ASTM D8641-25

1.1 This test method covers the determination of the pour density of pelleted or granulated silica.

1.2 Units—The values stated in SI units are to be regarded as the standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered standard.

1.3 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.

1.4 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.

4.1 Pour density is a function of the degree of compaction of pellets or granulates of silica. Pour density of silica is useful for estimating the weight-to-volume relationship for certain applications, such as automatic batch loading systems, and for estimating weights of bulk shipments.

4.2 A similar test method is known for carbon black, see Test Method D1513.