GB/T 3273-2026Hot rolled steel sheet and strip for automobile frames (English PDF)

1 Scope

GB/T 3273-2026 is the Chinese national standard covering the steel of a truck chassis rail - high strength, formable enough to be pressed into a deep channel section, and weldable, in the thicknesses a commercial vehicle frame is built from. It replaces GB/T 3273-2015 and has been in force since 1 October 2026. It was issued on 31 March 2026 and takes effect on 1 October 2026, replacing GB/T 3273-2015. 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, codes, notations for designations, ordering details, manufacturing process, technical requirements, test methods, inspection rules, packaging, marking, and quality certificate for hot-rolled steel plates and strips used in automobile frame. This Document applies to hot-rolled steel plates and strips (hereinafter referred to as "plates and strips") with a thickness not exceeding

18.0 mm used in the manufacture of longitudinal and transverse beams of automobile frames.

2 Normative References

The provisions in following documents become the essential provisions of this Document through reference in this Document. For the dated documents, only the versions with the dates indicated are applicable to this Document; for the undated documents, only the latest version (including all the amendments) is applicable to this Document.

GB/T 222 Steel and alloy - Permissible tolerances for chemical composition of finished products

GB/T 223 (all parts) Iron, Steel and Alloy - Methods for Chemical Analysis

GB/T 228.1 Metallic materials - Tensile testing - Part

3 Terms and Definitions

For the purposes of this Document, the terms and definitions given in YB/T 6145 apply.

5 Ordering Details

5.1 Contracts or orders placed in accordance with this Document shall include at least the following.

a) This Document number;

b) Product name;

d) Surface treatment method and surface quality grade;

e) Delivery weight (or quantity);

f) Dimensions, shape, and permissible deviations;

g) Delivery condition;

h) Edge condition;

i) Thickness accuracy;

j) Special requirements (see 7.6).

5.2 If the surface treatment method is not specified in the order contract, the product shall be delivered with a rolled surface. For hot-rolled steel plates and strips delivered with a rolled surface, if the thickness accuracy is not specified, the product shall be delivered with a general thickness accuracy. If the edge condition is not specified, steel strips shall be delivered with mill edge; and steel plates shall be delivered with cut edge. For hot-rolled steel plates and strips delivered with acid pickling surface, if the thickness accuracy, edge condition, and surface quality grade are not specified, and whether oiling or not, they shall be delivered with high- grade thickness accuracy, cut edge, general surface quality grade, and oiling. For hot-rolled steel plates and strips with eco pickled surface, ordering requirements shall comply with the provisions of YB/T 6145.

6 Manufacturing Process

6.1 Smelting method Steel is smelted in a converter or electric arc furnace. For steel plates and strips with a strength of 550L and above, vacuum degassing should be recommended.