion resistance Alloy (CRA). This CRA layer serves to safeguard the outer pipe against corrosive agents presented in the production fluid from offshore O&G fields. While the high-strength low carbon steel outer pipe bears majority of external loads. The process of hydroforming expansion represents the predominant technique employed in affixing the liner onto the carrier pipe. Precise and dependable theoretical models have been consistently sought for enhancing the fabrication efficiency and serving as a benchmark for subsequent failure analysis. The Tresca criterion has been employed in the stress-strain analysis of MLP due to its mathematical simplicity. Nevertheless, it is worth noting that the Tresca criterion is widely acknowledged for its conservative approach in predicting the yielding of metallic structures. Consequently, the accuracy of employing the Tresca criterion in analyzing the fabrication of MLP is arguable. To further enhance accuracy, the infinitesimal strain theory and von Mises yield criterion are applied in conducting theoretical analysis for the MLP processing. Residual contact pressure is predicted analytically through the circumferential strain compatibility method. An axisymmetric Finite Element Model (FEM) is developed for comparison with theoretical models adopting Tresca and von Mises criterion. Ultimately, the impact of introducing an appropriate level of plastification to carrier pipe on the residual contact pressure is also investigated.

Presenting Author: Rongzhi Wei Universidade Federal do Rio de Janeiro

Presenting Author Biography: Rongzhi Wei is a Chinese student with an bachelor degree from China University of Petroleum (Beijing).

Rongzhi Wei obtained his master degree in Ocean Engineering from Federal University of Rio de Janeiro (UFRJ).

Currently, Rongzhi Wei is a PhD student in Ocean Engineering focusing on the field of Offshore structure under the supervision of Prof. Murilo.A.Vaz.

Authors:

Rongzhi Wei Universidade Federal do Rio de Janeiro
Murilo Augusto Vaz Universidade Federal do Rio de Janeiro
Xuefeng Hu CNOOC Petroleum Brasil Ltda.