JOURNAL PAPER

Bias testing of cross-belt samplers

G. Lyman^I; M. Nel^II; F. Lombard^III; R. Steinhaus^IV; H. Bartlett^V

^IMaterials Sampling and Consulting Pty Ltd, Australia
^IIKumba Iron Ore, South Africa
^IIIUniversity of Johannesburg, South Africa
^IVMultotec Process Equipment, Johannesburg, South Africa
^VConsultant, South Africa

SYNOPSIS

The cross-belt sampler is a device that is very widely used even though it has not been ratified by the Standards associations. This paper is concerned with the bias testing of two cross-belt sampler designs against stopped belt samples and a cross-stream cutter at the belt end. The bias analysis is carried out using size distribution as the analyte and conventional t-testing and the Hotelling T squared test, which are compared for their effectiveness. The paper considers the issue of detectable bias and the statistical planning of bias tests.

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References

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3. LYMAN, G.J. Determination of Bias in Sampling Systems, Minerals Engineering, vol. 6. pp. 99-105.         [ Links ]