3.1 This classification defines a group of classes for use by those producing or purchasing fireclay and high-alumina plastic refractories and ramming mixes. Each class is limited by PCE or alumina content, or both. This classification is frequently used as a specification when the properties shown in Table 1 are the only items specified.

1.1 This classification covers fireclay and high-alumina plastic refractories and ramming mixes that can be pounded or rammed into place to form a monolithic structure. The terms “plastic” and “ramming mix” are generally intended to describe the workability of the material. In this regard, plastics are considered to be materials having a workability index of more than 15 % in accordance with Test Method C181, while ramming mixes generally have less than 15 % workability by the same procedure.

1.2 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.