The Marsh Funnel is a simple device for indicating viscosity on a routine basis. When used with a measuring cup, the funnel give

The Marsh Funnel readings are only  general measurements, but the frequent reporting of the Marsh Funnel Viscosity will alert the mud engineer to sudden changes in the mud viscosity that could require corrective action.

The Marsh Funnel Viscosity is the ratio of the speed of the mud as it passes through the outlet

tube (the Shear Rate) to the amount of force - the weight of the mud itself - that is causing the

mud to flow (the Shear Stress). Marsh Funnel Viscosity is reported as the number of seconds

required for one quart of mud to flow out of a full Marsh Funnel.

 

one set including a cup, a funnel and a balance.