Viscosity Measurement – An Overview
Viscosity Measurement – It is fair to say that if you are concerned with viscosity measurement, that you probably already understand the concept of viscosity in the first place. However, a less experienced technician might be surprised by the range of factors involved in measuring viscosity.
Before we start, it is important to decide what we are attempting to measure. We might seek to measure the dynamic viscosity – often simply referred to as the viscosity – or we may be more interested in the kinematic viscosity, which factors in the density of the fluid being measured.
Additionally, not all fluids act in the same manner. For instance, Newtonian fluids will behave differently from Non-Newtonian fluids. To clarify – Newtonian fluids maintain a constant viscosity regardless of the shear rates being applied. However, for Non-Newtonian fluids, there is no constant viscosity, and the process of measuring requires greater regulation of environmental conditions such as temperature.
Viscosity measurement – Four Generations of the Laboratory Viscometer – The NuLine (L), the original ICI (2nd L) and the intermediate models that followed.
Viscosity Measurement in a Laboratory setting
The equipment used in viscosity measurement – unsurprisingly known as a viscometer – needs to generate a relative motion of a fluid against a solid object. It doesn’t matter whether the fluid or the solid object are in motion, just so long as drag is induced. Typically, this motion can be generated using suction, gravity, oscillation, vibration, or rotation, to name just a few methods. In a laboratory setting, a particularly accurate and reliable method of viscosity measurement is the Cone & Plate Viscometer.
These portable viscometers can measure the drag induced by a spinning cone in contact with the fluid being investigated. A sample of the fluid is placed upon the temperature-controlled plate, and a shallow cone is lowered down onto the fluid. With all the necessary parameters set, the cone is rotated, and the resistance caused by the fluid is measured. The viscometer calculates the viscosity, which is digitally displayed on the screen, or sent directly to a PC for recording.
The NuLine Cone & Plate in action (L) and its digital display (R)
The NuLine Cone & Plate Viscometer
ATAC manufactures an excellent version of a Cone & Plate Viscometer. Originally designed by ICI Paints, and then developed by REL, it has been refined over time to become a highly accurate and reliable solution to viscosity measurement in a laboratory setting. This benchtop viscometer is fully portable and provides for at-line measurement wherever it is required.
There are two variants on offer – depending on the temperature range required. Other options include the button type, plate finish, and display language. The latest model – the NuLine Viscometer – is already establishing itself as a market-leader, combining the highest application of engineering excellence with a competitive price tag.
For more information about the NuLine Cone & Plate Viscometer, give our team of experts a call, or click on the link below to read more on our laboratory viscometer product page. They can talk you through the specifications that fit your requirements, and ensure that everything is taken care of. Email us today at sales@atacgroup.com or give us a call on +44 (0)1380 818411.
Did you know we also manufacture Process Viscometers & PPA?
Feature Photograph courtesy of Pawel Czerwinski
