【国外标准】 Standard Practice for Mechanical Collection and Within-System Preparation of a Gross Sample of Coal from Moving Streams (Withdrawn 2008)

It is intended that this practice be used to provide a sample representative of the coal from which it is collected. Because of the variability of coal and the wide variety of mechanical sampling equipment available, caution should be used in all stages of the sample collection process, the design of sampling system specifications, the equipment procurement and the acceptance testing of installed equipment.After removal from the sampling system and further preparation (Practice D 2013), the sample may be analyzed for a number of different parameters. These parameters may define the lot's value, its ability to meet specifications, its environmental impact, as well as other properties.1.1 This practice covers procedures for the mechanical collection of a sample under Classification I-B-1 and I-B-2 (Practice D 2234/D 2234M) and the within-system preparation (reduction and division) of gross samples utilizing various components of the mechanical sampling system.1.2 This practice describes mechanical sampling procedures for coals (1) by size and condition of preparation (for example, mechanically cleaned coal or raw coal) and (2) by sampling characteristics.1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. Within the text the inch-pound units are shown in brackets. The values stated in each system may not be exact equivalents; therefore, use each system independently of the other. Combining values from the two systems may result in nonconformance with the standard.1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory limitations prior to use.