M19-354
Page 12
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2019 AMETEK Brookfield Inc. All rights reserved.
not be filled more than half way with the sample in order to minimize pressure build-up due
to the air bubbles. Due to the design of the upper locking plug, air bubbles cannot get into
the sample tube.
• The sample must be free of air bubbles between the two locking plugs. The lid of the upper
locking plug is attached and the temperature control (desired test temperature) must be
achieved.
After proper temperature control is achieved, the upper cap is screwed on.
Do not heat the sample with the upper lid attached as pressure may build in the tube.
NOTE: Gas bubbles can be removed by warming up the sample for a short time (approximately
20 degrees above the measuring temperature with the upper locking plug removed)
or by lightly tapping on the lid of the upper locking plug.
II.3 Temperature Control of the Sample
The following are suggested working fluids for the circulating temperature bath:
Temperature
Range
Bath Working Fluids
Tubing
-5 to +20
°
C
Water (distilled) - glycol-mixture; mixed
in accordance with the manufacturer’s
instructions for the temperature range
Insulated Latex tubing,
secured with tube band clips
+1
°
C to +80
°
C
Distilled water
Latex tube
+80
°
C to +150
°
C
Transparent thermostatic oil
Insulated Fluran tube,
secured with tube band clips
The inlet and outlet ports should be oriented in the following manner. During initial fill of
water jacket, the inlet will be at the bottom of the viscometer and the outlet will be at the top.
The tubing from the circulating bath should be pushed tightly onto the viscometer tubes. By
pulling gently, check whether the tubing is firmly attached. Tubing and circulating baths are
available on request from AMETEK Brookfield or your local authorized dealer. If the water
bath jacket has condensation on the glass, rub with alcohol.
The sample tube is sealed with the upper cap after temperature set point has been achieved.
Allow 30 minutes for thermal equilibrium.
Falling ball viscometers provide precise temperature control for the sample. By measuring
your sample at multiple temperatures, you can determine the temperature viscosity curve.
