Cannon Instrument CMRV-4500 - Manual (Page 42)

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CANNON ® Mini-Rotary Viscometer CMRV-4500 Instruction & Operation Manual
Version 1.1e—October, 2011 • CANNON ® Instrument Company
2139 High Tech Road • State College, PA • 16803 • USA
η = viscosity of the calibration standard (cP)
t
3r
= time for 3 revolutions of the rotor (sec)
Cell calibration procedure
Calibration standards CANNON ® viscosity standard N105B is recommended for calibration at
-20°C and -25°C. This calibration is required for running ASTM profiles
included with the software. At -20°C, N105B has a nominal viscosity of
30,000 cP (mPa·s). At -25°C, N105B has a nominal viscosity of 56,600
cP (mPa·s).
It is also possible to calibrate the CMRV cells at -25°C using viscosity
standard
N400B with a nominal viscosity of 60,000 cP (mPa·s).
CANNON ® Instrument Company can furnish viscosity standards for a
variety of temperatures and viscosities. The CMRV-4500 can be cali-
brated over the viscosity range of 1 to 99,999 cP (mPa·s).
After you have prepared the CMRV-4500 for the calibration run (see
Chapter 6) follow the procedure below to calibrate the CMRV.
Preparing the cells
Introducing sample 1. Place 10 ml of the calibration
standard into each of the nine
cells (see photo).
2. Carefully place the rotors in
their corresponding viscomet-
ric cells, making sure that the
rotor tip at the bottom of the
shaft slides into the recess at
the bottom of the cup. Do
NOT drop the rotors into place.
3. Secure each rotor in position with a rotor pin, and make sure that the
rotor locking pin is in the raised position.
Winding rotors 4. To wind the rotors in preparation for the cell calibration, slide the
pulley-wheel assembly along the track until the pulley is aligned with
the rotor to be wound. Use the engraved lines on the slide bar as a
guide to determine the proper position of the left side of the pulley-
wheel block.
5. Place the loop of a thread over the left end of the crossbar at the top
of the rotor shaft.
6. Pass the free end of the thread (the end with the plastic ring) over the
pulley-wheel and allow it to hang freely in front of the viscometer.
While holding the rotor motionless, hook a light weight, such as a
large paper clip, on the plastic ring to apply slight tension to the
thread.
7. Guiding the thread with your finger, turn the rotor clockwise to wind
the thread above the crossbar until the knot in the loop has been
Injecting standard into CMRV test
cells