ISO 8264:1989
(Main)Hard coal — Determination of the swelling properties using a dilatometer
Hard coal — Determination of the swelling properties using a dilatometer
A test piece, in the form of a pencil, prepared from powdered coal is heated at a constant rate in a steel retort positioned in a furnace, the temperature monitoring system having been previously calibrated using two reference metals of known melting points. The change in level of a piton resting upon the test piece is observed continuously, and record is produced which is characteristic of the swelling properties of the coal.
Houille — Détermination des propriétés de gonflement à l'aide d'un dilatomètre
Črni premog - Ugotavljanje lastnosti nabrekanja z dilatometrom
General Information
Standards Content (Sample)
SLOVENSKI STANDARD
01-maj-1998
ýUQLSUHPRJ8JRWDYOMDQMHODVWQRVWLQDEUHNDQMD]GLODWRPHWURP
Hard coal -- Determination of the swelling properties using a dilatometer
Houille -- Détermination des propriétés de gonflement à l'aide d'un dilatomètre
Ta slovenski standard je istoveten z: ISO 8264:1989
ICS:
73.040 Premogi Coals
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.
INTERNATIONAL ISO
STANDARD
First edition
1989-11-15
Hard coal - Determination of the swelling
properties using a dilatometer
Hode - Determination des propri&$s de gonflement h l’aide d’un dilatomt$tre
Reference number
ISO 8264 : 1989 (EI
ISO8264:1989 (EI
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of
national Standards bodies (ISO member bodies). The work of preparing International
Standards is normally carried out through ISO technical committees. Esch 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. ISO
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 approval before their acceptance as International Standards by
the ISO Council. They are approved in accordance with ISO procedures requiring at
least 75 % approval by the member bodies voting.
International Standard ISO 8264 was prepared by Technical Committee ISO/TC 27,
Solid mineral fuels.
0 ISO 1989
All rights reserved. No part of this publication may be reproduced or utilized in any form or by any
means, electronie 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
ISO 8264 : 1989 (El
Introdwction
The Audibert-Arnu dilatometer test was adopted as ISO Recommendation
ISO/R 349 : 1963 which was transformed into an International Standard
ISO 349 : 1975. When reviewed in 1980, it was generally acknowledged that similar
tests, using slightly different equipment and techniques, were used in various coun-
tries. One test in widespread use was that which measures the swelling properties of
hard coal using the Ruhr dilatometer.
A thorough Survey of the construction and Operation of this instrument was made
between 1973 and 1978 by a working group in the United Kingdom. Eleven laboratories
participated in the work, including two which operated the Audibert-Arnu dilatometer
as described in ISO 349. In the course of considerable inter-laboratory testing, the
results indicated that values of contraction and dilatation found with the Audibert-
Arnu dilatometer were higher and lower respectively than those found with the
modified Ruhr dilatometer (the version described in this International Standard).
These differentes were attributed to the fact that the excess material from the tapered
test piece is removed from the wider end in the Audibert version of the dilatometer test
and from the narrower end in the Ruhr Version. The latter procedure ensures a test
piece of greater and more uniform volume.
lt is not intended that ISO 349 be withdrawn immediately, however it is suggested that
the test be gradually phased out and replaced by that described in this International
Standard, a test which has been tried and proven, particularly in the United Kingdom
and the Federal Republic of Germany, and shown to be reliable and suitable for
measuring the swelling properties of all types of hard coal.
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INTERNATIONAL STANDARD ISO 8264 : 1989 (E)
- Determination of the swelling properties
Hard coal
using a dilatometer
34 . maximum contraction : The maximum downward
1 Scope
movement of the dilatometer Piston, measured from the zero
This International Standard specifies a method for the Point and expressed as a percentage of the initial test piece
length.
measurement of the swelling of hard coal using a dilatometer.
NOTE - See c in figures 3 and 4.
2 Normative references
35 maximum dilatation: The maximum upward move-
The foilowing Standards contain provisions which, through
ment of the dilatometer Piston after contraction, measured
reference in this text, constitute provisions of this International
from the zero Point and expressed as a percentage of the initial
Standard. At the time of publication, the editions indicated
test piece length.
were valid. All Standards are subject to revision, and Parties to
agreements based on this International Standard are encour-
NOTE - See d in figures 3 and 4. The value tan be either positive or
aged to investigate the possibility of applying the most recent
negative.
editions of the Standards indicated below. Members of IEC and
ISO maintain registers of currently valid International Stan-
3.6 repeatability: The maximum acceptable differente
dards.
between two determinations which are carried out in the same
Iaboratory, by the same Operator with the same apparatus, on
ISO 428 : 1983, Wrought topper-aluminium alloys - Chemical
test pieces prepared from the same test Sample and tested
composition and forms of wrought products.
simultaneously in two different retorts during the same heating
cycle or separately in the same retort during different heating
ISO 683- 1 : 1987, Heat- treatable steels, alo y steels and free-
cycles.
cutting steels - Part 7: Direct-hardening unalloyed and low-
alo yed wrought steel in form of different black products.
3.7 reproducibility: The maximum acceptable differente
ISO 1988 : 1975, Hard coal - Sampling.
between the means of two determinations which are carried
out in each of two laboratories, on representative portions
taken from the sarne gross Sample, after the last Stage of
Sample preparation.
3 Definitions
For the purposes of this International Standard, the following
definitions apply.
4 Principle
A test piece, in the form of a pencil, prepared from powdered
3.1 softening temperature; temperature of initial con-
traction: The temperature at which the downward movement coal is heated at a constant rate in a steel retort positioned in a
furnace, the temperature monitoring System having been
of the dilatometer Piston is 0,5 mm.
previously calibrated using two reference metals of known
NOTE - See 8, in figure 3. melting Points. The Change in level of a Piston restiny upon the
test piece is observed continuously, and a record is produced
which is characteristic of the swelling properties of the coal.
3.2 temperature of maximum contraction: The tem-
perature at which the dilatometer Piston reaches its lowest
Point.
5 Materials
NOTE - See 0, in figure 3.
The following materials are required for temperature calibration
(7.1).
3.3 resolidification temperature; temperature of maxi-
mum dilatation: The temperature at which the dilatometer
Piston reaches its highest Point. 5.1 Graphite pencils, 30 mm long, base diameter 7,4 mm,
top diameter 6,8 mm, with a small cylindrical reservoir drilled in
NOTE - See 0, in figure 3. the narrow end of each pencil.
ISO 8264 : 1989 (El
Heat the furnace at a rate of 3 K/min, and measure the
Metal balls, of the following reference metals:
5.2
temperature at the Standard sensing Point, i.e. at a Position
equivalent to that of the centre of a normally sited test piece
a) lead, analytical reagent grade, assay (Pb) 99,98 %
30 mm above the internal base of a retort. When the tem-
minimum, melting Point 327,0 OC;
perature has reached about 450 OC, measure the temperature
b) zinc, assay (Zn) 99,87 % minimum, melting Point over the lower 250 mm of the retort. The differente between
419,3 OC. the probe temperature and the mean temperature shown at the
Standard temperature sensing Position shall be not more than:
5.3 Water-based blacking.
2 K in the lower 120 mm;
5 K from 120 mm to 180 mm;
6 Apparatus
IO K from 180 mm to 250 mm.
6.1 Mould and accessories
NOTE - The instrument used to measure the temperature may either
be the recorder described in 6.5 or another of at least equal precision.
6.1.1 Mould (see figure 11, made from steel, case-hardened
after machining. The bore shall be polished after hardening and
A suitable furnace (for heating three retorts) is illustrated in
the bore and uniformity of taper (i.e. 1 in 50) shall conform to
figure 2 and consists of a casting fitted with a base and a top
the dimensions given in table 1.
cover. The cover supports in a centre hole a cylindrical block of
topper-aluminium alloy (CuAIlONi5Fe4), complying with
Table 1 - Dimensions of mould for dilatometer test ISO 428, as manufactured (i.e. not annealed), of 65 mm
diameter and 460 mm long. The block has three holes of
Dimensions in millimetres
380 mm minimum depth and 15,0 mm I!I 0,l mm diameter,
Distance
drilled as shown in figure 2. The top surface may be insulated
Bore
from
by an appropriately shaped piece of board. The block is heated
(tolerante : - o,oo, + 0,051
wide end
electrically by an insulated resistance winding, capable of rais-
7,4
ing the temperature of the block to 550 OC at a rate of 3 K/min.
10 7,2
The space between the block and the casing is filled with a
20 7,O thermal insulating material. A suitable temperature Sensor is
positioned in the third retort in such a way that the Sensor tip
lies centrally 30 mm above the internal base of the retort. The
distance of 30 mm is established by using a graphite pencil
6,4
(5.1) as a means of measurement.
6.4 Temperature controller
NOTE - Information on suitable gauges for this purpose may be
obtained from the British Coal Corporation, Coal Research
Establishment, Stoke Orchard, Cheltenham, United Kingdom. The temperature controller shall be a separate instrument from
that used to record the rise of temperature during the test.
lt shall be of the automatic, programmed type capable
6.1.2 Mallet, plastics head, mass about 200 g.
of maintaining a mean rate of temperature rise of
3 K/min + 0,05 K/min between 250 OC and 550 OC with a
Variation of not more than * 1 K per 30 K rise in any 10 min
Ram (d) (see figure 1).
6.1.3
period, with a precision of + 1 K.
6.1.4 Press (sec figure 1).
6.5 Temperature recorder
6.1.5 Load cell (h) (see figure l), capable of registering a load
A suitable means of producing a complete record of the
of 0 to 15 kN.
temperature Variation during the test.
6.1.6 Test piece gauge (i) (see figure 1).
6.6 Retort and Piston
6.2 Dilatometer
A cylindrical retort of cold-drawn seamless tube of steel, type
28 Mn6 complying with ISO 683-1, fitted with a gas-tight
A general arrangement of suitable dila tometer apparatus giving
threaded plug at its base and a collar at its top. When inserted
critical dimensions is shown in figure 2.
in a hole in the furnace, the retort shall be supported only by
the collar with the threaded plug clear of the bottom of the
6.3 Dilatometer furnace hole.
A furnace capable of heating two or more retorts (6.6) to a When new, the internal diameter of the retort shall be
8,00 mm + 0,05 mm and the external diameter shall be
temperature of 550 OC at a rate of 3 K/min. The furnace shall
comply with the following operating conditions. 14,5 mm + 0,l mm. Check the internal diameter with a suitable
ISO 8264 : 1989 (E)
ball gauge when new, and again after 100, 150,200, etc., tests. piece (see 7.2.2) by a prepared graphite pencil. Repeat this
If the internal diameter of the lower third of the retort has procedure using a zinc ball 15.2 b)l.
increased at any Point to more than 8,075 mm, discard the
Before re-using graphite pencils heat the narrow end of each
retort.
pencil in a bunsen flame for a few seconds and Shake the
The Piston is machined from rod made of steel, type C 55 com- molten metal from the cylindrical reservoir.
plying with ISO 683-1. Adjust the combined mass of the Piston
Repeat the calibration after 200 tests or after 3 months’ use,
and pen assembly to 150 g + 5 g by machining Cut-out
whichever occurs first, or if any component is replaced.
portions from the Piston. The differente between the diameter
of the Piston and the internal diameter of the retort shall be
If the differente between the Standard and indicated tem-
0,2 mm k 0,05 mm on manufacture. If this differente exceeds
peratures is less than 7 K, establish a factor to correct the
0,275 mm in use the Piston shall be replaced. The Piston shall
indicated temperatures. If the differente is greater than 7 K,
slide freely in the retort.
check the sensor/indicator System by, for example, direct
potentiometric calibration against a Standard e. m.f.
provided Ilow the retorts and pistons to
A stand shall be to a
cool in a vertical Position a fter removal from the fu rnace.
7.2 Preparation of test Sample and test pieces
6.7 Means of recording Piston movement
7.2.1 Test Sample
A suitable means of recording Piston movement versus time on
a Chart shall be used. The horizontal scale (time) shall be such
7.2.1.1 General
that, when converted to temperature (see 7.3.31, a range of
180 OC will occupy a length of at least 150 mm. On the vertical
Two alternative methods of preparing the test Sample are
scale, 5 % expansion or contraction shall occupy at least
described. If the determination is to be carried out immediately
3 mm. This may be achieved either by a mechanical pen/chart
after preparation of the test Sample, direct size reduction
System or a transducer/electricaI Signal recorder.
(7.2.1.2) ma y b e used. If there is likely to be a delay between
size reduction and testing, or if a laboratory Sample with an
A simple mechanical System is illustrated in figure 2. In this
upper particle size of 600 Fm is required for other tests, the
example two tests are recorded simultaneously on opposite
method described in 7.2.1.3 shall be used. In all cases the pro-
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