ISO 18283:2022

INTERNATIONAL ISO
STANDARD 18283
Second edition
2022-03
Coal and coke — Manual sampling
Houille et coke — Échantillonnage manuel
Reference number
© ISO 2022
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Published in Switzerland
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Contents Page
Foreword .v
Introduction .vii
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 Establishing a sampling scheme.4
4.1 General . 4
4.1.1 Sampling . 4
4.1.2 Sampling scheme . 5
4.1.3 Parameters . 5
4.1.4 Sampling methods. 5
4.2 Design of the sampling scheme . 6
4.2.1 General . 6
4.2.2 Coal or coke to be sampled and considerations for sampling . 6
4.2.3 Division of lots . 6
4.2.4 Precision of results . 7
4.2.5 Bias of results . 7
4.2.6 Requirements for test samples . 7
4.3 Precision of sampling . 8
4.3.1 General . 8
4.3.2 Precision and total variance . 8
4.3.3 Primary increment variance . 9
4.3.4 Sub-lot variance . 10
4.3.5 Preparation and testing variance . 10
4.3.6 Number of sub-lots and number of increments per sub-lot . 11
4.3.7 Minimum mass of samples for general analysis and determination of total
moisture content .12
4.4 Checking the overall precision for the lot by calculation and selection of sampling
scheme. 15
4.5 Determination of acquired precision by replicate sampling . 15
4.5.1 General .15
4.5.2 Method and calculation .15
4.5.3 Precision obtained using normal sampling scheme . 16
4.6 Size analysis . 16
5 Methods of sampling .17
5.1 General . 17
5.2 Sampling by time interval (time-basis sampling) . 17
5.3 Sampling by mass interval (mass-basis sampling) . 18
5.4 Stratified random sampling . 18
5.4.1 General . 18
5.4.2 Stratified random sampling by time interval . 18
5.4.3 Stratified random sampling by mass interval . 18
5.5 Extracting the increment . 18
5.6 Coal or coke in motion . 19
5.6.1 General . 19
5.6.2 Stopped belt . 19
5.6.3 Falling stream .20
5.6.4 Moving belt .20
5.6.5 Stockpiles (building/reclaiming) . 21
5.6.6 Grabs/front-end loaders . 21
5.6.7 Barges/trucks/railcars/wagons (loading/unloading) .22
5.7 Moisture/common sample .22
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5.8 Different coals or cokes . 23
5.9 Random selection of increments . 23
6 Sampling equipment .24
6.1 General . 24
6.2 Examples . 25
6.2.1 Ladles. 25
6.2.2 Shovels . 25
6.2.3 Scoops . 25
6.2.4 Probes . 25
6.2.5 Manual cutter . 26
6.2.6 Stopped-belt sampling frame . 26
7 Handling and storage of samples .28
7.1 Sample size . 28
7.2 Time.28
7.3 Divided sample .29
7.4 Containers . .29
7.5 Moisture loss/breakage or degradation .30
7.6 Identification/labelling . 31
8 Sample preparation .31
8.1 General . 31
8.2 Constitution of a sample . 31
8.3 Division . 32
8.3.1 General .
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