Owner manual

Brookfield Engineering Laboratories, Inc. Page 19 Manual No. M/98-211-A0701
III. MAKING VISCOSITY MEASUREMENTS
III.1 Quick Start
The DV-III+ Rheometer uses the same methodology as the Brookfield Dial Reading Viscometer
and DV series of Digital Viscometers. If you have experience with other Brookfield equipment, this
section will give you the quick steps for taking a viscosity reading. If you have not used a Brookfield
Viscometer before, skip this section and go to Section III.2 for a detailed description.
A) Assemble and level the rheometer (Section I.5).
B) Autozero the rheometer (Section II.1).
C) Enter the spindle number using the SELECT SPINDLE key (Section II.3).
D) Introduce the spindle into the sample and attach the spindle to the coupling nut.
NOTE: Left-hand threads.
E) Enter the speed of rotation using the number pad and ENTER key (Section 11.4).
F) Record % torque and viscosity.
III.2 Preparation
A) RHEOMETER: The DV-III+ should be turned on, leveled and autozeroed. The level is
adjusted using the three feet on the bottom of the base and confirmed using the bubble on the
top of the head. Adjust the feet until bubble is inside the center target. Set the level prior to
autozero and check the level prior to each measurement.
Proper level is essential for correct operation of the DV-III+.
B) SAMPLE: The fluid to be measured (sample) must be in some container. Many spindle systems
from Brookfield are supplied with specific sample chambers such as the Small Sample Adapter,
UL Adapter and Thermosel. The standard spindles supplied with the DV-III+, LV (1-4), RV
(1-7) and HA/HB (1-7), are designed to be used with a 600ml low form Griffin beaker (or
equivalent container with a diameter of 8.25 cm).
Brookfield recommends that you use the appropriate container for the selected spindle. You
may choose to use an alternate container for convenience, however, this may have an effect on
the measured viscosity. The DV-III+ is calibrated considering the specified container.
Alternate containers will provide results that are repeatable but not "true."
The LV (1-4) and RV (1-7) 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 detail relating to
sample preparation.