Abstract
Solid Expandable Tubular (SET) has been proven a promising technology in overcoming several unresolved challenges like isolating unwanted substances, sidetracking, well repair, and patching in horizontal wells. A novel multistage expansion system of SET is found to be an efficient way of reducing expansion cost while conserving tubular structural integrity. However, due to the complexity of multistage system, an estimation of post-expansion properties of tubular, especially in variable physical conditions, becomes a challenge in making the technology viable and cost-effective. In the current work, numerical modeling is utilized to evaluate the effects of multiple physical conditions, tubular-mandrel contact and tubular's boundary conditions on the postexpansion properties of tubular. Initially, a finite element model of multistage tubular-mandrel system is developed using the real well conditions in finite element software ABAQUS. The real boundary conditions of tubular at the field, fixed-free and fixed-fixed, are incorporated in finite element model. Moreover, a nonlinear material model, using the experimental results of uniaxial tensile tests, is used to model tubular's material behavior, while mandrel is considered as rigid body. A surface-to-surface contact conditions are defined through Coulomb's friction law with varying coefficient of friction. The finite element simulation results are compared with the experimental observations of single-stage tubular-mandrel system and found to be in good agreement. Finally, further simulations are performed to evaluate the deformation behavior of tubular using contact pressure, equivalent stress, tubular thickness variation, length shortening, and equivalent plastic strain. It is observed that the contact and boundary conditions of tubular have significant effects on tubular post-expansion properties.