Influence of velocity on conductor casing driving via Material Point Method

Resumo

The conductor is the first casing settled in an oil well and it has important functions regarding the initial phase of well construction. Some of its functions are to bear loads from the wellhead, bear the surface casing during its cementation, and insulate unconsolidated formations. The soil response to the conductor settlement is an important factor, for a poor settlement may cause excessive wear on the wellhead equipment or even the loss of the well. Therefore, a simulation of the self-weight phase of a conductor driving was conducted to enhance knowledge about the soils state during this process. The soil was modeled as soft clay, and the mechanical behavior was described by the Mohr-Coulomb model. As the conductor driving results in large displacements in a short period, the traditional Finite Element Method (FEM) is unable to model this system. Therefore, the Material Point Method (MPM), which is a modification of FEM, was used to model the conductor-soil system. Three conductor velocities were simulated and the resultant force in the casing outer surface was analyzed. The soils stress state, displacement, and velocities were studied.