【国外标准】 Standard Specification for High-Strength Steel Castings in Heavy Sections

This specification covers cast alloy steels in the normalized and tempered or quenched and tempered condition, suitable for high strain gradient conditions. One test block for each heat is required. The test block configuration and size are specified. Tension and Charpy impact tests and oxygen, nitrogen, and hydrogen gas content tests shall be performed. The steel shall be made by electric furnace process with methods, such as argon-oxygen-decarburization, to conform to the maximum gas level. Heat treatment procedure shall be done. Multiple austenitizing and tempering are permitted. The chemistry grade shall conform to the required chemical composition for carbon, manganese, phosphorus, sulfur, silicon, nickel, chromium, molybdenum, and aluminum. Residual elements include: zirconium, copper, titanium, tungsten, vanadium, columbium, and boron. A product analysis shall be made for specification conformance. Casting shell and core depth zone shall be established and examined. Repair methods such as grinding and welding are detailed.1.1 This specification covers cast alloy steels in the normalized and tempered or quenched and tempered condition, in section sizes through 37 in. (940 mm), suitable for high-strain gradient conditions such as those encountered in hooks, shackles, support frames, and other lifting devices. The classes of steel in this specification are weldable only with qualified procedures.1.2 Section range and class selection will depend on design and service conditions. Users should note that this specification contemplates mechanical property gradients.1.3 The values stated in inch-pound units or SI units are to be regarded separately as standard. Within the text, the SI units are shown in parentheses. The values stated in each system are not exact equivalents; therefore, each system must be used independently of the other. Combining values from the two systems may result in nonconformance with the specification. Inch-pound units are applicable for material ordered to this specification and SI units for material ordered to this specification.1.4 If, by agreement, castings are to be supplied in a partially completed condition, that is, all of the provisions of the product specification have not been filled, then the material marking (see Section 15) and certification (see Section 14) are to reflect the extent to which the product specification requirements have been met.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.