1.1 本规范 2 涵盖用于低温服务的压力容器、阀门、法兰和配件的合金和不锈钢螺栓材料和螺栓部件。参见质量标准 A962/A962M 螺栓连接的定义。棒材应热锻，并可通过无心磨削或冷拔进一步加工。奥氏体不锈钢可以固溶退火或退火和应变硬化。订购应变硬化奥氏体不锈钢时，买方应特别注意确保 附录X1 是完全理解的。 1.2 涵盖了几个等级，包括铁素体钢和奥氏体钢，编号为L7、B8等。选择将取决于设计、使用条件、机械性能和低温特性。的机械要求 表1 指出最小机械性能适用于各种等级和等级的直径，以及 表2 规定了夏比冲击能量吸收的要求。制造商应在制造零件之前确定材料能够符合这些要求。例如，当等级L43被指定为满足 表2 对于−150°F[−101°C]的冲击能量值，AISI 4340的化学成分可能需要额外的限制（例如采购磷和硫含量低于正常供应的钢）。 附注1: 制定本规范的委员会包括了几个等级的材料，这些材料已经相当广泛地用于本目的。随着需要变得明显，委员会将不时考虑纳入其他组成。用户应注意，所提及的一些牌号的淬透性可能会限制可获得所需机械性能的最大尺寸。 1.3 以下引用的一般要求对于本规范的应用是必不可少的: A962/A962M . 1.4 与螺栓连接一起使用的螺母包含在第节中 10 并对螺母材料进行冲击试验。 1.5 提供补充要求供买方选择使用。补充要求仅在定购单或合同中规定时适用。 1.6 本规范以英寸-磅单位和国际单位制单位表示；但是，除非采购订单或合同规定了适用的 米 规格名称（SI）单位，应适用英寸-磅单位。 1.7 以SI单位或英寸-磅单位表示的值应单独视为标准值。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 alloy and stainless steel bolting materials and bolting components for pressure vessels, valves, flanges, and fittings for low-temperature service. See Specification A962/A962M for the definition of bolting. The bars shall be hot-wrought and may be further processed by centerless grinding or by cold drawing. Austenitic stainless steel may be solution annealed or annealed and strain-hardened. When strain hardened austenitic stainless steel is ordered, the purchaser should take special care to ensure that Appendix X1 is thoroughly understood. 1.2 Several grades are covered, including both ferritic and austenitic steels designated L7, B8, etc. Selection will depend on design, service conditions, mechanical properties, and low-temperature characteristics. The mechanical requirements of Table 1 indicate the diameters for which the minimum mechanical properties apply to the various grades and classes, and Table 2 stipulates the requirements for Charpy impact energy absorption. The manufacturer should determine that the material can conform to these requirements before parts are manufactured. For example, when Grade L43 is specified to meet the Table 2 impact energy values at −150 °F [−101 °C], additional restrictions (such as procuring a steel with lower P and S contents than might normally be supplied) in the chemical composition for AISI 4340 are likely to be required. Note 1: The committee formulating this specification has included several grades of material that have been rather extensively used for the present purpose. Other compositions will be considered for inclusion by the committee from time to time as the need becomes apparent. Users should note that hardenability of some of the grades mentioned may restrict the maximum size at which the required mechanical properties are obtainable. 1.3 The following referenced general requirements are indispensable for application of this specification: Specification A962/A962M . 1.4 Nuts for use with bolting are covered in Section 10 and the nut material shall be impact tested. 1.5 Supplementary Requirements are provided for use at the option of the purchaser. The supplementary requirements shall apply only when specified in the purchase order or contract. 1.6 This specification is expressed in both inch-pound units and SI units; however, unless the purchase order or contract specifies the applicable M specification designation (SI) units, the inch-pound units shall apply. 1.7 The values stated in either SI units or inch-pound units are to be regarded separately as standard. 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.