Brookfield Dial Viscometer User Manual
Page 15
Brookfield Engineering Laboratories, Inc.
Page 15
Manual No. M/85-150-P700
The ratio of (
ω
r
) and (
c
) is a constant for any value of (
r
). Since (
c
) is a maximum at cone radius
(
r
), the shear rate is related to (
ω
) and sin
θ
.
For the Wells-Brookfield Cone/Plate Viscometer, the mathematical relationships are:
Shear Stress (dynes/cm
2
) =
T
2/3
π
r
3
Shear Rate (sec
-1
) =
ω
Sin
θ
Viscosity (centipoise or mPa•s) =
Shear Stress x 100
Shear Rate
where:
T = % Full Scale Torque (dyne-cm)
r
= Cone Radius (cm)
ω
= Cone Speed (rad/sec)
θ
= Cone Angle (degrees)
Angle
Radius
Cone Spindle
(deg.)
(cm)
CP-40 or CPE-40
0.8
2.4
CP-41 or CPE-41
3.0
2.4
CP-42 or CPE-42
1.565
2.4
CP-51 or CPE-51
1.565
1.2
CP-52 or CPE-52
3.0
1.2
Viscometer
Spring Torque
Model Series
(Dyne-Centimeter)
LV
673.7
RV
7,187.0
HA
14,374.0
HB
57,496.0