Viscosity Analyzers (Non‐ ASTM )

Viscosity is a property that determines a fluid's rate of flow. Process viscometers typically measure the fluid viscosity by one (or a combination) of two methods: exposing a constant-area moving surface to a constant thickness of fluid and measuring the forces that resist the movement of the surface; or exposing a constantly moving thickness of fluid to a fixed surface and measuring the forces that resist the fluid flow. Rotational viscometers are based on the principle of sensing the viscous drag imposed on a cylinder or disk rotated at a constant speed or, in a variation, sensing the drag torque applied to a stationary element when a cylinder or disk is rotated in its presence. Most glass capillary viscometers are limited to the measurement of Newtonian fluids with low viscosities. Most rheometers are similar in concept to the viscometers.