ISO 8840:2021

Refractory materials — Determination of bulk density of granular materials (grain density)

This document specifies three methods for the determination of the bulk density of granular refractory materials (grain density) having a grain size larger than 2 mm: — Method 1: mercury method with vacuum; — Method 2: arrested water absorption method; — Method 3: vacuum method with spin dryer option according to ISO 5017. Method 1 is intended as the reference method. NOTE Depending on the nature of the material tested, the three methods can give different results. Any statement of the value of a bulk density can therefore be accompanied by an indication of the method used or to be used in case of dispute. The same method can be used for the determination of the volume of the sample, for selecting and preparing the sample, for calculating the bulk density and for presenting the test report.

Matériaux réfractaires — Détermination de la masse volumique apparente des matériaux en grains (masse volumique des grains)

General Information

• Status: Published
• Publication Date: 13-Sep-2021
• ICS: 81.080 - Refractories
• Technical Committee: ISO/TC 33 - Refractories
• Drafting Committee: ISO/TC 33/WG 30 - Determination of bulk density of granular materials (grain density)
• Current Stage: 6060 - International Standard published
• Start Date: 14-Sep-2021
• Due Date: 12-Jul-2022
• Completion Date: 14-Sep-2021

Relations

• Revises: ISO 8840:1987 - Refractory materials — Determination of bulk density of granular materials (grain density)
• Effective Date: 23-Apr-2020

Standards Content (Sample)

INTERNATIONAL ISO
STANDARD 8840
Second edition
2021-09
Refractory materials — Determination
of bulk density of granular materials
(grain density)
Matériaux réfractaires — Détermination de la masse volumique
apparente des matériaux en grains (masse volumique des grains)
Reference number
ISO 8840:2021(E)
©
ISO 2021

---------------------- Page: 1 ----------------------
ISO 8840:2021(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2021
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii © ISO 2021 – All rights reserved

---------------------- Page: 2 ----------------------
ISO 8840:2021(E)

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Sampling . 2
6 Preparation, number and test size of samples . 2
6.1 Preparation of samples . 2
6.2 Number of samples . 2
6.3 Mass of test samples . 2
7 Determination of mass of test sample . 2
8 Determination of volume of test sample — Method 1: Mercury method with vacuum .3
8.1 Principle . 3
8.2 Apparatus . 4
8.3 Determination of mass of empty vacuum pycnometer . 5
8.4 Determination of mass of pycnometer filled with mercury . 6
8.5 Determination of mass of pycnometer containing test sample and filled with mercury . 6
8.6 Calculation of volume of test sample . 6
9 Determination of volume of test sample — Method 2: Arrested water absorption method .7
9.1 Apparatus . 7
9.2 Determination of volume of test sample . 7
9.3 Calculation of results . 8
10 Determination of bulk density of test sample — Method 3: Vacuum method with
spin dryer option . 8
10.1 Principle . 8
10.2 Apparatus and materials . 8
10.3 Procedure . 9
10.3.1 Determination of the mass of dry test piece (m ). 9
1
10.3.2 Soaking of the test sample .10
10.3.3 Determination of the apparent mass of the immersed test sample (m )
5
and the mass of the soaked test sample (m ) .10
3
10.4 Calculation of results .12
10.4.1 Calculation of the volume of the test sample (V ) .12
R
10.4.2 Calculation of the bulk density of the test sample (ρ ) .12
R
10.5 Precision and bias .12
10.5.1 Interlaboratory data .12
10.5.2 Precision.12
10.5.3 Bias .13
11 Test report .13
Bibliography .14
© ISO 2021 – All rights reserved iii

---------------------- Page: 3 ----------------------
ISO 8840:2021(E)

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. 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.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee 33, Refractories.
This second edition cancels and replaces the first edition (ISO 8840:1987), which has been technically
revised.
The main changes compared to the previous edition are as follows:
— a new method according to ISO 5017 has been added. It is identical to the method given in EN 993-18
with a suggested improvement to avoid the most influencing factor of the operator.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
iv © ISO 2021 – All rights reserved

---------------------- Page: 4 ----------------------
INTERNATIONAL STANDARD ISO 8840:2021(E)
Refractory materials — Determination of bulk density of
granular materials (grain density)
1 Scope
This document specifies three methods for the determination of the bulk density of granular refractory
materials (grain density) having a grain size larger than 2 mm:
— Method 1: mercury method with vacuum;
— Method 2: arrested water absorption method;
— Method 3: vacuum method with spin dryer option according to ISO 5017.
Method 1 is intended as the reference method.
NOTE Depending on the nature of the material tested, the three methods can give different results. Any
statement of the value of a bulk density can therefore be accompanied by an indication of the method used or to
be used in case of dispute.
The same method can be used for the determination of the volume of the sample, for selecting and
preparing the sample, for calculating the bulk density and for presenting the test report.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 383, Laboratory glassware — Interchangeable conical ground joints
ISO 385-1, Laboratory glassware — Burettes — Part 1: General requirements
ISO 5017, Dense shaped refractory products — Determination of bulk density, apparent porosity and true
porosity
ISO 8656, Refractory products — Raw materials and unshaped products — Sampling
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
grain density
bulk density of granular material
ratio of the mass of a quantity of the material to the total volume of its grains, including the volume of
any closed pores (3.2) within the grains
© ISO 2021 – All rights reserved 1

---------------------- Page: 5 ----------------------
ISO 8840:2021(E)

3.2
closed pore
pore that is not penetrated by a liquid in which the grains are immersed
4 Principle
Measurement of the volume of a given mass of a granular material by displacement of a liquid.
5 Sampling
Sampling shall be carried out in accordance with ISO 8656 or with another standard sampling scheme
agreed between the interested parties.
6 Preparation, number and test size of samples
6.1 Preparation of samples
The material to be tested shall consist of fractions or groups of fractions with grain sizes above 2 mm.
Laboratory samples shall be produced by sieving, after any preliminary comminution of the material
above 5,6 mm grain size. Test results can be affected by the comminution technique and the equipment
used.
Any dust or loose particles adhering to the grains shall be removed before testing by washing or, with
materials sensitive to moisture or humidity, by air blowing.
To improve reproducibility, it is recommended to reduce the distribution of grains from between 2 mm
and 5,6 mm to between 3 mm and 4 mm.
6.2 Number of samples
Take at least three test samples from the laboratory sample and carry out one determination of bulk
density on each test sample.
6.3 Mass of test samples
The mass of test samples depends on the grain size and the homogeneity of the material. Recommended
sizes are shown in Table 1.
Table 1 — Mass of test samples
Size of test samples
Grain fraction
Method
g
mm
Good homogeneity Poor homogeneity
1 100 200
2,0 to 5,6
2 50 50
3,0 to 4,0 3 200 200
7 Determination of mass of test sample
Dry the test sample to constant mass in the drying oven maintained at 110 ± 5 °C and allow it to cool to
ambient temperature in the desiccator. Weigh the test sample to the nearest 0,1 g and a scale graduation
of 0,01 g.
2 © ISO 2021 – All rights reserved

---------------------- Page: 6 ----------------------
ISO 8840:2021(E)

8 Determination of volume of test sample — Method 1: Mercury method with
vacuum
8.1 Principle
Determination of the volume of the test sample by the mercury displacement method with a vacuum
below 3 000 Pa residual pressure, preferably with a residual pressure of 133 Pa.
Method 1 is preferred as a reference method because of its reproducibility and simplicity in use.
However, mercury is known to be a hazardous substance, and therefore method 2 (see Clause 9) is
recommended for all routine purposes.
© ISO 2021 – All rights reserved 3

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ISO 8840:2021(E)

8.2 Apparatus
8.2.1 Vacuum pycnometer, a vessel as shown in Figure 1 (incorporating conical ground glass joints in
accordance with ISO 383).
Key
X view of X (enlarged)
1 holes, Ø ≤ 1 mm
Figure 1 — Vacuum pycnometer
4 © ISO 2021 – All rights reserved

---------------------- Page: 8 ----------------------
ISO 8840:2021(E)

8.2.2 Test arrangement, as shown in Figure 2.
Key
1 dish for mercury
2 stopcock 2
3 pycnomet
...

INTERNATIONAL ISO
STANDARD 8840
Second edition
Refractory materials — Determination
of bulk density of granular materials
(grain density)
Matériaux réfractaires — Détermination de la masse volumique
apparente des matériaux en grains (masse volumique des grains)
PROOF/ÉPREUVE
Reference number
ISO 8840:2021(E)
©
ISO 2021

---------------------- Page: 1 ----------------------
ISO 8840:2021(E)

COPYRIGHT PROTECTED DOCUMENT
© ISO 2021
All rights reserved. Unless otherwise specified, or required in the context of its implementation, no part of this publication may
be reproduced or utilized otherwise in any form or by any means, electronic or mechanical, including photocopying, or posting
on the internet or an intranet, without prior written permission. Permission can be requested from either ISO at the address
below or ISO’s member body in the country of the requester.
ISO copyright office
CP 401 • Ch. de Blandonnet 8
CH-1214 Vernier, Geneva
Phone: [phone]
Email: [e-mail]
Website: www.iso.org
Published in Switzerland
ii PROOF/ÉPREUVE © ISO 2021 – All rights reserved

---------------------- Page: 2 ----------------------
ISO 8840:2021(E)

Contents Page
Foreword .iv
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Principle . 2
5 Sampling . 2
6 Preparation, number and test size of samples . 2
6.1 Preparation of samples . 2
6.2 Number of samples . 2
6.3 Mass of test samples . 2
7 Determination of mass of test sample . 2
8 Determination of volume of test sample — Method 1: Mercury method with vacuum .3
8.1 Principle . 3
8.2 Apparatus . 4
8.3 Determination of mass of empty vacuum pycnometer . 5
8.4 Determination of mass of pycnometer filled with mercury . 6
8.5 Determination of mass of pycnometer containing test sample and filled with mercury . 6
8.6 Calculation of volume of test sample . 6
9 Determination of volume of test sample — Method 2: Arrested water absorption method .7
9.1 Apparatus . 7
9.2 Determination of volume of test sample . 7
9.3 Calculation of results . 8
10 Determination of bulk density of test sample — Method 3: Vacuum method with
spin dryer option . 8
10.1 Principle . 8
10.2 Apparatus and materials . 8
10.3 Procedure . 9
10.3.1 Determination of the mass of dry test piece (m ). 9
1
10.3.2 Soaking of the test sample .10
10.3.3 Determination of the apparent mass of the immersed test sample (m )
5
and the mass of the soaked test sample (m ) .10
3
10.4 Calculation of results .12
10.4.1 Calculation of the volume of the test sample (V ) .12
R
10.4.2 Calculation of the bulk density of the test sample (ρ ) .12
R
10.5 Precision and bias .12
10.5.1 Interlaboratory data .12
10.5.2 Precision.12
10.5.3 Bias .13
11 Test report .13
Bibliography .14
© ISO 2021 – All rights reserved PROOF/ÉPREUVE iii

---------------------- Page: 3 ----------------------
ISO 8840:2021(E)

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. 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.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular, the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www .iso .org/ directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www .iso .org/ patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation of the voluntary nature of standards, the meaning of ISO specific terms and
expressions related to conformity assessment, as well as information about ISO's adherence to the
World Trade Organization (WTO) principles in the Technical Barriers to Trade (TBT), see www .iso .org/
iso/ foreword .html.
This document was prepared by Technical Committee 33, Refractories.
This second edition cancels and replaces the first edition (ISO 8840:1987), which has been technically
revised.
The main changes compared to the previous edition are as follows:
— a new method according to ISO 5017 has been added. It is identical to the method given in EN 993-18
with a suggested improvement to avoid the most influencing factor of the operator.
Any feedback or questions on this document should be directed to the user’s national standards body. A
complete listing of these bodies can be found at www .iso .org/ members .html.
iv PROOF/ÉPREUVE © ISO 2021 – All rights reserved

---------------------- Page: 4 ----------------------
INTERNATIONAL STANDARD ISO 8840:2021(E)
Refractory materials — Determination of bulk density of
granular materials (grain density)
1 Scope
This document specifies three methods for the determination of the bulk density of granular refractory
materials (grain density) having a grain size larger than 2 mm:
— Method 1: mercury method with vacuum;
— Method 2: arrested water absorption method;
— Method 3: vacuum method with spin dryer option according to ISO 5017.
Method 1 is intended as the reference method.
NOTE Depending on the nature of the material tested, the three methods can give different results. Any
statement of the value of a bulk density can therefore be accompanied by an indication of the method used or to
be used in case of dispute.
The same method can be used for the determination of the volume of the sample, for selecting and
preparing the sample, for calculating the bulk density and for presenting the test report.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
ISO 383, Laboratory glassware — Interchangeable conical ground joints
ISO 385-1, Laboratory glassware — Burettes — Part 1: General requirements
ISO 5017, Dense shaped refractory products — Determination of bulk density, apparent porosity and true
porosity
ISO 8656, Refractory products — Raw materials and unshaped products — Sampling
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https:// www .iso .org/ obp
— IEC Electropedia: available at https:// www .electropedia .org/
3.1
grain density
bulk density of granular material
ratio of the mass of a quantity of the material to the total volume of its grains, including the volume of
any closed pores (3.2) within the grains
© ISO 2021 – All rights reserved PROOF/ÉPREUVE 1

---------------------- Page: 5 ----------------------
ISO 8840:2021(E)

3.2
closed pore
pore that is not penetrated by a liquid in which the grains are immersed
4 Principle
Measurement of the volume of a given mass of a granular material by displacement of a liquid.
5 Sampling
Sampling shall be carried out in accordance with ISO 8656 or with another standard sampling scheme
agreed between the interested parties.
6 Preparation, number and test size of samples
6.1 Preparation of samples
The material to be tested shall consist of fractions or groups of fractions with grain sizes above 2 mm.
Laboratory samples shall be produced by sieving, after any preliminary comminution of the material
above 5,6 mm grain size. Test results can be affected by the comminution technique and the equipment
used.
Any dust or loose particles adhering to the grains shall be removed before testing by washing or, with
materials sensitive to moisture or humidity, by air blowing.
To improve reproducibility, it is recommended to reduce the distribution of grains from between 2 mm
and 5,6 mm to between 3 mm and 4 mm.
6.2 Number of samples
Take at least three test samples from the laboratory sample and carry out one determination of bulk
density on each test sample.
6.3 Mass of test samples
The mass of test samples depends on the grain size and the homogeneity of the material. Recommended
sizes are shown in Table 1.
Table 1 — Mass of test samples
Size of test samples
Grain fraction
Method
g
mm
Good homogeneity Poor homogeneity
1 100 200
2,0 to 5,6
2 50 50
3,0 to 4,0 3 200 200
7 Determination of mass of test sample
Dry the test sample to constant mass in the drying oven maintained at 110 ± 5 °C and allow it to cool to
ambient temperature in the desiccator. Weigh the test sample to the nearest 0,1 g and a scale graduation
of 0,01 g.
2 PROOF/ÉPREUVE © ISO 2021 – All rights reserved

---------------------- Page: 6 ----------------------
ISO 8840:2021(E)

8 Determination of volume of test sample — Method 1: Mercury method with
vacuum
8.1 Principle
Determination of the volume of the test sample by the mercury displacement method with a vacuum
below 3 000 Pa residual pressure, preferably with a residual pressure of 133 Pa.
Method 1 is preferred as a reference method because of its reproducibility and simplicity in use.
However, mercury is known to be a hazardous substance, and therefore method 2 (see Clause 9) is
recommended for all routine purposes.
© ISO 2021 – All rights reserved PROOF/ÉPREUVE 3

---------------------- Page: 7 ----------------------
ISO 8840:2021(E)

8.2 Apparatus
8.2.1 Vacuum pycnometer, a vessel as shown in Figure 1 (incorporating conical ground glass joints in
accordance with ISO 383).
Key
X view of X (enlarged)
1 holes, Ø ≤ 1 mm
Figure 1 — Vacuum pycnometer
4 PROOF/ÉPREUVE © ISO 2021 – All rights reserved

---------------------- Page: 8 ----------------------
ISO 8840:2021(E)

8.2.2 Test arrangement, as shown in Figure 2.
Key
1 dish for mercury
2 stopcock 2
3 pycnometer lower part
4 glass se
...