Water-Based Drilling Fluid Additives
Viscosity control drilling fluid additives For Water-Based Mud

Commercial clays additives are used to control the viscosity of water-based drilling fluid. These are graded according to their yield. The yield of clay is defined as the number of barrels of 15 centipoise viscosity mud which can be obtained from 1 ton of dry clay. (A 15 centipoise viscosity will support barite). Wyoming bentonite has a yield of about 100 bbl/ton, whereas native clays may only yield 10 bbl/ton.
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