【国外标准】 Standard Specification for Screws, Alloy Steel, Heat Treated, 170 ksi and 1170 MPa Minimum Tensile Strength (Inch and Metric)

This specification covers the requirements for quenched and tempered alloy steel screws 0.060 through 1 1/2 inches in diameter having a minimum ultimate tensile strength of 170 KSI. High strength screws shall be heat treated by quenching in oil from above the transformation temperature and then tempered by reheating to at least 797°F to within the hardness range. One or more of the following alloying elements: chromium, nickel, molybdenum, or vanadium shall be present in sufficient quantity to ensure that the specified strength properties are met after oil quenching and tempering. The hardness limits shall be met anywhere on the cross section through the threads, one diameter from the screw point.1.1 This specification covers the requirements for quenched and tempered alloy steel screws 0.060 through 11/2 in. and 1.6 through 48 mm in diameter having a minimum ultimate tensile strength of 170 KSI or 1170 MPa.1.2 The values are stated in inch-pound units for inch fasteners and SI metric units for metric fasteners. 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 to the standard.1.3 The following hazard caveat pertains only to the test method portion, Section 10, of this specification: 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 and health practices and determine the applicability of regulatory limitations prior to use.1.4 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.