Casing Collapse Mechanism in Geothermal Drilling in Western Turkey

Abstract

Casing collapse is a costly drilling and well completion problem that may result in wellbore loss or require very challenging repairs, taking a long time without a guarantee of restoring the well to its original condition. Casing collapse typically occurs just after the well completion process, during the warm-up of the wells for cleaning purposes, or after long-term production from the well. This study comprehensively evaluates well parameters, drilling and completion operations, and measurements taken before and after drilling in western Anatolia, Turkey. The most significant impacts were found to be related to poor cementing jobs and casing deformation due to corrosive geothermal fluids and the mobilization of formation particles caused by high fluid extraction from the reservoir.