Brookfield Dial Viscometer - Manual (Page 3)

Brookfield Engineering Laboratories, Inc. Page 3 Manual No. M/85-150-P700
I. INTRODUCTION
The Brookfield Dial Viscometer measures fluid viscosity at given shear rates. Viscosity is a measure
of a fluid’s resistance to flow. You will find a detailed description of the mathematics of viscosity
in the Brookfield publication “More Solutions to Sticky Problems” a copy of which was included
with your Dial Viscometer. The Dial Viscometer rotates a sensing element in a fluid and measures
the torque necessary to overcome the viscous resistance to the induced movement. This is
accomplished by driving the immersed element, which is called a spindle, through a beryllium copper
spring. The degree to which the spring is wound, indicated by the red pointer, is proportional to the
viscosity of the fluid.
The Viscometer is able to measure over a number of ranges since, for a given spring deflection, the
actual viscosity is proportional to the spindle speed and is related to the spindle's size and shape. For
a material of given viscosity, the resistance will be greater as the spindle size and/or rotational speed
increase. The minimum viscosity range is obtained by using the largest spindle at the highest speed;
the maximum range by using the smallest spindle at the slowest speed.
There are four basic spring torque series offered by Brookfield:
Model Spring Torque (Dyne-cm)
LV 673.7
RV 7,187.0
HA 14,374.0
HB 57,496.0
The higher the torque calibration, the higher the measurement range. The viscosity measurement
range for each torque calibration may be found in Appendix B.
All units of measurement are calculated in units of centipoise (cP) by using a look-up table
known as "the Brookfield Factor Finder" to convert torque reading. The equivalent units of
measurement in the SI system are calculated using the following conversions:
CGS SI
Viscosity: 1 cP = 1 mPa•s mPa•s = milli Pascal - second
Torque: 107 dyne-cm = 1 Newton-m
I.1 Components
1) Dial Viscometer
2) Model A Laboratory Stand
3) Spindle Set with Case (4 spindles for LVF, LVT; 7 Spindles for RVF, RVT, HAT, and HBT).
For Cone/Plate versions: a spindle wrench, one cone spindle and a sample cup (Part No.
CP-44Y) replace the spindle set
4) Guard Leg (LVF, LVT, RVF, and RVT only)
5) Carrying Case
6) Operating Instruction Manual
7) Factor Finder
Please check to be sure that you have received all components, and that there is no damage. If you
are missing any parts, please notify Brookfield Engineering or your local Brookfield agent immedi-
ately. Any shipping damage must be reported to the carrier.