Brookfield DV-I Viscometer - Manual (Page 36)

Brookfield Engineering Laboratories, Inc. Page 36 Manual No. M/92-021-O604
Calibration Procedure for a Helipath Stand and T-Bar Spindles
T-Bar spindles should not be used for verifying calibration of the DV-I+ Viscometer.
When a Helipath Stand and T-Bar spindles are used:
Remove the T-bar spindle and select a standard LV(#1-4) or RV,HA,HB(#1-7) spindle. Follow
the procedures for LV(#1-4) and RV,HA,HB (#1-7) Brookfield spindles outlined above.
Calibration Procedure for Spiral Adapter
1) Place the viscosity standard fluid (in the proper container) into the water bath.
2) Attach the spindle to the viscometer. Attach chamber (SA-1Y) and clamp to the
viscometer.
3) Lower the DV-I+ into measurement position. Operate the viscometer at 50 or 60 RPM until
the chamber is fully flooded.
4) The viscosity standard fluid, together with the spindle, should be immersed in the bath.
Stirring the fluid periodically (operate at 50 or 60 RPM), prior to taking measurements to
encourage temperature equilibrium.
NOTE: The spindle must rotate at least five (5) times or for one minute, whichever is
greater before readings are taken.
5) Measure viscosity and record the viscometer reading; include % and cP (m•Pas).
Calibration Procedure for Cone/Plate Viscometers:
1) Follow the procedures outlined in Appendix A for mechanically adjusting the setting of
the cone to the plate.
2) Refer to Appendix A, Table 1, and determine the correct sample volume required for the
spindle to be utilized.
3) Select a viscosity standard fluid that will give viscosity readings between 10% and 100%
of full scale range. Refer to Appendix B for viscosity ranges of cone spindles. Do not use
a silicone viscosity standard fluid with a viscosity value greater than 5000 cP with a Cone/
Plate Viscometer. Brookfield offers a complete range of mineral oil viscosity standards
suitable for use with Cone/Plate Viscometers. See Table E-2. It is best to use a viscosity
standard fluid that will be close to the maximum viscosity for a given cone spindle/speed
combination.
Example: LVDV-I+ Viscometer, Cone CP-42, Fluid 10
Having a viscosity of 9.7 cP at 25
°
C
At 60 RPM, the full scale viscosity range is 10.0 cP. Thus, the Viscometer reading should
be 97% torque and 9.7 cP viscosity
±
0.197 (closer to
±
0.2) cP. The accuracy is a
combination of Viscometer and fluid tolerance (refer to Interpretation of Calibration
Test Results).