Brookfield DV1 Viscometer - Manual (Page 27)

Brookfield Engineering Laboratories, Inc. Page 27 Manual No. M14-023
The LV (1-4) and RV (1-7) spindles are designed to be used with the guardleg attached.
Measurements made without the guardleg will provide repeatable results but may not
provide “true” results.
When comparing data with others, be sure to specify the sample container and
presence/absence of the guardleg.
Many samples must be controlled to a specific temperature for viscosity measurement.
When conditioning a sample for temperature, be sure to temperature control the container
and spindle as well as the sample.
Please see our publication, “More Solutions to Sticky Problems”, for more details relating
to sample preparation.
III.3 Selecting a Spindle/Speed
The DV1 has the capability of measuring viscosity over a wide range (for example, the DV1MRV
can measure fluids within the range of 100-13,000,000 cP) (see Appendix B). This range is achieved
through the use of several spindles over many speeds.
The process of selecting a spindle and speed for an unknown fluid is normally trial and error. An
appropriate selection will result in measurements between 10-100 on the instrument % torque
scale. Two general rules will help in the trial and error process.
1. Viscosity range is inversely proportional to the size of the spindle.
2. Viscosity range is inversely proportional to the rotational speed.
In other words: to measure high viscosity, choose a small spindle and/or a slow speed. If the chosen
spindle/speed results in a reading above 100%, then reduce the speed or choose a smaller spindle.
Experimentation may reveal that several spindle/speed combinations will produce satisfactory
results between 10-100%. When this circumstance occurs, any of the spindles may be selected.
Non-Newtonian fluid behavior can result in the measured viscosity changing if the spindle and/
or speed is changed. See our publication, “More Solutions to Sticky Problems,” for more detail.
When viscosity data must be compared, be sure to use the same test methodology: the same
instrument, spindle, speed, container, temperature and test time.
III.4 Running a Test
A viscosity test is started by pressing the Motor On key while viewing the Home Screen (Section
II.2 ). Live measurement data will be displayed during the test. When the end criteria is met, the
final data will be displayed on the DV1 until the user presses a key. The following procedure outlines
the general steps necessary for making a viscosity measurement in a 600mL low form Griffin beaker
using the standard LV/RV/HA/HB spindles (61-64, 2-7).
1. Level the DV1 Viscometer, remove any attached spindles, and perform Autozero.
2. Prepare the sample to be tested and transfer to the 600mL low form Griffin beaker.