Description
A viscometer, viscosity meter or rheometer is a measuring instrument used to determine a fluid’s internal flow resistance or viscosity. The term viscosity typically refers to shear viscosity, i.e., how a material reacts to being sheared. Rotational viscometers with rotating spindles or rotors, also known as “cup and bob” or Searle viscometers, are the most common tools used to measure the shear viscosity of fluids. However, a fluid’s viscosity also may be measured on the basis of stretching. The technical term to refer to this is extensional viscosity.
A viscometer is frequently used in laboratories, but it also has practical applications in factories and other industrial environments. A viscometer can be an important component in process and quality control. Companies can save money by placing a viscometer in a production line and making fluid viscosity measurements in real time.
To determine the right viscometer for your application, consider the following factors:
– Viscosity range of your fluid (low, medium or high)
– Required rotational speeds or shear rates
– Size of the liquid sample to be tested
– Need for temperature measurement
– Nature of your fluid (Newtonian, non-Newtonian, dilatant, thixotropic, etc.)
– 1 millipascal-second (mPa.s) = 1 centipoise (cP)