Best Practices for Effective Wellbore Cleanup and Displacements in Open-Hole Sand Control Completions

Abstract

At some stage after drilling to target depth and before pumping the gravel packing treatment or before putting the well on production, the drilling fluid is typically displaced from the wellbore. Practices in the industry vary significantly depending on the primary drivers of the completion engineers, sometimes with disastrous results. Inefficient wellbore displacements can cause a variety of problems including increased non-productive time, reduced well productivity and incomplete gravel packing through various mechanisms. In this paper, we detail our best practices to ensure efficient wellbore displacements for sand control completions. In the design phase, these involve various compatibility tests some of which are not commonly done and/or potential problems cannot easily be identified when they are done using conventional test procedures, modeling of fluid-fluid displacements and determining the fluid properties, pump rates and fluid volumes required for effective displacements in a given wellbore geometry and flow paths. On the rig site, they involve several quality control tests, some of which have not previously been implemented.