Brookfield DV-II+ Digital Viscometer - Manual (Page 35)

- 35 -
Brookfield Viscosity Standard Fluids are reusable provided they are not contaminated. Normal
practice for usage in a 600 ml beaker is to return the material from the beaker back into the bottle.
When using smaller volumes in accessories such as Small Sample Adapter, UL Adapter or
Thermosel, the fluid is normally discarded.
Calibration Procedure for LV(#1-4) and RV,HA,HB(#1-7) Brookfield Spindles
1) Place the viscosity standard fluid (in the proper container) into the water bath.
2) Lower the DV-II+ into measurement position (with guard leg if LV or RV series Viscometer
is used).
3) Attach the spindle to the Viscometer. If you are using a disk-shaped spindle, avoid trapping air
bubbles beneath the disk by first immersing the spindle at an angle, and then connecting it to the
Viscometer.
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, 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 before readings are taken.
7) The viscosity reading should equal the cP value on the fluid standard to within the combined
accuracies of the Viscometer and the viscosity standard (as discussed in the section entitled,
Interpretation of Calibration Test Results, page 37).
Calibration Procedure for a Small Sample Adapter
When a Small Sample Adapter is used, the water jacket is connected to the water bath and the water is
stabilized at the proper temperature:
1) Put the proper amount of viscosity standard fluid into the sample chamber. The amount varies
with each spindle/chamber combination. (Refer to the Small Sample Adapter instruction
manual).
2) Place the sample chamber into the water jacket.
3) Put the spindle into the test fluid and attach the extension link, coupling nut and free hanging
spindle (or directly attach the solid shaft spindle) to the DV-II+.
4) Allow 30 minutes for the viscosity standard, sample chamber and spindle to reach test
temperature.
5) Measure the viscosity and record the Viscometer reading.
Note: The spindle must rotate at least five (5) times before a viscosity reading is taken.
Calibration Procedure for a Thermosel System
When a Thermosel System is used, the controller stabilizes the Thermo Container at the test temperature.