1.1 本规范涵盖压力管道应用的锻造不锈钢配件。 2 1.2 本规范中包括几种等级的奥氏体不锈钢合金。根据适用的ASME或MSS尺寸和等级标准，等级分别用前缀WP或CR表示。 1.3 对于每个WP不锈钢等级，涵盖了几类配件，以表明是采用无缝结构还是焊接结构。类别名称还用于指示无损检测方法和无损检测(NDE)的范围。 表1 是适用于本规范涵盖的所有WP等级不锈钢的配件等级的一般总结。CR等级没有课程。其他地方涵盖了具体要求。1.4 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。 1.5 以SI单位或英寸-磅单位表示的值应单独视为标准值。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。 1.6 本规范不适用于铸钢配件。规范中涵盖了奥氏体不锈钢铸件 A351M , A743/A743M ，和 A744/A744M . 1.7 本国际标准是根据《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世界贸易组织技术性贸易壁垒（TBT）委员会发布的数据。

1.1 This specification covers wrought stainless steel fittings for pressure piping applications. 2 1.2 Several grades of austenitic stainless steel alloys are included in this specification Grades are designated with a prefix, WP or CR, based on the applicable ASME or MSS dimensional and rating standards, respectively. 1.3 For each of the WP stainless grades, several classes of fittings are covered, to indicate whether seamless or welded construction was utilized. Class designations are also utilized to indicate the nondestructive test method and extent of nondestructive examination (NDE). Table 1 is a general summary of the fitting classes applicable to all WP grades of stainless steel covered by this specification. There are no classes for the CR grades. Specific requirements are covered elsewhere. 1.4 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. 1.5 The values stated in either SI units or inch-pound units are to be regarded separately as 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. 1.6 This specification does not apply to cast steel fittings. Austenitic stainless steel castings are covered in Specifications A351/A351M , A743/A743M , and A744/A744M . 1.7 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.