Abstract
Wellbore integrity continues to be a primary concern in drilling operations due to AFE over-runs resulting from delays, and in extreme cases, re-drills when integrity is lost. In the case of tensile failure, it is vital to have a solution that is versatile, easily prepared and quickly placed to remediate a loss-of-integrity event. A one-sack, quick mix and pump fiber pill formulation has been developed that addresses these common operational concerns. Previous field trials have shown this one-sack, rapid mix and pump material to work quickly and effectively in shale- and sand-based formations.
Recently, this material has also been shown to work successfully in fractured chalk formations. Fractured-chalk formations show many similar physical characteristics to fractured carbonates, but many differences from shale and sand-based formations. This is a great leap forward in showing the versatility and applicability of this lost circulation solution because fractured carbonates are present in many of the world’s drilling areas. Through these new trials it is now evident the material is effective across most of the physical conditions encountered worldwide. These trials also contain a new and successful utilization of calcium carbonate as a weighting agent in the formulation of the one-sack rapid mix (OSRM) pill, opening a new area of utilization for this material at lower densities. The successful use of calcium carbonate, rather than barite, also enables the OSRM pill to be further customized through the use of different, and assorted, particle sizes available in calcium carbonate grinds. In addition, it is also important to note that this one-sack, lost-circulation product has been given a green environmental rating in Norway, demonstrating high environmental compliance for most markets worldwide.
