FANN 206889
The Marsh Funnel is a simple device for indicating viscosity on a routine basis. When used with a measuring cup, the funnel gives an empirical value for the consistency of a drilling fluid. The number obtained depends partly on the effective viscosity at the rate of shear prevailing in the orifice, and partly on the rate of gelation.
In addition to the Marsh Funnel, this viscosity procedure requires a graduated container to receive the fluid as it flows from the funnel, a device to measure elapsed time, and a thermometer for measuring sample temperature.