GB/T 702-2026Steel bars - Dimensions, shape, weight and tolerances (English PDF)

Foreword

This document was drafted in accordance with the rules provided in GB/T 1.1-2020 Directives for Standardization - Part

1.Rules for the Structure and Drafting of Standardizing Documents. This document serves as a replacement for GB/T 702-2017 Hot-rolled Steel Bars - Dimensions, Shape, Weight and Tolerances, GB/T 908-2019 Forged Bars for Dimensions, Shape, Weight and Tolerances and GB/T 905-1994 Dimension, Shape, Weight and Tolerance for Cold-drawn Round, Square and Hexagonal Steels. This document is based on GB/T 702-2017 and integrates the contents of GB/T 908-2019 and GB/T 905-1994.In comparison with GB/T 702-2017, apart from structural adjustments and editorial modifications, the main technical changes are as follows:

---The dimension range for hot-rolled round steel is modified, and the dimension ranges for forged steel bars and cold-drawn steel bars are added (see Chapter 1; Chapter 1 of Version 2017);

---Classification is added (see Chapter 4);

---The permissible dimensional deviations for hot-rolled round steel are modified (see Table 1; Table 1 of Version 2017);

---The cross-sectional views, cross-sectional dimensions, weight and permissible deviations, length and permissible deviations, and shapes for forged steel bars and cold- drawn steel bars are added (see Chapter 5, Chapter 6, Chapter 7 and Chapter 8);

---The curvature requirements for hot-rolled flat steel are modified (see

8.2.1 and Table 17;

5.2 and Table 11 of Version 2017). Please be noted that certain content of this document may involve patents. The institution issuing this document does not undertake the responsibility of identifying these patents. This document was proposed by China Iron & Steel Association. This document shall be under the jurisdiction of National Technical Committee 183 on Steel of Standardization Administration of China (SAC/TC 183). The drafting organizations of this document. Jiangyin Xingcheng Special Steel Co., Ltd.; Fushun Special Steel Co., Ltd.; Daye Special Steel Co., Ltd.; Shandong Jiu Yang Group Co., Ltd.; China Metallurgical Information and Standardization Institute; Wuxi Tianchen Cold Drawn Steel Co., Ltd.; Jiangsu Tri-m Special Metals Co., Ltd. The main drafters of this document. Wu Xiaolin, Gu Qiang, Chen Qinghua, Zhang Yue, Wang Yujie, Xu Bozhang, Meng Yu, Zhai Jun, Liu Baoshi, Ou Rong, Han Huaibin, Jiang Nan, Yu Lei, Xu Haochi, Zhou Xingliang, Yang Xiyao, Wang Lei. The issuing of the previous versions. Dimensions, Shape, Weight and Tolerances of Steel Bars

1 Scope

GB/T 702-2026 is the Chinese national standard covering the dimensional standard for hot rolled steel bar - round, square, hexagonal and flat, with the tolerances, the straightness and out-of-round limits and the mass per metre by which bar is bought. It replaces GB/T 702-2017 and has been in force since 1 November 2026, alongside the section and flat product dimension standards revised in the same period. It was issued on 30 April 2026 and takes effect on 1 November 2026, replacing GB/T 702-2017. The document is under the responsibility of the China Iron and Steel Association. This page is published from the official record of the 2026 edition; the clause text of a standard this recent is not yet in circulation, and the figures, limits and tables it contains are those of the document itself, delivered in full with the English translation.

This document specifies the classification, cross-sectional shape, cross-sectional dimensions, weight and permissible deviations, length and permissible deviations, and shape of hot-rolled steel bars (round steel, square steel, flat steel, hexagonal steel and octagonal steel), forged steel bars (round steel, square steel and flat steel), and cold-drawn steel bars (round steel, square steel and hexagonal steel). This document applies to hot-rolled round steel with a nominal diameter of

5.5 mm to 400 mm and hot-rolled square steel with a side length of

5.5 mm to 300 mm; general-purpose hot-rolled flat steel with a thickness of 3 mm to 60 mm and a width of 10 mm to 200 mm; hot-rolled tool and die steel flat steel with a thickness of 4 mm to 100 mm and a width of 10 mm to 310 mm (general-purpose hot-rolled flat steel and hot-rolled tool and die steel flat steel are hereinafter collectively referred to as hot-rolled flat steel); hot-rolled hexagonal steel with an opposite-side distance of 8 mm to 70 mm and hot-rolled octagonal steel with an opposite-side distance of 16 mm to 40 mm. This document applies to forged round steel with a nominal diameter of 40 mm to 1,300 mm, forged square steel with a side length of 40 mm to 1,000 mm, and forged flat steel with a thickness of 20 mm to 800 mm and a width of 40 mm to 1,500 mm. This document applies to cold-drawn round steel, square steel, and hexagonal steel with a nominal dimension of 3 mm to 80 mm. Corrosion-resistant alloy and high-temperature alloy bars may refer to this document for further details.

2 Normative References

This document does not have normative references.

3 Terms and Definitions

This document does not have terms or definitions that need to be defined.

4 Classification

Steel bars are classified into the following four categories in accordance with their surface condition upon delivery.

a) Hot-rolled/hot-forged steel bars. commonly known as "black skin", delivered with

6.1.1.5 Upon negotiation between the supply-side and the demand-side, and as specified in the contract, other dimensions of hot-rolled steel bars not specified in Table A.1 to Table A.4 may also be supplied.

6.1.1.6 Hot-rolled steel bars should preferably be delivered by actual weight. Upon negotiation between the supply-side and the demand-side, and as specified in the contract, delivery by theoretical weight is also permissible.

6 Cross-sectional Dimensions, Weight and Permissible Deviations...