1.1本规程分为4部分。这4部分代表先前的标准D 7256/D 7256M ，D 4916 ，D 4702 ，和D 6518 . 这4个标准是管理煤炭机械采样的4个标准，并已合并为一个文件，以便于这些标准的用户参考。 1.2 A部分 — 机械收集和系统内制备移动气流中的总煤样 — 涵盖I-B-1和I-B-2类样品的机械收集程序（实施规程D 2234/D 2234M )以及利用机械采样系统的各种组件在系统内制备（减少和分割）总样本。 1.2.1 A部分描述了煤的机械取样程序 (1) 根据制备的大小和条件（例如，机械净化煤或原煤），以及 (2) 通过采样特征。 1.3 B部分 — 机械螺旋取样 — — 描述了使用机械螺旋钻收集材料增量、部分样品或总样品的程序。还涵盖了螺旋钻处机械设备对材料的减少和分割。其他地方的材料应按照规程D 2013进行进一步的手动或机械还原或分割 . 1.4 C部分 — 机械煤取样系统的质量管理 — 适用于交叉皮带、下降流和螺旋取样系统的质量管理。 1.4.1增量间距与增量之间的间隔类型有关。间隔可以用定量术语定义，例如时间或质量单位，或者根据地块上的位置来定义。 1.4.2 交叉带和落流取样器的增量间距 — 交叉带和下降流式机械采样系统根据时间以固定时间间隔或固定时间段内的随机时间递增。一些落水采样器可以根据比例确定的采样煤的等质量进行增量。本规程中与交叉带和落流采样器相关的章节仅描述了基于时间的采样系统的程序。该基于时间的检验指南将满足基于质量或基于质量和基于时间的组合取样系统的大多数标准。如果有未涵盖的项目，检查员应参考制造商的文献。 1.4.3 螺旋钻取样增量间距 — 螺旋钻取样系统收集的增量间距根据批次上的位置定义。 1.4.4检查员在进行检查时，必须具备本规程第2节中列出的文件。 1.5 D部分 — 机械煤取样系统的偏差测试 — 介绍了用于测试机械采样系统、子系统和单个系统组件的偏差的样本收集和统计评估程序。本规程的用户有责任为特定采样情况选择适当的程序。 1.5.1 D部分无意定义绝对偏差。本规程定义的偏差是机械取样器测试结果的总体平均值与可接受参考值之间的差值。 1.6以国际单位制或英寸-磅单位表示的数值应单独视为标准值。在文本中，英寸-磅单位显示在括号中。每个系统中规定的值可能不是精确的等效值；因此，独立使用每个系统。将两个系统的值合并可能会导致不符合标准。 1.7 本标准并非旨在解决与其使用相关的所有安全问题（如有）。本标准的用户有责任在使用前制定适当的安全和健康实践，并确定监管限制的适用性。 有关具体的危险说明，请参阅第16.1节。 ====意义和用途====== 本规程旨在提供代表所采集煤炭的样本。 由于煤炭的可变性和可用的机械采样设备种类繁多，在样品采集过程、采样系统规范设计、设备采购和已安装设备的验收测试的所有阶段都应谨慎。 从取样系统中移除并进一步准备后（实施规程D 2013 )，可以分析样本的许多不同参数。这些参数可以定义地块的价值、其满足规范的能力、其环境影响以及其他属性。

1.1 This practice is divided into 4 parts. These 4 parts represent the previous standards D 7256/D 7256M , D 4916 , D 4702 , and D 6518 . These 4 standards are the 4 that govern the mechanical sampling of coal and have been combined into one document for the ease of reference of the users of these standards. 1.2 Part A — Mechanical Collection and Within-System Preparation of a Gross Sample of Coal from Moving Streams — 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. 1.2.1 Part A 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 Part B — Mechanical Auger Sampling — — Describes procedures for the collection of an increment, partial sample, or gross sample of material using mechanical augers. Reduction and division of the material by mechanical equipment at the auger is also covered. Further manual or mechanical reduction or division of the material elsewhere shall be performed in accordance with Practice D 2013 . 1.4 Part C — Quality Management of Mechanical Coal Sampling Systems — Is applicable to the quality management of cross-belt, falling stream, and auger sampling systems. 1.4.1 Spacing of increments pertains to the kind of interval between increments. Intervals can be defined in quantitative terms, such as units of time or mass, or in terms of position over the lot. 1.4.2 Spacing of Increments for Cross-Belt and Falling Stream Samplers — Cross-belt and falling stream type mechanical sampling systems take increments based on time, either at fixed time intervals or at random times during a fixed time strata. Some falling stream samplers can take increments based on equal mass of coal sampled as determined by scales. The sections of this practice that pertain to cross-belt and falling stream samplers describe procedures for only time-based sampling systems. This time-based inspection guideline will satisfy most criteria for mass-based or combination mass-based and time-based sampling systems. If there are items that are not covered, the inspector should refer to the manufacturer's literature. 1.4.3 Spacing of Increments for Auger Sampling — The spacing of increments collected by auger sampling systems is defined in terms of position over the lot. 1.4.4 It is essential that the inspector have the documentation listed in Section 2 of this practice when conducting an inspection. 1.5 Part D — Bias Testing of a Mechanical Coal Sampling System — Presents sample collection and statistical evaluation procedures for testing mechanical sampling systems, subsystems, and individual system components for bias. It is the responsibility of the user of this practice to select the appropriate procedure for a specific sampling situation. 1.5.1 Part D does not purport to define an absolute bias. Bias defined by this practice is the difference between the population mean of the mechanical sampler test results and the accepted reference value. 1.6 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. 1.7 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. For a specific hazard statement, see section 16.1. ====== Significance And Use ====== 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.