1.1 本试验方法涵盖预成型管道保温层在调节后尺寸和密度的测定。 1.1.1 程序A适用于整体式管道覆盖层的截面或可同心连接在一起并作为整体测量的分段式管道覆盖层的截面。 1.1.2 程序B适用于测量每段材料的分段管道覆盖。 1.1.3 程序C适用于一体式管道覆盖物的部分，如软泡沫或矿棉材料，其中可能穿透材料。 1.2 以英寸-磅为单位的数值应视为标准值。括号中给出的值仅供参考。 1.3 本标准并非旨在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、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（TBT）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》中确立的国际公认标准化原则制定的。 ====意义和用途====== 5.1 预制管道保温层的密度测量有助于确定产品是否符合规格限制，并提供产品重量的相对量规。对于任何一种绝缘材料，一些重要的物理和机械性能，如导热系数、热容、强度等，与其密度有特定关系；然而，在密度的基础上，这些特性不能直接与其他类型材料的特性进行比较。 5.2 预制管道保温层的物理尺寸不仅对于确定管道保温层的密度，而且对于确定是否符合规范来说都是重要的参数。 使用多层绝缘是常见的，尺寸是确保层正确嵌套所必需的。

1.1 This test method covers the determination of the dimensions and density, after conditioning, of preformed pipe insulation. 1.1.1 Procedure A is applicable to sections of one-piece pipe covering or to sections of segmental pipe covering that can be joined together concentrically and measured as one-piece. 1.1.2 Procedure B is applicable to segmental pipe covering where each section of material is measured. 1.1.3 Procedure C is applicable to sections of one-piece pipe covering, such as soft foam or mineral wool materials, where it is possible to penetrate the material. 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 ====== 5.1 Density measurements of preformed pipe insulation are useful in determining compliance of a product with specification limits and in providing a relative gage of product weights. For any one kind of insulation some important physical and mechanical properties, such as thermal conductivity, heat capacity, strength, etc., bear a specific relationship with its density; however, on a density basis, these properties are not directly comparable with those for other kinds of material. 5.2 The physical dimensions of preformed pipe insulation are important quantities not only for determining the density of the pipe insulation but also for determining the conformance to specifications. The use of multilayer insulations is common, and the dimensions are necessary to ensure proper nesting of the layers.