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3.3 Preparation of the sample
If the samples to be measured (measuring liquids) may contain particles, they must be filtered prior to
being introduced into the viscometer.
For low viscosity liquids, the following filters are recommended
a) Low-viscosity liquids:
•
Glass filter, e.g. Duran
•
Syringe adapter filters (laboratory suppliers) that are used in combination with disposable syringes
with Luer connections. A pore width of approx. 5 µm is suitable for use in capillary viscometry.
When selecting suitable filters, you must pay attention to the chemical resistance against the
samples to be measured.
Syringe adapter filters are intended for use by pushing; i.e. the sample is filtered from the
syringe through the filter. If this is not performed correctly, there is a risk of the syringe filter
detaching itself from the syringe due to the created pressure and of the sample being
spilled! Therefore, you should use syringes with Luer lock connections that are fixed to the
syringe filters. Hazardous liquids should not be filtered by pushing through the filter holder for
safety reasons.
•
Especially for aggressive or toxic liquids used in polymer analytics, SI Analytics
system ProCleanII (VZ 7090), where the sample is filtered by suction through a small filtering
plate. Here, there is no risk of spilling during filtering.
b) High-viscosity liquids:
•
Sieve with 0.3 mm mesh size
Fill the measuring liquid through the fill tube (21) into the reservoir vessel (27).
Also see the respective operating manualof the viscometer.
®
porosity 2 to 4 (10...100 µm)
®
offers the filtering