ALTANA Z7, Z10 User Manual

Measure what you see.

A5-A1 / A-T / U-Z6 / Z7-Z10

Bubble Viscometers

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Additives & Instruments

Bubble Viscometers
A5-A1 / A-T /
U-Z6 / Z7-Z10

Manual

English

PV-0500 Series
PV-0600 Series

BYK - Gardner USA

9104 Guilford Road
Columbia, MD 21046
USA
Phone [phone]
301-483-6500
Fax [phone]
301-483-6555

www.byk.com/instruments

BYK-Gardner GmbH

Lausitzer Str. 8
D-82538 Geretsried
Germany
Tel. 0-800-gardner
(0-800-4273637)
[phone]
Fax [phone]

Directions for Using the Gardner Bubble Viscometer

DIRECTIONS FOR USING THE
GARDNER BUBBLE VISCOMETER A-5 to A-1
CAT. NO. PV-0500

This instrument is based on the principle that the
viscosity is directly proportional to the bubble
speed. The viscosity of a sample of varnish or
other transparent liquid is therefore determined
by reference to the standard tubes in which an air
bubble rises with the same speed as it does in a
tube of the sample being tested. For this purpose
two carefully calibrated empty tubes are furnished
with each set.

The bubble size of the sample is rst adjusted as

nearly as possible to that in the standard tubes.
The tubes are then brought to a temperature of
25ºC (77ºF). This is essential due to the difference

in the temperature coefcient of viscosity of

mineral oils and varnishes. It is suggested that
a water bath be used, which quickly brings the
tubes to the proper temperature and insures
greater accuracy.

The bubble should be started from the at end

of the tube held in a true vertical position. The
bottom meniscus of the bubble should be used
for comparing the samples. It is only necessary
that they start together. Owing to unavoidable
differences in bubble sizes and in the shapes of
the ends of the tubes, it may be necessary to raise
one of the tubes so that the points of comparison
will be on the same level. The observation is made
after the bubbles are completely formes and
moving upwards along a true vertical line. This
takes place about 1½ to 2 cm from the bottom of
the tube.

The standard empty grade “A” tubes have been
carefully selected to and I.D. of 10.65 ± 0.0025
mm. and should be used for exact determinations.
However, this close tolerance is relatively
expensive, and for the sake of economy, tubes

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Directions for Using the Gardner Bubble Viscometer

having the same approximate diameter with a
tolerance of ± 0.150 mm. Grade “B” are used by
many manufacturer for general factory control
tests.

This viscometer meets the requirements of ASTM
D 154, D 555, D 1131, D 1545, D 1725, FTMS
14la-Method 4271, and AOCS Method Ka6.

Approximate Viscosity in Stokes at 25º C (77º F)

A5 0.051

A4 0.071

A3 0.140

A2 0.213

A1 0.310

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