GB/T 11251-2025Alloy structural steel plate, sheet and strip (English PDF)

1 Scope

This document specifies the ordering details, manufacturing process, technical requirements, test methods, inspection rules, packaging, marking, and quality certificates for alloy structural steel plate/sheet and strip.

This document applies to single-sheet hot-rolled steel plate/sheet with a nominal thickness of 3.0 mm ~ 250 mm (hereinafter referred to as single-rolled steel plate/sheet); hot-continuously-rolled steel plate/sheet and strip with a nominal thickness not greater than 25.4 mm, including hot-continuously-rolled wide steel strip, sheared steel plate/sheet, and slit steel strip with a nominal width not less than 600 mm, and hot-continuously-rolled narrow steel strip and sheared steel plate/sheet with a nominal width less than 600 mm (hereinafter referred to as steel plate/sheet and strip).

NOTE: Single-rolled steel plate/sheet, steel plate/sheet and strip are collectively referred to as steel products in this document.

2 Normative references

The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies.

GB/T 222 Steels and alloys - Permissible deviations of product analyzed chemical composition

GB/T 223 (all parts) Methods for chemical analysis of iron, steel and alloy

GB/T 224 Determination of the depth of decarburization of steels

GB/T 228.1 Metallic materials - Tensile testing - Part 1: Method of test at room temperature

GB/T 229 Metallic materials - Charpy pendulum impact test method

GB/T 231.1 Metallic materials - Brinell hardness test - Part 1: Test method

GB/T 232 Metallic materials - Bend testing method

GB/T 247 General rule of package, mark and certification for steel plates (sheets) and strips

GB/T 709-2019 Dimension, shape, weight and tolerance for hot-rolled steel strip, plate and sheet

GB/T 2970-2016 Method for ultrasonic testing of thicker steel plates

GB/T 2975 Steel and steel products - Location and preparation of samples and test pieces for mechanical testing

GB/T 3077 Alloy structure steels

GB/T 4336 Carbon and low-alloy steel - Determination of multi-element contents - Spark discharge atomic emission spectrometric method (routine method)

GB/T 8170 Rules of rounding off for numerical values & expression and judgement of limiting values

GB/T 10561-2023 Determination of content of nonmetallic inclusions in steel - Micrographic method using standard diagrams

GB/T 11261 Steel and iron - Determination of oxygen content - The pulse heating inert gas fusion-infra-red absorption method

GB/T 17505 Steel and steel products - General technical delivery requirements

GB/T 20066 Steel and iron - Sampling and preparation of samples for the determination of chemical composition

GB/T 20123 Steel and iron - Determination of total carbon and sulfur content - Infrared absorption method after combustion in an induction furnace (routine method)

GB/T 20124 Steel and iron - Determination of nitrogen content - Thermal conductimetric method after fusion in a current of inert gas (routine method)

GB/T 34474.1-2017 Determination of banded structure of steel - Part 1: Micrographic method using standards diagrams

3 Terms and definitions

For the purpose of this document, the terms and definitions defined in GB/T 709-2019 apply.

4 Ordering details

A contract or order placed according to this document shall include the following:

a) serial number of this document;

b) product name;

c) designation;

d) dimensions, shape, and tolerance or thickness accuracy;

e) delivery weight (or quantity);

f) delivery condition;

g) edge condition;

h) surface treatment and surface quality grade;

i) processing purpose (if for stamping, this shall be specified);

j) special requirements.

5 Manufacturing process

6 Technical requirements