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8130-5
STANDARD
First edition
1992-I 2-15
Coating powders -
Part 5:
Determination of flow properties of a powder/air
mixture
Poudres pour revt%ement -
Partie 5: LMermination de /‘aptitude ZI la fluidisation d’un melange
poudreiair
--
Reference number
IS0 8130-5: 1992(E)
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IS0 8130=5:1992(E)
Foreword
IS0 (the International Organization for Standardization) is a worldwide
federation of national standards bodies (IS0 member bodies). The work
of preparing International Standards is normally carried out through IS0
technical committees. Each member body interested in a subject for
which a technical committee has been established has the right to be
represented on that committee. International organizations, govern-
mental and non-governmental, in liaison with ISO, also take part in the
work. IS0 collaborates closely with the International Electrotechnical
Commission (IEC) on all matters of electrotechnical standardization.
Draft International Standards adopted by the technical committees are
circulated to the member bodies for voting. Publication as an lnter-
national Standard requires approval by at least 75 % of the member
bodies casting a vote.
International Standard IS0 8130-5 was prepared by Technical Committee
ISO/TC 35, Paints and varnishes, Sub-Committee SC 9, General test
methods for paints and varnishes.
IS0 8130 consists of the following parts, under the general title Coating
powders:
- Part 1: Determination of particle size distribution by sieving
- Part 2: Determination of density by gas comparison pyknometer
(referee method)
liquid
- Part 3: Determination of density by displacement
pyknometer
- Part 4: Calculation of lower explosion limit
- Part 5: Determination of flow properties of a powder/air mixture
- Part 6: Determination of gel time of thermosetting coating powders
at a given temperature
- Part 7: Determination of loss of mass on stoving
- Part 8: Assessment of the storage stability of thermosetting pow-
ders
0 IS0 1992
All rights reserved. No part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without
permission in writing from the publisher.
International Organization for Standardization
Case Postale 56 l CH-1211 Geneve 20 l Switzerland
Printed in Switzerland
ii
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IS0 81304:1992(E)
- Part 9: Sampling
Annexes A and B of this part of IS0 8130 are for information only.
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INTERNATIONAL STANDARD IS0 8130-5:1992(E)
Coating powders
Part 5:
Determination of f ow properties of a powder/air mixture
tion of the standard indicated below. Members of
1 Scope
IEC and IS0 maintain registers of currently valid
International Standards.
This part of IS0 8130 specifies a method for deter-
mining the flow properties of a mixture of coating
IS0 8130.9:1992, Coating powders - Part 9: Sam-
powder and air. The method reflects commercial
pling.
practice in powder spraying (see “Bibliography”,
annex B).
The results obtained are influenced by the compo- 3 Principle
sition of the coating powder, its density, particle size
distribution and particle shape, together with the Under draught-free conditions, a specified quantity
tendency of the particles to agglomerate and to ac- of coating powder is placed in a vessel and is
cept a triboelectric charge. fluidized with clean dry air under standard condi-
tions of atmospheric temperature and pressure. The
NOTE 1 It is well known that the transport and spraying
height of the powder during and after fluidization is
characteristics of powders are highly dependent on their
measured and the rate at which the fluidized powder
flow properties in bulk and in air. The procedure described
flows through a specified orifice is then determined.
in this method is considered to be more meaningful than
the “flow angle” approach sometimer used to evaluate
The measurements are used to calculate the
bulk flow properties. In the latter, the angle of the cone
fluidization factor 4 and the powder flow rate (flow
formed when a powder is allowed to flow through a verti-
factor) R which together define the transport and
cal funnel on to a horizontal surface is measured. A given
spraying characteristics of the powder.
mass of powder with good flow properties forms a
shallower cone than an equal mass of a powder with
poorer flow. The objections to the flow angle method are
that it is difficult to obtain a precise measurement and that
4 Apparatus
the powder is used alone, whereas during application it is
mixed with air.
4.1 Apparatus for the determination of flow proper-
ties, consisting of a fluidization vessel with a circular
opening in the wall and a device for measuring the
height of powder in the vessel. A means for weigh-
2 Normative reference
ing the amount of powder that flows through the
opening is also included.
The following standard contains provisions which,
through reference in this text, constitute provisions NOTE 2 A suitable apparatus is shown in figure 1 and
described below. Other apparatus may be used if it gives
of this part of IS0 8130. At the time of publication,
comparable results.
the edition indicated was valid. All standards are
subject to revision, and parties to agreements based
A typical apparatus consists of the elements de-
on this part of IS0 8130 are encouraged to investi-
scribed in 4.1.1 to 4.1.3.
gate the possibility of applying the most recent edi-
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IS0 8130-5:1992(E)
4.1.1 Vessel for fluidizing the powder (vessel A),
A 4-mm-diameter circular opening D that can be
outer diameter approximately 110 mm, inner diam- closed with stopper E shall be situated in the wall
eter approximately 100 mm, height not less than
of the vessel, 10 mm above the top of the porous
approximately 200 mm, of transparent
made disc.
poly(methyl methacrylate) and having a bottom
made of a sintered-bronze disc of uniform porosity
4.1.2 Air regulation unit B, with flowmeter F for ad-
and a maximum pore size of approximately 40 pm
justing the air flow.
diameter.
4.1.3 Container C, sufficiently large to collect the
NOTE 3 A disc of 5 mm thickness capable of passing air
powder discharged during measurement of the
at a rate of approximately (ZOO + 10) l/h under
...