StandardDetails

This test method covers the determination of the softening point of a glass by determining the temperature at which a round ?ber of the glass, nominally 0.65 mm in diameter and 235 mm long with speci?ed tolerances, elongates under its own weight at a rate of 1 mm/min when the upper 100 mm of its length is heated in a speci?ed furnace at the rate of 5 ± 1°C/min. 1.2 This method is applicable to all glasses of normal bulk-production composition unless devitrification takes place during the preparation of the specimen. 1.3 The values stated in SI units are to be in this 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 and health practices and determine the applicability of regulatory limitations prior to use.