This standard is developed in accordance with the rules given in GB/T 1.1-2020 Directives for standardization - Part 1: Rules for the structure and drafting of standardizing documents.
This document replaces GB/T 28905-2012 Low yield strength steel plates for construction. In addition to structural adjustments and editorial changes, the following main technical changes have been made with respect GB/T 28905-2012:
a) The maximum thickness of steel plate has been changed to 120 mm and the coil-cut steel plate with a thickness not greater than 25.4 mm has been added (see Clause 1 hereof; Clause 1 of 2012 edition);
b) The designation of LY300 and its corresponding technical requirements have been added (see Tables 1 and 2 hereof);
c) The chemical composition regulations of C and P have been changed, and the regulations that the intentional addition of alloying elements shall be indicated in the quality certificate have been added (see Table 1 hereof; Table 1 of 2012 edition);
d) The requirement that delivery may be made in other conditions after negotiation between the supplier and the supplier has been added to the delivery state (see 7.3 hereof; 7.3 of 2012 edition);
e) The requirements for the yield ratio of designations LY160 and LY225 have been changed (see Table 2 hereof; Table 2 of 2012 edition);
f) The requirements that surface defects of steel plates are allowed to be removed by grinding and other methods and repair welding is not allowed have been added (see 7.5.3 and 7.5.4 hereof);
g) The requirement for the minimum thickness of thickness direction performance has been changed (see 7.6.3 hereof; 6.6.2 of 2012 edition);
h) Special requirements for bending test, grain size and non-metallic inclusions have been added (see 7.6.2, 7.6.5 hereof);
i) The requirements for inspection lots have been changed (see 9.2 hereof, 7.2 of 2012 edition);
j) The requirements for the inspection document type have been added (see Clause 10 hereof).
Low yield strength steel plate for construction
1 Scope
This document specifies the designation expression methods, order contents, dimensions, appearance, weight, technical requirements, test methods, inspection rules, packaging, marking and quality certificate of low yield strength steel plate for construction.
This document is applicable to the manufacture of single rolled steel plates with a thickness of not more than 120 mm and coil-cut steel plates with a thickness of not more than 25.4 mm for the manufacture of energy-consuming structural elements (e.g., energy-consuming damping elements, etc.) for seismic and shock-absorbing construction.
2 Normative references
The following documents contain requirements which, through reference in this text, constitute indispensable requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 222 Permissible tolerances for chemical composition of steel products
GB/T 223.5 Steel and iron - Determination of acid-soluble silicon and total silicon content - Reduced molybdosilicate spectrophotometric method
GB/T 223.12 Methods for chemical analysis of iron, steel and alloy - The sodium carbonate separation-diphenyl carbazide photometric method for the determination of chromium content
GB/T 223.23 Iron, steel and alloy - Determination of nickel content - The dimethylglyoxime spectrophotometric method
GB/T 223.26 Iron, steel and alloy - Determination of molybdenum content - The thiocyanate spectrophotometric method
GB/T 223.37 Iron, steel and alloy - Determination of nitrogen content - Indophenol blue spectrophotometric method after distillation separation
GB/T 223.40 Iron, steel and alloy - Determination of niobium content by the sulphochlorophenol S spectrophotometric method
GB/T 223.53 Methods for chemical analysis of iron, steel and alloy - Flame atomic absorption spectrometric method for the determination of copper content
GB/T 223.54 Iron, steel and alloy - Determination of nickel content - Flame atomic absorption spectrometric method
GB/T 223.59 Iron, steel and alloy - Determination of phosphorus content - Bismuth phosphomolybdate blue spectrophotometric method and antimony phosphomolybdate blue spectrophotometric method
GB/T 223.60 Methods for chemical analysis of iron, steel and alloy - The perchloric acid dehydration gravimetric method for the determination of silicon content
GB/T 223.63 Iron, steel and alloy - Determination of manganese content - Sodium(potassium) periodate spectrophotometric method
GB/T 223.64 Iron steel and alloyed - Determination of manganese content - Flame atomic absorption spectrometric method
GB/T 223.76 Methods for chemical analysis of iron, steel and alloy - The flame atomic absorption spectrometric method for the determination of vanadium content
GB/T 223.78 Methods for chemical analysis of iron, steel and alloy - Curcumin spectrophotometric method for the determination of boron content
GB/T 223.84 Steel, iron and alloy - Determination of titanium content - Diantipyrylmethane spectrophotometric method
GB/T 223.85 Steel and iron - Determination of sulfur content - Infrared absorption method after combustion in an induction furnace
GB/T 223.86 Steel and iron - Determination of total carbon content - Infrared absorption method after combustion in an induction furnace
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 232 Metallic materials - Bend test
GB/T 247 General rule of package, mark and certification for steel plates (sheets) and strips
GB/T 709 Dimension, shape, weight and tolerance for cold-rolled steel strip and sheet
GB/T 2970 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 4336 Carbon and low-alloy steel - Determination of multi-element contents - Spark discharge atomic emission spectrometric method (routine method)
GB/ T 5313 Steel Plate with Through-thickness Characteristics
GB/T 6394 Determination of estimating the average grain size of metal
GB/T 8170 Rules of rounding off for numerical values & expression and judgment of limiting values
GB/T 10561 Steel - Determination of content of nonmetallic inclusions - Micrographic method using standards diagrams
GB/T 14977 General requirement for surface condition of hot-rolled steel plates
GB/T 17505 Steel and steel products - General technical delivery requirements
GB/T 18253-2018 Steel and steel products -Types of inspection documents
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 20125 Low-alloy steel - Determination of multi-element contents - Inductively coupled plasma atomic emission spectrometric method
GB/T 20126 Unalloyed steel - Determination of low carbon content - Part 2: Infrared absorption method after combustion in an induction furnace (with preheating)
3 Terms and definitions
No terms and definitions are listed in this standard.
4 Designation expression methods
The designation of steel consists of the first letter "LY" in the English term "Low Yield" and the specified yield strength target value.
Example: LY160
LY——the first letter "LY" in the English term "Low Yield";
160——the specified yield strength target value, MPa.
Foreword i
1 Scope
2 Normative references
3 Terms and definitions
4 Designation expression methods
5 Order contents
6 Dimensions, appearance, and weight
7 Technical requirements
8 Test methods
9 Inspection rules
10 Packaging, marking and quality certificate