Everything You Need To Know About Viscometers & Rheometers

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Everything from liquids to solids flows in a certain way and affects our daily lives: from the paint to the toothpaste you squeeze out of its tube.

Flow and deformation behaviour are important parameters when it comes to material characterization. Viscometers and rheometers are the ideal instruments to see whether your specimen is in the right flow.

Whether to buy either a viscometer or a rheometer is not always straightforward. This blog will take you through the differences and how a rheometer could suit your needs.

What Is Viscometer?

A device used to measure liquids’ fluid viscosity and flow properties is known as a viscometer. Viscosity is the unit measure of a fluid’s resistance to shear stress or flow at a given temperature. Viscometers only measure under one flow condition.

Either the object is fixed, and the fluid moves past it, or the fluid remains stationary, and an object moves through it. The drag caused by the relative motion of the fluid and surface is a measure of viscosity. The flow condition must have an adequately small value of Reynolds number for there to be laminar flow.

Types Of Viscometer

  • Rotational viscometer
  • Vibrational viscometer
  • Falling piston viscometer
  • Oscillation viscometer
  • Falling sphere viscometer
  • Capillary tube viscometer
  • Saybolt viscometer
  • Redwood viscometer
  • Orifice type viscometer etc

Applications Of Viscometer

  • Measuring the flow of engine oil under various temperature conditions.
  • Studying the viscosity of jams and syrups to confirm batch consistency.
  • Examining the flow properties of milk to develop suitable piping systems. 

Things You Need To Know About Viscometer

  • The viscometer is a device used to calculate fluid viscosity and the flow properties of liquids.
  • There are several distinct viscometer types: rotational viscometer, oscillation viscometer, vibrational viscometer, falling sphere viscometer, saybolt viscometer, falling piston viscometer, redwood viscometer, capillary tube viscometer, orifice type viscometer, etc.
  • Viscometers can only measure the viscosity of liquids.
  • The viscometer is used to calculate those fluids, which a single viscosity value can define.
  • Viscometers calculate viscosity over a limited shear rate range.
  • The viscometer isn’t capable of working as a Rheometer.
  • Viscometers can just measure the viscosity of the fluid under specific conditions, i.e., a liquid that follows Newton’s law of viscosity.
  • Viscometers are widely used in industries to monitor batch consistency and quality control.

What Is Rheometer?

A Rheometer is a laboratory device that is used to measure how a liquid, slurry, or suspension flows in response to applied forces. It is used for those liquids which cannot be determined by a single value of viscosity and hence require more parameters to be set and measured.

Types Of Rheometer

  • Capillary Rheometer
  • Extensional Rheometer
  • Torque Rheometer
  • Interface Rheometer

Applications Of Rheometer

Rheometers have comprehensive and mixed applications in the material science and chemical industries for things such as oil, plastics, asphalt, wax, paints, coatings, and adhesives. They are also used for food, beverages, and personal-care products such as cosmetics, shampoo, and toothpaste.

Things You Need To Know About Rheometer

  • Rheometers are equipment that is used to decide the rheological properties of polymer solutions, polymer melts, coatings, suspensions, emulsions, inks, and foods.
  • Types of Rheometers include capillary rheometer, rotary rheometer, extensional rheometer, torque rheometer, and interface rheometer.
  • A rheometer can measure rheological properties, fluid’s internal flow resistance, and flow properties of liquids.
  • A rheometer is used for the fluids that cannot be described by a single value of viscosity and thus require more parameters to be set and measured.
  • A Rheometer can also work as a viscometer.
  • Rheometers measure viscosity over a broad shear rate range.
  • A Rheometer can calculate the properties of fluids under any condition, i.e., whether a fluid follows or does not follow Newton’s law of viscosity. Fluids that follow Newton’s law of viscosity are called Newtonian Fluids, whereas the ones that don’t follow are referred to as Non-Newtonian fluids.
  • Rheometers are used in industries for quality control and to monitor batch consistency.

Which One Would Be The Perfect Choice For You?

A rheometer is a tool used to measure how a liquid flows in response to applied force, whereas a viscometer is a tool used to measure the viscosity of a fluid. The advanced versatility and performance make rheometers an excellent tool for research, product and process development, and quality control testing.

A rheometer will measure viscosity over a wide shear rate range, while a viscometer will measure viscosity over a limited range.


Now that you know the types, functions and benefits of both viscometers and rheometers, you can easily choose which one will be perfect for you.

Make sure you get good models like RV-10000A Tuning Fork Vibro Rheometer or SV-A Series Vibro Viscometers for trusted dealers across Australia like A&D weighing!

They have been weighing scales & balances for a long time and have a local team for service & calibration, and system design. 

Get the best viscometers and rheometers from A&D weighing today!