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INTERNATIONAL
8875
STANDARD
Second edition
1992-12-15
All grades of fluorspar - Determination of
moisture content of a lot
Dktermina bon de /‘humidit d ‘un lot
Tous /es spaths fluor -
Reference number
IS0 8875:1992(E)
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IS0 8875:1992(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, governmental
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 International
Standard requires approval by at least 75 % of the member bodies casting
a vote.
International Standard IS0 8875 was prepared by Technical Committee
ISOPC 175, Fluorspar.
This second edition cancels and replaces the first edition
(IS0 8875:1988), which has been updated.
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 per-
mission in writing from the publisher.
International Organization for Standardization
Case Postale 56 l CH-1211 Geneve 20 l Switzerland
Printed in Switzerland
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IS0 8875: 1992(E)
INTERNATIONAL STANDARD
- Determination of moisture
All grades of fluorspar
content of a lot
5.2 Drying oven, equipped with a temperature indi-
1 Scope
cator and a control apparatus capable of regulating the
temperature at any point in the oven to
This International Standard specifies a method of de-
105 “C + 5 “C, and designed to maintain this tem-
termining the mean value of the moisture content of
perature. In addition, to ensure efficient drying, the
a lot of fluorspar.
oven is fitted with a fan which circulates air through
This method is applicable to all grades of fluorspar, i.e. the oven at such a rate that the total volume of air in
the oven is changed at least three times per hour,
acid-grade, ceramic-grade and the three metallurgical-
without causing any loss of the sample.
grades (concentrate, briquettes and gravel).
5.3 Weighing device, having a sensitivity of 1 g or
2 Normative reference
better, and an accuracy which will ensure repeatability
at the precision required.
The following standard contains provisions which,
through reference in this text, constitute provisions The weighing device shall be protected from the ef-
of this International Standard. At the time of publi-
fects of the hot drying pan by using a suitable insu-
cation, the edition indicated was valid. All standards lating material.
are subject to revision, and parties to agreements
based on this International Standard are encouraged
6 Test samples
to investigate the possibility of applying the most re-
cent edition of the standard indicated below. Mem-
Test samples shall be taken and prepared in accord-
bers of IEC and IS0 maintain registers of currently
ance with IS0 8868:1989, clause 6 and sub-clause
valid International Standards.
9.2. Two or more test samples shall be prepared per
lot. The entire quantity of each test sample shall be
IS0 8868: 1989, Fluorspar - Sampling and sample
used as the test portion for each moisture determi-
preparation.
nation. The mass of the test portion shall be 1 kg or
larger, and the nominal top size shall be - 10 mm.
3 Definitions
7 Procedure
For the purposes of this International Standard, the
definitions given in IS0 8868 apply.
7.1 Number of determinations
4 Principle
One moisture determination shall be carried out on
each test portion.
Drying of a test portion in air at 105 “C + 5 “C to
-
constant mass.
7.2 Determination
Weigh the drying pan (5.1) to the nearest 1 g.
5 Apparatus
Spread the test portion in the drying pan, in a layer
5.1 Drying pan, having a smooth surface, free from not thicker than 10 mm, and weigh immediately to
impurities and capable of accommodating 1 kg or the nearest 1 g. Record the mass of the drying pan
more of sample in a layer not thicker than 10 mm. and the total mass of the drying pan plus test portion.
1
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