Typical Measurement Routine
RHEOTEK’s
Applications Team have worked hard to automate sample addition of high
viscosity samples. Low volume of sample and well engineered viscometer
design means that sample addition on the HVV-6 is simple and
straightforward using a pipette. Withdraw the Teflon plug, add the sample,
replace the plug and press start.
Automatic
Calculations, Results Database & LIMS
Following
a successful flow time measurement the HVV-6 software calculates the
Kinematic Viscosity. Results are printed and/or stored for review at a
later date. Results can also be exported automatically for use by a LIMS
system.
Automatic
“Safe-Vac” Cleaning
Once
the measurement is complete the HVV-6 automatically cleans and dries the
viscometer tube ready for another measurement. The RHEOTEK Applications
Team have worked hard to develop cleaning routines specifically for high
viscosity samples. Each stage is carefully controlled to clean all parts
of the viscometer tube. The HVV-6 minimizes solvent usage through
carefully controlled software parameters. Our aim is to completely remove
the sample from the capillary viscometer and associated tubing etc. This
means that the viscometer is clean and dry and there is NO CONTAMINATION for the next sample. The
viscometer is cleaned so very efficiently – it really has to be seen to
be believed. Cleaning is carried out under vacuum. We call this our Safe
Vac system - completely under vacuum in a sealed solvent system
– with no chance of solvent escaping. The cleaning is very effective and
is one reason why the accuracy of the HVV-6 is so good.
Thermostatic Stirred Liquid Bath
The
HVV-6 uses a stirred liquid bath to control the temperature of the sample
within +/- 0.005°C of the required temperature. The required temperature
set point can be programmed by the operator.
HVV-6
Viscometer Tubes
The
HVV-6 uses a dual bulb capillary viscometer, manufactured from
borosilicate glass. This means that each result is generated from two flow
times, in accordance with Test Methods.
Flow
time measurement
Viscometers
have fiber optics sensors mounted against the glass. This removable
mechanism means that viscometers can be replaced without the need to
discard the optics. Flow times are measured accurately within 0.01
seconds. The optical sensors are mounted outside the bath which allows
measurement temperatures up to 150 °C to be achieved.
