ISO 12743:2018

INTERNATIONAL ISO
STANDARD 12743
Third edition
2018-06
Copper, lead, zinc and nickel
concentrates — Sampling procedures
for determination of metal and
moisture content
Concentrés de cuivre, de plomb, de zinc et de nickel — Procédures
d'échantillonnage pour la détermination de la teneur en métal et de
l'humidité
Reference number
©
ISO 2018
© ISO 2018
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Contents Page
Foreword .vi
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Sampling theory . 4
4.1 General . 4
4.2 Total variance . 4
4.3 Sampling-stage method of estimating sampling and total variance . 6
4.4 Simplified method of estimating sampling and total variance . 9
4.5 Interleaved sample method of measuring total variance .10
5 Establishing a sampling scheme .12
6 Mass of increment .17
6.1 General .17
6.2 Mass of increment for falling-stream samplers .17
6.3 Mass of increment for cross-belt samplers .17
6.4 Mass of increment for manual sampling from stationary lots .17
6.4.1 Primary increments .17
6.4.2 Mass of secondary and subsequent increments .18
6.5 Mass of increment for stopped-belt reference sampling .18
7 Methods of sampling from concentrate streams .18
7.1 General .18
7.2 Mass-basis systematic sampling .18
7.2.1 General.18
7.2.2 Sampling interval .19
7.2.3 Sample cutter .19
7.2.4 Taking of primary increments .19
7.2.5 Constitution of subsamples and lot samples .19
7.2.6 Types of division .20
7.2.7 Division of increments .20
7.2.8 Division of subsamples .20
7.2.9 Division of lot samples .20
7.3 Time-basis systematic sampling .21
7.3.1 General.21
7.3.2 Sampling interval .21
7.3.3 Sample cutter .21
7.3.4 Taking of primary increments .22
7.3.5 Constitution of subsamples and lot samples .22
7.3.6 Types of division .22
7.3.7 Division of increments and subsamples .22
7.3.8 Division of lot samples .22
7.4 Stratified random sampling .22
7.4.1 Fixed mass intervals .22
7.4.2 Fixed time intervals .23
8 Mechanical sampling of concentrate streams .23
8.1 General .23
8.2 Design of the sampling system .23
8.2.1 Safety of operators .23
8.2.2 Location of sample cutters .23
8.2.3 Provision for interleaved sampling .23
8.2.4 Provision for stratified random sampling .24
8.2.5 Checking precision and bias.24
8.2.6 Avoiding bias .24
8.2.7 Minimizing bias .24
8.2.8 Configuration of the sampling system .24
8.3 Sample cutters .24
8.3.1 General.24
8.3.2 Design criteria .25
8.3.3 Cutter speed .26
8.4 Mass of increments.26
8.5 Number of increments .27
8.6 Sampling interval .27
8.7 Routine checking .27
9 Manual sampling of concentrate streams .28
9.1 General .28
9.2 Choosing the sampling location .28
9.3 Sampling implements .28
9.4 Mass of increments.28
9.5 Number of increments .28
9.6 Sampling interval .28
9.7 Sampling procedures .29
9.7.1 General.29
9.7.2 Full stream cut from a falling stream .29
9.7.3 Partial stream cuts from a falling stream .29
9.7.4 Sampling from moving conveyor belts .30
10 Stopped-belt reference sampling .30
11 Sampling from grabs .
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