Brookfield DV-E Viscometer - Manual (Page 28)

Brookfield Engineering Labs., Inc. Page 28 Manual No. M98-350-J0912
3) Attach the tube to the mounting channel.
4) Lower the tube into the water bath reservoir, or if using the ULA-40Y water jacket, connect
the inlet/outlets to the bath external circulating pump.
5) Allow 30 minutes for the viscosity standard, sample chamber and spindle to reach test
temperature.
6) 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 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-E 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 or for one minute, whichever is
greater before the 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). However, instrument accuracy is ±2% of the
maximum viscosity range and not the standard 1%.
Interpretation of Calibration Test Results:
When verifying the calibration of the DV-E, the instrument and viscosity standard fluid error
must be combined to calculate the total allowable error.
The DV-E
is accurate to ( + /-) 1% of any full scale spindle/speed viscosity range.
Brookfield Viscosity Standards Fluids are accurate to ( + /-) 1% of their stated value.
EXAMPLE 1: Calculate the acceptable range of viscosity using RVDV-E with RV-3 Spindle
at 2 RPM; Brookfield Standard Fluid 12,500 with a viscosity of 12,257 cP at
25°C: