1.1 本试验方法包括在规定条件下重新加热时绝缘耐火砖的永久线性（和体积）变化的测定。 1.2 以英寸磅为单位的数值应视为标准。括号中给出的值仅供参考。 1.3 本标准并不旨在解决与其使用相关的所有安全问题（如有）。本标准的使用者有责任在使用前制定适当的安全、健康和环境实践，并确定监管限制的适用性。 1.4 本国际标准是根据世界贸易组织技术性贸易壁垒委员会发布的《关于制定国际标准、指南和建议的原则的决定》中确立的国际公认的标准化原则制定的。 ====意义和用途====== 3.1 隔热耐火砖（IFB）按其体积密度和再热变化进行分类（见分类 C155 ). 该试验方法通过在试验温度下测量IFB 24小时后的再热变化来定义热稳定性。 3.2 由于该测试将整个样品暴露在等温温度条件下，用户应该意识到IFB的大多数应用都涉及热梯度，这可能会导致IFB的尺寸发生不同的变化。

1.1 This test method covers the determination of the permanent linear (and volume) change of insulating firebrick upon reheating under prescribed conditions. 1.2 The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are for information only. 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. ====== Significance And Use ====== 3.1 Insulating firebrick (IFB) are classified by their bulk density and reheat change (see Classification C155 ). This test method defines thermal stability by measurement of IFB's reheat change following 24 h at a test temperature. 3.2 Since this test exposes the entire sample to an isothermal temperature condition, the user should be aware that most applications for IFB involve a thermal gradient which may cause the IFB's dimensions to change differentially.