OfiTE 900, Instruction Manual, Page: 6 / 58

Patent No. 6,766,028 - OFI Testing Equipment, Inc.
OFITE, 11302 Steeplecrest Dr., Houston, TX 77065 USA / Tel: 832-320-7300 / Fax: 713-880-9886 / www.ofite.com
5
Shear Rate Range R1B1 R1B2 R1B3 R1B4 R1B5
Shear Rate Constant, K
R
,
(sec
-1
per RPM)
1.7023 0.3770 0.2682 0.2682 0.8503
Shear Rate, (sec
-1
or 1/s)
1 RPM
1.70 0.38 0.27 0.27 0.85
2 RPM 3.40 0.75 0.54 0.54 1.70
3 RPM 5.11 1.13 0.80 0.80 2.56
6 RPM 10.21 2.26 1.61 1.61 5.11
10 RPM 17.02 3.77 2.68 2.68 8.51
20 RPM 34.05 7.54 5.36 5.36 17.03
30 RPM 51.07 11.31 8.05 8.05 25.54
60 RPM 102.14 22.62 16.09 16.09 51.07
100 RPM 170.23 37.70 26.82 26.82 85.12
200 RPM 340.46 75.40 53.64 53.64 170.23
300 RPM 510.69 113.10 80.46 80.46 255.35
600 RPM 1,021.38 226.20 160.92 160.92 510.69
1,000 RPM 1,702.30 377.00 268.20 268.20 851.15
Viscosity Ranges
<a>
(cP)
R1B1 R1B2 R1B3 R1B4 R1B5
Minimum Viscosity
<b>
@600 RPM
0.5
<c>
4.5 12.7 25 1.2
Maximum Viscosity
<d>
@0.01 RPM
10,000,000 89,000,000 255,000,000 500,000,000 23,000,000
<a> Computed for standard Torsion Spring (F 1.0). For other torsion 160.92springs, multiply by F factor
<b> Lower viscosities can be measured by the Model 900, however one must take into account the
effect of bearing drag, Taylor vortices, zero offset, etc. when looking at the expected accuracy of
the reading
<c> For practical purposes the minimum viscosity is limited to 0.5 cP due to Taylor Vortices
<d> Maximum viscosity is based on Maximum Shear Stress and Minimum shear rate (RPM). However,
due to practical and physical limitations, it may be difficult to take these measurements.
Viscosity Conversions
To convert from units on left side to units on top, multiply by factor @ intercept.
Centipoise
(cP)
Poise (P) g/(cm*s) (mN*s)m
2
mPa*s
(lb*s)
100 ft
2
Centipoise
(cP)
1 0.01 0.01 1 1 0.002088
Poise (P) 100 1 100 100 100 0.2088
g/(cm*s) 100 1 100 100 100 0.2088
(mN*s)m
2
1 0.01 0.01 1 1 0.002088
mPa*s 1 0.01 0.01 1 1 0.002088
(lb*s)
100 ft
2
478.93 4.789 4.789 478.93 478.93 1