Brookfield CAP2000 Viscometer - Manual (Page 18)

Brookfield Engineering Labs., Inc. Page 18 Manual No. M/94-310F
SAMPLE SIZE
It is necessary that sufficient sample is placed between the cone and plate to completely
cover the surface of the cone when the cone is locked in the RUN position. With sufficient
sample, an excess of about 1 mm in width will be seen around the periphery of the cone edge.
For calibration and best reproducibility of results, the sample sizes shown in Table A1
should be used.
CAP 2000 RANGES FOR CONES 01 THROUGH 06
To determine the full scale viscosity range (FSR) for any cone/speed, divide the Cone Range
Coefficient (refer to Table A3) by the rotational speed (RPM).
Full Scale Viscosity Range (poise) = Cone Range Coefficient Equation A1
RPM
CAP 2000 RANGES FOR CONES 07 THROUGH 99
Spindle Multiplier Constant (SMC):
SMC = (supplied by the manufacturer)
Shear Rate Constant (SRC):
SRC = (supplied by the manufacturer)
Viscosity (poise) = Shear Stress (dynes/cm 2 ) Equation A2
Shear Rate (sec -1 )
Shear Stress (dynes/cm 2 ) = Viscosity (poise) x Shear Rate (sec -1 ) Equation A3
Shear Rate =
ω
sin
θ
Equation A4
ω
= Cone Speed (rad/sec) =
( 2
π
60
)
x N
N = RPM
θ
= Cone Angle (degrees)
r = radius of cone spindle
Viscosity (poise) = Full Scale Viscosity Range x (% FSR) Equation A5
100