【国外标准】 Standard Specification for Carbon and Alloy Steel Forgings for Rings for Reduction Gears

This specification deals with normalized and tempered, and quenched and tempered, carbon and alloy steel forged or rolled rings for reduction gears. The grades and classes of steels covered here are: Grade 1, Classes A and B, and Grade 2, Classes C and D, which are carbon steels; and Grade 3, Classes E and F, Grade 4, Classes G, H, I, J, K and L, Grade 5, Classes M and P, and Grade 6, Class T, which are alloy steels. Materials shall be manufactured by melting and forging processes and optional machining, and shall be allowed to cool prior to reheating. Heat treatment shall consist of normalizing and tempering for Grade 1, Classes A and B, and quenching and tempering for all other grades and classes. Heat and product analyses shall be performed wherein specimens shall conform to required chemical composition of carbon, manganese, phosphorus, sulfur, silicon, nickel, chromium, molybdenum, vanadium, copper, and aluminum. Steels shall also undergo tension, impact, and Brinell hardness tests, and shall conform to the following mechanical requirements: tensile strength, yield strength, elongation, reduction of area, Brinell hardness, and Charpy V-notch.1.1 This specification covers normalized and tempered, and quenched and tempered, carbon and alloy steel forged or rolled rings for reduction gears.1.2 Several grades and classes of steel are covered as follows:1.2.1 Grade 1, Classes A and B, and Grade 2, Classes C and D, are carbon steel.1.2.2 Grade 3, Classes E and F, Grade 4, Classes G, H, I, J, K and L, Grade 5, Classes M and P, and Grade 6, Class T, are alloy steel.1.2.3 All grades and classes are considered weldable under proper conditions. Welding techniques are of fundamental importance and it is pre-supposed that welding procedure and inspection will be in accordance with proper methods for the class of material used.1.3 The values stated in either SI units or inch-pound units are to be regarded separately as standard. The values stated in each system are not necessarily exact equivalents; therefore, to ensure conformance with the standard, each system shall be used independently of the other, and values from the two systems shall not be combined.1.4 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.1.5 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.