Finite Element Simulations of Working Characteristics of Solid Expandable Tubular Threaded Joint

The performance of solid expandable tubular threaded joint is affected by complicated factors such as material property change, large deformation of geometric dimension and residual stress. Given material nonlinearity, geometrical nonlinearity and contact nonlinearity in the operational process of solid expandable tubular threaded joint, MSC/Marc software was adopted in this paper to conduct simulation study on the sealing property of the threaded joint during expansion and joint strength of the threaded joint after expansion. It was recognized that the solid expandable tubular threaded joint should adopt hook-shaped thread with a negative angle for the bearing surface, the sealing property of metal-to-metal cone seal would decline after expansion of the joint, and the solid expandable tubular threaded joint ought to adopt the rubber-seal-orientated sealing form. Furthermore, it was also found out that the internal thread and the root of the external thread were the vulnerable parts of the solid expandable tubular threaded joint, and the joint would first break down and cease to be effective on these parts under excessive tensile load.