1.1 本规范涵盖了用于低温液化天然气（LNG）C型储罐的隔热系统的选择和应用要求，该储罐可在比a型或B型储罐更高的压力下储存LNG。 1.2 还详细介绍了安装方法和材料，包括夹套和蒸汽缓凝剂。 1.3 本规范应适用于《国际气体或其他低闪点燃料船舶安全规范》（IGF规范）或《国际散装运输液化气体船舶结构和设备规范》（IGC规范）规定的液化天然气燃料和货船应用。 1.4 本规范对IGC规范第4章所述的C型液化天然气储罐中使用的隔热材料和其他材料的性能提出了要求。 19.3和IGF规范第6.4.13.3节。 1.5 《IGC规范》和《IGF规范》对液化天然气C型储罐进行了说明。 1.6 本规范规定了C型液化天然气储罐或位于暴露甲板上或上方的储罐部分以及未永久保持惰性的货舱（即氧气含量低于5%的大气）的耐火性和火焰蔓延性。 1.7 本规范规定的液化天然气储罐工作温度范围为-259°F（-162°C）+0/-9°F）+0/-5°C至不超过113°F（45°C）的环境温度。 1.8 本规范不涉及真空夹套（即在低于环境压力下运行的隔热系统）隔热液化天然气C型储罐的隔热。 1.9 本规范未涉及可拆卸/可重复使用的隔热系统的设计。 1.10 本规范未涉及绝缘系统的结构设计和物理强度。然而，护套系统的固定问题已得到解决。 1.11 绝缘系统密度不是本规范中考虑的设计标准。 1.12 罐装绝缘管不在本规范的范围内。 1.13 单位-- 以英寸磅为单位的数值应视为标准。括号中给出的值是国际单位制的数学转换，仅供参考，不被视为标准。 1.14 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。 1.15 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。

1.1 This specification covers selection and application requirements for the design of a thermal insulation system used on cryogenic liquefied natural gas (LNG) Type C tanks that can store LNG at a higher pressure than Type A or Type B tanks. 1.2 Methods and materials for installation, including jacketing and vapor retarders, are also detailed. 1.3 This specification shall be applied to LNG fueled and cargo vessel applications as regulated by either the International Code of Safety for Ships Using Gases or Other Low Flashpoint Fuels (IGF Code) or International Code for the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk (IGC Code). 1.4 This specification provides requirements for the properties of thermal insulation and other materials used in LNG Type C tanks as described in IGC Code Chapter 4.19.3 and IGF Code Section 6.4.13.3. 1.5 LNG Type C tanks are described in IGC Code and IGF Code. 1.6 This specification addresses suitable properties of resistance to fire and flame spread for LNG Type C tanks or portions of the tank are located on or above the exposed deck as well in hold spaces that are not maintained permanently inerted (that is, an atmosphere with less than 5 % oxygen). 1.7 The LNG tank operating temperature range addressed by this specification is from a temperature of –259 °F (–162 °C) +0/–9 °F (+0/–5 °C) to ambient temperatures no greater than 113 °F (45 °C). 1.8 This specification does not address the thermal insulation on vacuum jacketed (that is, insulation systems that operate at below ambient pressure) insulated LNG Type C tanks. 1.9 The design of removable/reusable insulation systems is not addressed in this specification. 1.10 Structural design and physical strength of insulation systems are not addressed in this specification. However, the securement of jacketing systems is addressed. 1.11 Insulation system density is not a design criterion considered in this specification. 1.12 Tank-mounted insulated pipe is outside the scope of this specification. 1.13 Units— The values stated in inch-pound units are to be regarded as the standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered standard. 1.14 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. 1.15 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.