Stress Amplification Factor Analysis Methodology for Assessing Fatigue Performance of Threaded Connectors

摘要

A computer-implemented method is disclosed for characterizing a threaded coupling such as between two tubular members, e.g., casing segments employed in the field of oil and gas recovery. In one embodiment, a virtual model of the coupling is generated, and the virtual model is re-arranged to simulate plastic deformation of at least part of the coupling. The re-arranged model is analyzed to derive a stress/strain distribution of the coupling subject to subsequent loading, and an SAF (stress amplification factor) is determined from the analysis that reflects the effect of cyclic loading of the coupling. The method facilitates a thorough assessment of the performance of the coupling in fatigue.

主权项

1. A computer-implemented method of characterizing an operating performance of first and second tubular members that are connectable to one another by a threaded pin connector and a threaded box connector defined respectively thereon, the method comprising:
receiving by a computer, a virtual model of the first and second tubular members connected to one another by the threaded pin connector and the threaded box connector; applying by the computer at least one first simulated force to the virtual model, the at least one first simulated force sufficient to induce a simulated plastic deformation in at least one of the first and second tubular members of the virtual model; relieving by the computer the at least one first simulated force from the virtual model such that a portion of a geometry of the virtual model is rearranged by the plastic deformation; applying by the computer at least one second simulated force to the virtual model; and identifying by the computer at least one peak stress in the virtual model induced by the at least one second simulated force.