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Brookfield DV-III Ultra Rheometer User Manual

Page 118

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Brookfield Engineering Laboratories, Inc.

Page 118

Manual No. M/98-211-B0104

Brookfield Engineering Laboratories, Inc.

Page 118

Manual No. M98-211-E0912

Calibration Procedure using a Helipath Stand and T-Bar Spindles

When a Helipath Stand and T-Bar spindles are used:

Remove the T-bar spindle and select a standard LV(#1-3) or RV,HA,HB (#2-6) spindle. Follow the

procedures for LV(#1-3) and RV,HA,HB (#2-6) Brookfield spindles outlined above.

T-Bar spindles should not be used for verifying calibration of the DV-III Ultra Rheometer.

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-III Ultra 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 for a

minimum of 1 hour, stirring the fluid periodically (operate at 50 or 60 RPM periodically), prior

to taking measurements.

5) After 1 hour, check the temperature of the viscosity standard fluid with an accurate

thermometer.

6) If the fluid is at test temperature (

+

/- 0.1

°

C of the specified temperature, normally 25

°

C),

measure the viscosity and record the viscometer reading.

Note:

The spindle must rotate at least five (5) times for one minute, whichever

is greater before readings are taken.

7) The viscosity reading should equal the cP value on the viscosity fluid standard to within the

combined accuracies of the viscometer and the standard (as discussed in the section entitled,

Interpretation of Calibration Test Results).

Calibration Procedure for Cone/Plate Viscometers:

1) Follow the gap setting procedures in Appendix A for mechanically adjusting the setting of the

cone spindle to the plate.

2) Refer to Appendix A, Table A-1, and determine the correct sample volume required for the

selected spindle.

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. Consult with Brookfield

or an authorized dealer to determine which fluid is appropriate.

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-III 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 Rheometer reading should

be 97% torque and 9.7 cP viscosity ± 0.197 cP (0.1 cP for the rheometer plus 0.97 cP for the

fluid). The accuracy is a combination of Rheometer and fluid tolerance (refer to Interpretation

of Calibration Test Results).

4) With the viscometer stopped, remove the sample cup and place the viscosity standard fluid into

the cup, waiting 10 minutes for temperature equilibrium.