Mechanical Analysis of Offshore Thermal Recovery Well Tubing Based on Multi-string Spatial Beam Finite Element Model

During offshore thermal recovery process of viscous oil, high temperature and high pressure environments pose great threat to tubing safety. But at present, there is no stress analysis method for the string of thermal fluid thermal recovery operation to analyze the stress condition of downhole string, so as to carry out strength checking and tool design. A thermal recovery tubing analysis model is established based on multi-string-spatial beam finite element method to solve the nonlinear contacts problem between tubing and wellbore. Thus, a finite element mechanical analysis method for offshore thermal tubing is formed. Through the software example analysis, the mechanical parameters of column structure of pipe during the offshore thermal recovery process, obtaining the radial displacement change with well depth, friction, axial force and safety factor along the wellbore. This method provides theoretical foundation for structure optimization design and safety evaluation of offshore thermal tubing.