1.1本试验方法包括通过测量简单加载玻璃梁的中点粘性弯曲速率来确定玻璃的退火点和应变点。 然而，在对应于退火和应变点的温度下，玻璃的粘度高度依赖于时间。因此，不能假设通过该程序测量得出或推断出的任何粘度代表平衡结构条件。 1.2退火点和应变点应在使用具有已知退火点和应变点的标准玻璃梁（如国家标准与技术研究所提供和认证的标准玻璃梁）直接校准仪器后，按照规定程序获得。 1.3本试验方法，作为试验方法的替代方法 C 336 特别适用于因某种原因不适合火焰加工的眼镜。它还具有消除纤维伸长法常见的热膨胀和有效长度修正的优点。 1.4以公制单位表示的数值应视为标准。括号中给出的值仅供参考。 1.5本标准无意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和健康实践，并确定监管限制的适用性。

1.1 This test method covers the determination of the annealing point and the strain point of a glass by measuring the rate of midpoint viscous bending of a simply loaded glass beam. However, at temperatures corresponding to the annealing and strain points, the viscosity of glass is highly time-dependent. Hence, any viscosities that might be derived or inferred from measurements by this procedure cannot be assumed to represent equilibrium structural conditions. 1.2 The annealing and strain points shall be obtained following a specified procedure after direct calibration of the apparatus using beams of standard glasses having known annealing and strain points such as those supplied and certified by the National Institute of Standards and Technology. 1.3 This test method, as an alternative to Test Method C 336 is particularly well suited for glasses that for one reason or another are not adaptable for flame working. It also has the advantages that thermal expansion and effective length corrections, common to the fiber elongation method, are eliminated. 1.4 The values stated in metric units are to be regarded as the standard. The values given in parentheses are for information only. 1.5 This standard does not purport to address all of the safety problems, 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.