SHEAR THICKENING FLUID

摘要

SHEAR THICKENING FLUID (C-833) The instant invention is directed to shear thickening fluids which comprise a water swellable granular material (clay) present in sufficient quantity so as to be capable of rapidly forming a stiff paste, having a strength of at least 2000 lbs/100 ft.2 upon interaction with the aqueous phase used, a nonaqueous hydrophobic material comprising a hydrocarbon material and a surfactant and/or a strengthening agent, and an aqueous solution comprising water and a water-soluble/water-swellable polymer, wherein the granular clay and water-polymer solution are kept separated the intervening hydrocarbon-surfactant composition. Discrete particles of granular clay are encapsulated in the oil phase and individual droplets of water-polymer are also encapsulated in the oil phase resulting in an oil continuous phase composite. The intervening oil phase prevents the interaction between the water-polymer and the granular clay phases and results in a stable, nonreacting, pumpable composite until such time as the oil envelope is ruptured by application of a sufficiently high shear force. Upon such rupture, the materials interaot resulting in the semi-rigid high strength paste. Various well control problems as such as oil and gas blowouts, can be controlled by use of the abovedescribed composite. The composite is pumped down the well pipe. Exiting the orifices of the drill bit supplies the shear force needed to rupture the oil envelope thereby permitting the interaction between the clay and the waterpolymer resulting in the formation of the semi-rigid paste having a strength of at least 2000 lbs/100 ft,2 which seals The unwanted flow or flow channels either in or immediately adjacent to the wellbore.