4.1 This test method was developed for use both by manufacturers as a process control tool for the production of AZS fusion-cast refractories, and by glass manufacturers in the selection of refractories and design of glass-melting furnaces.

4.2 The results may be considered as representative of the potential for an AZS refractory (specifically, in the tested region) to contribute to glass defect formation during the furnace production operation.

4.3 The procedures and results may be applied to other refractory types or applications (that is, reheat furnace skid rail brick) in which glass exudation is considered to be important.

1.1 This test method covers a procedure for causing the exudation of a glassy phase to the surface of fusion-cast specimens by subjecting them to temperatures corresponding to glass furnace operating temperatures.

1.2 This test method covers a procedure for measuring the exudate as the percent of volume increase of the specimen after cooling.

1.3 Units—The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.5 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.