GBT 3077-1999 合金结构钢技术条件(英文版).doc

ICS 77.140.20 H 40 NATIONAL STANDARD OF PEOPLE’S REPUBLIC OF CHINA GB/T 3077-1999 Alloy structure steels Issued on 11/01/1999 Implemented on 08/01/2000 Issued by the National Quality & Technical Supervision Bureau NATIONAL STANDARD OF PEOPLE’S REPBLIC OF CHINA GB/T 3077-1999 Alloy structure steels instead of GB/T 3077-1988 1 SCOPE This standard defines size, shape, weight and allowable tolerance, technical requirement, test method, check and acceptance regulations, packing, mark and quality certificate etc. of hot-rolled and forged alloy structure steels. This standard is suitable for alloy structure steel bars with diameters or thickness not larger than 250 mm. Those steel bars with diameters or thickness larger than 250 mm can also be supplied after negotiation by both supplier and customer The chemical content of brands defined by this standard is also suitable for steel ingot, billet and their products. 2 APPLICABLE DOCUMENTS GB/T 222-1984 Sampling method for analysis of chemical content of steel and allowable tolerance of chemical content of end product GB/T 224-1984 Measuring method of depth of decarbonizing layer of steel GB/T 225-1988 Test method of quench of hardenability end of steel GB/T 226-1991 Acid-etching check method of low power organization and defect of steel GB/T 228-1987 Test method of tension of metal GB/T 229-1994 Test method of Charpy shock of metal (U-shape notch) GB/T 231-1984 Test method of Brinell Hardness of metal GB/T 233-1982 Test method of upset forging of metal GB/T 702-1986 Size, shape, weight and allowable tolerance of hot-rolled round and square steel GB/T 908-1987 Size, shape, weight and allowable tolerance of forged round and square steel GB/T 1979-1980 Graded scheme of low power organization and defects of structured steel GB/T 2101-1989 General stipulations for check and acceptance, packing, mark and quality certificate of profiled steel GB/T 2975-1998 Sampling location and sample making of mechanics feature test of steels and steel product GB/T 4336-1984 Photoelectric emission spectrum analysis method of carbon steel and middle and low alloy steel GB/T 6397-1986 Test sample of tension of metal GB/T 7736-1987 Supersonic check and acceptance method of low power organization and defects of steel GB/T 10561-1989 Microscopic appraisal method of non-metal inclusion in steels GB/T 13299-1991 Microscopic organization appraisal method of steel GB/T 15711-1995 Acid-etching check and acceptance method of tower hair crack of steels GB/T 17505-1998 General technical conditions of delivery of steel and steel product GB/T 17616-1998 Unified digit code of brands of steel iron and alloy products YB/T 5148-1993 Measuring method of average grain-size of metal Cited standards of chemical analysis method of various elements in steel are shown on Appendix A (Appendix of Standard) 3 CONTENTS OF ORDER Contract or order according to this standard should cover following items: a) Standard numbering; b) Name of product; c) Brand or unified digit code; d) Controlled remaining elements (see 6.1.1.2 if needed); e) Weight (quantity) of delivery; f) Sizes and shape; g) Processing method; h) Delivery state; i) Delivery in heat treatment state (see 6.4 if needed); j) Hot upset forging (see 6.7 if needed); k) Decarbonizing layer (see 6.8 if needed); l) Non-metal inclusion (see 6.9 if needed); m) Special requirement (see 6.10 if needed). 4 CLASSIFICATION AND CODE 4.1 Steels are divided into three categories depending on metallurgical quality as follows: a) Top-quality steel; b) High grade top-quality steel (add “A” after brand); c) Special top-quality steel (add “E” after brand). 4.2 Steels are divided into two categories depending on usage and processing. Usage and processing methods of steels should be noted in contract. Those without notation should be referred as steel used for cutting processing. a) Steel used for press processing UP 1) Hot press processing UHP 2) Steel for upset forging UF 3) Billet for cold drawing UCD b) Steel used for cutting processing UC 5 SIZE, SHAPE, WEIGHT AND ALLOWABLE TOLERANCE 5.1 Sizes, shapes, weight and allowable tolerance of hot-rolled round and square steels should be in accord with stipulations of GB/T 702. Detailed requirements should be noted in contract. 5.2 Sizes, shapes, weight and allowable tolerance of forged round and square steels should be in accord with stipulations of GB/T 908. Detailed requirements should be noted in contract. 5.3 Sizes, shapes, weight and allowable tolerance of other sec