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Brookfield viscometer

1. n. [Drilling Fluids]
A cone-and-plate rheometer designed to measure viscosity of non-Newtonian fluids at low shear rates and with more accuracy than is attainable with a 6-speed, direct-indicating viscometer. Such low shear-rate data are needed for designing muds with improved hole-cleaning properties and to minimize sag of weighting material. (Brookfield is a mark of Brookfield Engineering Laboratories, Inc.)