High Shear Cylinder Sensor System Hs - Thermo Scientific HAAKE RotoVisco 1 Instruction Manual

Sensor Systems

12.11 High Shear Cylinder Sensor System HS

Application:
The sensor system HS is primarily used for viscosity mea-
surements at high shear rates e.g. for coating materials,
PVC--plastisols, oils etc. It can, furthermore, be used to de-
termine the shear stability of emulsions which tend to split or
R
a
slip "on the rotor" or "in the gap". The coaxial cylinder sensor
R
system consists of a beaker with a temperature jacket and
i
two rotors covering different measuring ranges.
The temperature vessel is not required in this case.
The beaker is hooked up to the measuring system. The ro-
tors are inserted from below. A double universal joint
achieves self--centering of the rotor in the cup.
The test substance is injected by means of a syringe until it
appears at the upper rim of the annual gap. Highly viscous
substances are loaded by means of small grease gun.
If the test substance is non--thixotropic, a rotational speed
.
γ
with small is applied while injecting the substance. This will
support charging and rotor centering.
Measurements at high speeds will cause considerable
amounts of heat in the annular gap. It is, therefore, important
that a circulator with a high pumping capacity and short con-
necting hoses is selected. In most cases this enables mea-
surements without temperature drift due to frictional heating.
Should this not be possible, it is recommended to conduct a
step--by--step or a rapid automatic flow curve measurement.
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