1.1 本试验方法涵盖了在松散（方法A）和抽头（方法B）状态下测定自由流动和中等粘性粉末以及尺寸不超过3.5 mm的颗粒材料体积密度的仪器和程序。 1.2 本试验方法应在受控温度和湿度条件下的实验室中进行。 1.3 本试验方法与试验方法相似 B212页 , B329 , B417页 , D29 和 D2854 . 1.4 所有观察值和计算值应符合实践中确定的有效数字和舍入准则 D6026 . 1.4.1 本标准中用于规定如何收集/记录或计算数据的程序被视为行业标准。 此外，它们代表了通常应保留的有效数字。使用的程序不考虑材料变化、获取数据的目的、特殊目的研究或用户目标的任何考虑因素；通常的做法是增加或减少报告数据的有效位数，以与这些考虑因素相称。考虑工程设计分析方法中使用的有效数字超出了本标准的范围。 1.5 以国际单位制表示的数值应视为标准值。本标准不包括其他计量单位。 1.6 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、健康和环境实践，并确定监管限制的适用性。 1.7 本国际标准是根据世界贸易组织技术性贸易壁垒（TBT）委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 松散堆积密度测试的数据可用于估计在松散状态下储存固定质量粉末的袋子、手提箱、小箱子或料斗的尺寸。它还可用于估计适合小尺寸容器（如桶）的粉末质量。它不能用于估计筒仓等大型容器的粉末量。 5.2 应谨慎使用使用本试验方法获得的松装密度值，因为它们可能会因试样的初始分散状态、量筒中试样的高径比、粉末的干燥度和其他因素而发生很大变化。 5.3 抽头体积密度测试的数据可用于估计装有固定质量粉末的小型容器所需的体积。例如，包装线使用振动将粉末夯实到小容器中，以实现有效包装。 5.4 如果要处理的实际材料的粒径与测试的不同，则体积密度值可能会发生显著变化。由大小颗粒组成的大块固体通常比细颗粒本身具有更高的体积密度。对于粉末而言，如果细颗粒流化或充气，则密度可能较低。 5.5 该试验方法的结果最适用于体积高达约1立方米的容器。另一种方法（例如 D6683 )在考虑较大的筒仓时应使用。 注1: 本标准产生的结果的质量取决于执行该标准的人员的能力，以及所用设备和设施的适用性。符合实践标准的机构 D3740 通常认为能够胜任和客观的测试/采样/检查等。本标准的用户应注意遵守惯例 D3740 本身并不能保证可靠的结果。 可靠的结果取决于许多因素；实践 D3740 提供了一种评估其中一些因素的方法。实践 D3740 是为从事土壤和岩石测试或检查（或两者）的机构开发的。因此，它并不完全适用于执行本标准的机构。然而，本标准的用户应认识到实践框架 D3740 适用于评估执行本标准的机构的质量。目前，没有已知的合格国家机构来检查执行本标准的机构。

1.1 This test method covers the apparatus and procedures for determining the bulk densities of free flowing and moderately cohesive powders and granular materials up to 3.5 mm in size in their loose (Method A) and tapped (Method B) states. 1.2 This test method should be performed in a laboratory under controlled conditions of temperature and humidity. 1.3 This test method is similar to those of Test Methods B212 , B329 , B417 , D29 , and D2854 . 1.4 All observed and calculated values shall conform to the guidelines for significant digits and rounding established in Practice D6026 . 1.4.1 The procedures used to specify how data are collected/recorded or calculated in this standard are regarded as the industry standard. In addition they are representative of the significant digits that generally should be retained. The procedures used do not consider material variations, purpose for obtaining the data, special purpose studies, or any considerations for the user’s objectives; and it is common practice to increase or reduce significant digits of reported data to be commensurate with these considerations. It is beyond the scope of this standard to consider significant digits used in analysis methods for engineering design. 1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard. 1.6 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.7 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee. ====== Significance And Use ====== 5.1 The data from the loose bulk density test can be used to estimate the size of bags, totes, small bins or hoppers for the storage of a fixed mass of powder in its loose condition. It can also be used to estimate the mass of powder that will fit in small size containers such as drums. It cannot be used to estimate powder quantities of large vessels such as silos. 5.2 Values of loose bulk density obtained using this test method should be used with caution, since they can vary considerably depending on the inital state of dispersion of the test specimen, height-to-diameter ratio of specimen in graduated cylinder, dryness of powder, and other factors. 5.3 The data from the tapped bulk density test can be used to estimate the needed volume of small containers holding a fixed mass of powder that has been compacted. An example would be a packing line where vibration is used to tamp powders into a small container for effective packing purposes. 5.4 Bulk density values can vary significantly if the particle size of the actual material to be handled is different than tested. A bulk solid consisting of large and small particles often has higher bulk densities than the fine particles by themselves. For powders, lower densities are possible if the fine particles are fluidized or aerated. 5.5 The results of this test method are most applicable to containers with volumes up to about one cubic meter. Another method (such as D6683 ) should be used when considering larger silos. Note 1: The quality of the results produced by this standard is dependent on the competence of the personnel performing it, and the suitability of the equipment and facilities used. Agencies that meet the criteria of Practice D3740 are generally considered capable of competent and objective testing/sampling/inspection/etc. Users of this standard are cautioned that compliance with Practice D3740 does not in itself assure reliable results. Reliable results depend on many factors; Practice D3740 provides a means of evaluating some of those factors. Practice D3740 was developed for agencies engaged in the testing or inspection (or both) of soil and rock. As such it is not totally applicable to agencies performing this standard. However, users of this standard should recognize that the framework of Practice D3740 is appropriate for evaluating the quality of an agency performing this standard. Currently there is no known qualifying national authority that inspects agencies that perform this standard.