Cannon Instrument CMRV-5000 - Manual (Page 71)

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CANNON ® Mini-Rotary Viscometer CMRV-5000 Instruction & Operation Manual
Version 1.0b—August, 2011; CANNON ® Instrument Company
2139 High Tech Road • State College, PA • 16803 • USA
CHAPTER
12
MEASURING YIELD STRESS AND
VISCOSITY
NOTE The guidelines in this section are not intended to supercede any test
method. Always refer to the method for validation of any test procedure.
Yield Stress and Viscosity testing should take place shortly after the
profile is completed.
NOTE ASTM D 4684 requires completion of yield stress and viscosity tests
within 30 minutes of the conclusion of the profile.
When the CMRV-5000 has reached the final test temperature, the Instru-
ment View window will display the Ready for Test/Instrument Ready
status.
The (yield stress) and (viscosity) icons for each sample
will also be enabled.
NOTE The yield stress test must be completed BEFORE testing for viscosity.
To view test results as they are recorded in the VISCPRO database, open
and/or configure the appropriate analysis (see the next chapter on Analyses
for more information) prior to beginning the tests.
Measuring yield stress
Procedure
1. Remove the Plexiglas ® cover from the CMRV-5000 unit.
2. Slide the pulley-wheel assembly along the track until the pulley is
aligned with the left side of the shaft of the appropriate rotor. Use the
engraved lines on the slide track to determine the proper position of
pulley wheel block relative to the rotor.
3. Make sure that the pulley-wheel sensor wire is placed in a position to
prevent its interference with the falling hook-cage/weight during
yield stress/viscosity testing.
4. Place the rotor thread over the pulley-wheel with the plastic disk
hanging in front of the viscometer block and over the edge of the
table.
5. Hang the hook-cage on the ring at the end of the thread.
NOTE ASTM D 3829 and 4684 specify an initial weight of 10-grams, and
increase of weight in 10-gram increments. ASTM D 6821 specifies an
initial weight of 2.5 grams and increase of weight in 2.5-gram increments.