Tests validate new drill pipe buckling model
Résumé
A new drill pipe buckling model provided excellent predictions for each full-scale buckling test performed, not only in terms of deformed buckling shape but also in terms of weight transfer. Existing models, on the other hand, failed to predict observed drill pipe buckling behavior. This is the first time in the drilling industry that a buckling model was successfully validated in the field, and this model can predict realistically the onset and severity of buckling for any 3D trajectory. Many articles discuss buckling inside a wellbore but an increasing number of field observations suggest that existing buckling theories fail to predict buckling phenomenon such as lockup. Indeed, existing buckling theories generally assume that the wellbore is idealistically perfect without any doglegs. Recent advancements in drillstring mechanics modeling have demonstrated that doglegs, friction, and rotation affect greatly the buckling phenomenon. This article compares results of full-scale buckling tests with a new buckling model that takes into account actual wellbore tortuosity.