Brookfield YR-1 Rheometer - Manual (Page 6)

Brookfield Engineering Labs., Inc. Page 6 Manual No. M02-215-B0412
spindle. The maximum torque value is the yield point. The straight line in Figure I-3 is a repeat
of what was shown in Figure I-2. An algorithm in the YR-1 firmware converts the maximum
torque value into a yield stress value.
The shear stress measurement range of the YR-1 (in Pascals) is determined by the size and shape
of the vane spindle, and the full scale torque range of the calibrated spring.
There are four basic spring torque series offered by Brookfield:
Spring Torque
Model dyne-cm milli Newton - m
1/4RVYR-1 1,796 0.1796
RVYR-1 7,187 0.7187
HBYR-1 57,496 5.7496
5XHBYR-1 287,480 28.7480
The shear stress measurement range for the three standard (or supplied) vane spindles at each
spring torque is as follows:
SPINDLE TORQUE RANGE
SHEAR STRESS
RANGE (Pa)
V-71 1/4 RV .125-1.25
V-72 1/4 RV .5-5
V-73 1/4 RV 2.5-25
V-71 RV .5-5
V-72 RV 2-20
V-73 RV 10-100
V-71 HB 4-40
V-72 HB 16-160
V-73 HB 80-800
V-71 5xHB 20-200
V-72 5xHB 80-800
V-73 5xHB 400-4000
Table I-1
The equivalent units of measurement in the SI system are calculated using the following con-
versions:
SI CGS
Shear Stress: 1 Pascal or 1 Newton/m 2 = 10 dyne/cm 2
Torque: 1 Newton-m = 10 7 dyne-cm