Bore-Plate Shale Stabilizer was developed by American Gilsonite Company with three main objectives in mind. These are: excellent shale stability, excellent reaction in a water environment (drilling fluid), and easy dispersability. These objectives were achieved and tested under the guidance of Chevron’s Drilling Technology Center using the O-G-S Downhole Simulation Cell (DSC) in Houston, Texas.
First, tests showed that maximum shale stability would be achieved with different softening points of Gilsonite® depending on the bottom hole temperature. To achieve a product that would work under a wide range of downhole temperatures, several softening points and different quantities of Gilsonite were tested. Further testing in the DSC determined the optimum mix of high vs. low melting point materials in the final product.
Secondly, good reaction in a water environment requires surfactants with a strong lipophilic head and a strong hydrophilic tail. Extensive testing identified a surfactant with a strong lipophilic head which reacts with the Gilsonite and attaches very tenaciously to the powder. At the same time, the hydrophilic tail allows the Gilsonite powder to become easily dispersed in water. In addition, the surfactant provides excellent rewettability and allows for prolonged product storage.
Finally, AGC looked at the best dispersability in a drilling fluid system. A special component was added to make Bore-Plate more readily dispersible.
Bore-Plate is a unique, versatile product. It provides excellent shale stability and at the same time helps minimize stuck pipe caused by differential pressure sticking. It effectively seals off sand formations by forming an intermatrix filter cake. Bore-Plate is easily dispersed in most drilling fluid systems and its strong surfactant prevents reactions which could affect wettability and cause coalescing.