1.1 本指南旨在规定核燃料溶解设施的设计、制造和安装标准和程序。本指南适用于并涵盖燃料剪切操作（未涵盖）以外的所有加工步骤或操作，直至并包括溶解责任容器。 1.2 适用性和除外条款: 1.2.1、 操作- 本指南不包括核燃料溶解设施的操作。注意到一些操作注意事项会对设计产生影响。 1.2.1.1 解散程序- 燃料成分、燃料元件几何形状和燃料制造方法会随着新反应堆设计和要求的要求而不断变化。这些变化排除了适用于处理所有可能燃料类型的溶解器的设计考虑因素。本指南仅涉及截至本指南发布（或修订）时在反应堆中使用最广泛的燃料的溶解循环相关设备。（参见 附录X1 .） 1. 2.2 流程- 本指南涵盖了压水反应堆（PWR）目前使用的燃料类型的核燃料溶解设施的设计、制造和安装。沸水反应堆（BWR）、加压重水反应堆（PHWR）和重水反应堆（HWR）以及本文讨论的燃料溶解处理技术。然而，所提供的许多信息和标准可能适用于其他溶解过程的设备，如典型研究反应堆的浓缩铀铝燃料，以及一些钍和钚的溶解过程- 含有燃料和其他物质。本指南未涉及高燃耗或混合氧化物燃料溶解的设备设计。 1.2.2.1 本指南不涉及可能需要与上述燃料类型相关的设备或造成不同危险的特殊溶解过程。排除情况的例子是电解溶解和钠结合燃料加工。该指南未涉及连续溶解器的设计和制造。 1.2.3 附属或辅助设施（例如蒸汽、冷却水、电气服务）不包括在内。 简要介绍了冷化学进料的注意事项。 1.2.4 溶解预处理- 本指南不包括为溶解后处理准备乏燃料组件所附带的燃料预处理步骤。这一排除适用于热处理步骤，如溶解前排出气体的“Voloxidation”，与燃料元件拆卸和端部配件拆卸相关的机械解密操作或工艺步骤，切碎和剪切操作，以及被认为对有效核燃料溶解步骤至关重要的任何其他预处理操作。 1.2.5 基础知识- 本指南不涉及特定的化学、物理或机械技术、流体力学、应力分析或其他工程基础，这些基础也适用于核燃料溶解设施的安全设计。 1.3 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。 1.4 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。 1.5 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====== 4.1 本指南旨在提供有助于确保以经济高效的方式构思、设计、制造、建造和安装核燃料溶解设施的信息。本指南将有助于设施满足预期性能功能，消除或最大限度地减少核临界的可能性，并在正常和异常（紧急）运行条件下以及在可信的故障或事故条件下为操作人员和公众提供保护。

1.1 It is the intent of this guide to set forth criteria and procedures for the design, fabrication and installation of nuclear fuel dissolution facilities. This guide applies to and encompasses all processing steps or operations beyond the fuel shearing operation (not covered), up to and including the dissolving accountability vessel. 1.2 Applicability and Exclusions: 1.2.1 Operations— This guide does not cover the operation of nuclear fuel dissolution facilities. Some operating considerations are noted to the extent that these impact upon or influence design. 1.2.1.1 Dissolution Procedures— Fuel compositions, fuel element geometry, and fuel manufacturing methods are subject to continuous change in response to the demands of new reactor designs and requirements. These changes preclude the inclusion of design considerations for dissolvers suitable for the processing of all possible fuel types. This guide will only address equipment associated with dissolution cycles for those fuels that have been used most extensively in reactors as of the time of issue (or revision) of this guide. (See Appendix X1 .) 1.2.2 Processes— This guide covers the design, fabrication and installation of nuclear fuel dissolution facilities for fuels of the type currently used in Pressurized Water Reactors (PWR). Boiling Water Reactors (BWR), Pressurized Heavy Water Reactors (PHWR) and Heavy Water Reactors (HWR) and the fuel dissolution processing technologies discussed herein. However, much of the information and criteria presented may be applicable to the equipment for other dissolution processes such as for enriched uranium-aluminum fuels from typical research reactors, as well as for dissolution processes for some thorium and plutonium-containing fuels and others. The guide does not address equipment design for the dissolution of high burn-up or mixed oxide fuels. 1.2.2.1 This guide does not address special dissolution processes that may require substantially different equipment or pose different hazards than those associated with the fuel types noted above. Examples of precluded cases are electrolytic dissolution and sodium-bonded fuels processing. The guide does not address the design and fabrication of continuous dissolvers. 1.2.3 Ancillary or auxiliary facilities (for example, steam, cooling water, electrical services) are not covered. Cold chemical feed considerations are addressed briefly. 1.2.4 Dissolution Pretreatment— Fuel pretreatment steps incidental to the preparation of spent fuel assemblies for dissolution reprocessing are not covered by this guide. This exclusion applies to thermal treatment steps such as “Voloxidation” to drive off gases prior to dissolution, to mechanical decladding operations or process steps associated with fuel elements disassembly and removal of end fittings, to chopping and shearing operations, and to any other pretreatment operations judged essential to an efficient nuclear fuels dissolution step. 1.2.5 Fundamentals— This guide does not address specific chemical, physical or mechanical technology, fluid mechanics, stress analysis or other engineering fundamentals that are also applied in the creation of a safe design for nuclear fuel dissolution facilities. 1.3 The values stated in inch-pound units are to be regarded as standard. The values given in parentheses are mathematical conversions to SI units that are provided for information only and are not considered 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use. 1.5 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 ====== 4.1 The purpose of this guide is to provide information that will help to ensure that nuclear fuel dissolution facilities are conceived, designed, fabricated, constructed, and installed in an economic and efficient manner. This guide will help facilities meet the intended performance functions, eliminate or minimize the possibility of nuclear criticality and provide for the protection of both the operator personnel and the public at large under normal and abnormal (emergency) operating conditions as well as under credible failure or accident conditions.