ISO 17544:2024

International
Standard
ISO 17544
Second edition
Carbonaceous materials used in
2024-08
the production of aluminium —
Cold and tepid ramming pastes —
Determination of rammability of
unbaked pastes
Produits carbonés utilisés pour la production de l'aluminium —
Pâtes de brasquage froides et tièdes — Détermination de
l'aptitude au brasquage des pâtes non cuites
Reference number
© ISO 2024
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ii
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Symbols . 1
5 Principle . 2
6 Apparatus . 2
7 Sampling . 2
8 Procedure . 3
9 Expression of results . 3
9.1 Calculation of the density .3
9.2 Interpretation of the curve .3
9.3 Determination of N .3
9.3.1 Fitting the data to a Weibull function .3
9.3.2 Calculation of N .4
9.4 Determination of ρ(50)/ρ(100) .4
10 Precision . 4
11 Test report . 5

iii
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
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This document was prepared by Technical Committee ISO/TC 226, Materials for the production of primary
aluminium.
This second edition cancels and replaces the first edition (ISO 17544:2004), which has been technically
revised.
The main changes are as follows:
— the mass of the falling weight and the ramming rate have been corrected.
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
Introduction
The bottom of aluminium electrolysis cells is lined with cathode blocks that are sealed with a ramming
paste to avoid any leakage. When lining a cell, the green paste is directly rammed between the cathode
blocks and baked in situ during the start-up of the pot by the process heat. The quality of the paste is of
primary importance as to ensure long operation without disturbance.

v
International Standard ISO 17544:2024(en)
Carbonaceous materials used in the production of
aluminium — Cold and tepid ramming pastes —
Determination of rammability of unbaked pastes
1 Scope
This document describes a method of producing a compaction curve indicating the rammability of
carbonaceous ramming pastes used to line cathodes utilized in the production of aluminium.
Determination of the rammability enables a ramming paste with the optimum density to be selected.
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 5725-2, Accuracy (trueness and precision) of measurement methods and results — Part 2: Basic method for
the determination of repeatability and reproducibility of a standard measurement method
ISO 14422, Carbonaceous materials used in
...