1.1 本规范 2 涵盖压力系统中使用的锻造低合金和不锈钢管道部件。包括法兰、配件、阀门和符合规定尺寸或尺寸标准的类似零件，如第节中引用的ASME规范 2 . 1.2 对于棒材和直接由棒材或空心棒材加工而成的产品（本规范直接涉及的除外；参见 6.4 ），参见质量标准 A479/A479M , A739 ，或 A511/A511M 对于这些规范中可用的类似等级。 1.3 按照本规范制造的产品的最大重量限制为10 000磅【4540公斤】。对于较大的产品和用于其他应用的产品，请参阅规格 A336/A336M 和 A965/A965M 分别适用于类似的铁素体和奥氏体等级，可在这些规格中获得。1.4 本说明书包括几种等级的低合金钢和铁素体、马氏体、奥氏体和铁素体-奥氏体不锈钢。选择将取决于设计和服务要求。在规范中还发现了几种铁素体/奥氏体（双相）牌号 A1049/A1049M . 1.5 当需要额外的测试或检查时，提供了补充要求。这些仅适用于买方在订单中单独指定的情况。 1.6 本规范以英寸-磅单位和国际单位制单位表示。但是，除非订单规定了适用的“M”规格名称（SI单位），否则材料应按英寸-磅单位提供。 1.7 以SI单位或英寸-磅单位表示的值应单独视为标准。在正文中，国际单位制单位显示在括号中。每个系统中陈述的值可能不完全等同；因此，每个系统应独立使用。合并两个系统的值可能导致不符合标准。 1.8 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》中确立的国际公认的标准化原则制定的。

1.1 This specification 2 covers forged low alloy and stainless steel piping components for use in pressure systems. Included are flanges, fittings, valves, and similar parts to specified dimensions or to dimensional standards, such as the ASME specifications that are referenced in Section 2 . 1.2 For bars and products machined directly from bar or hollow bar (other than those directly addressed by this specification; see 6.4 ), refer to Specifications A479/A479M , A739 , or A511/A511M for the similar grades available in those specifications. 1.3 Products made to this specification are limited to a maximum weight of 10 000 lb [4540 kg]. For larger products and products for other applications, refer to Specifications A336/A336M and A965/A965M for the similar ferritic and austenitic grades, respectively, available in those specifications. 1.4 Several grades of low alloy steels and ferritic, martensitic, austenitic, and ferritic-austenitic stainless steels are included in this specification. Selection will depend upon design and service requirements. Several of the ferritic/austenitic (duplex) grades are also found in Specification A1049/A1049M . 1.5 Supplementary requirements are provided for use when additional testing or inspection is desired. These shall apply only when specified individually by the purchaser in the order. 1.6 This specification is expressed in both inch-pound units and in SI units. However, unless the order specifies the applicable “M” specification designation (SI units), the material shall be furnished to inch-pound units. 1.7 The values stated in either SI units or inch-pound units are to be regarded separately as the standard. Within the text, the SI units are shown in brackets. The values stated in each system may not be exact equivalents; therefore, each system shall be used independently of the other. Combining values from the two systems may result in non-conformance with the standard. 1.8 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.