【国外标准】 Standard Specification for Steel Forgings, Carbon and Alloy, for Pinions, Gears and Shafts for Reduction Gears

This specification covers normalized and tempered carbon steel, and liquid quenched and tempered alloy steel forgings for pinions, gears, and shafts for reduction gears. Prior to heat treatment for mechanical properties testing , steel materials may undergo machining and boring, after which specimens shall be stress relieved. Tensile, impact and Brinell hardness tests shall be performed wherein forgings shall conform to the following mechanical properties: tensile strength, yield strength, elongation, reduction of area, Charpy V-notch, and Brinell hardness. Specimens shall also conform to chemical requirements for carbon, manganese, phosphorus, sulfur, silicon, nickel, chromium, molybdenum, vanadium, copper, and aluminum.1.1 This specification covers normalized and tempered carbon steel and quenched and tempered alloy steel forgings for pinions, gears, and shafts.1.2 Several grades of steel are covered as follows:1.2.1 Grade 1, Class A,  is normalized and tempered carbon steel.1.2.2 Grade 2, Class B, Grade 3, Class C, Grade 3A, Class D, Grades 4 to 7, Classes E, F, G, and H, Grade 8, Class I, and Grade 9, Class J,  are liquid quenched and tempered alloy steel.1.3 All grades and classes are considered weldable under proper conditions. Welding technique is of fundamental importance and it is presupposed that welding procedure and inspection shall be in accordance with approved methods for the class of material used.1.4 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.1.5 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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.1.6 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.