High Strength Structural Steel Plates Q690C/D/E/F
GB/T 16270—2009 Fully Compliant | Quenched & Tempered delivery | Thickness ≤150mm | Quality grades C / D / E / F
This document specifies the designation, dimensions, shape, weight and tolerances, technical requirements, test methods, inspection rules, packaging, marking and quality certificate of high strength structural steel plates. This document applies to steel plates with thickness not greater than 150 mm delivered in quenched and tempered condition (quenching + tempering).
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.
| No. | Standard No. | Title |
|---|---|---|
| 1 | GB/T 222 | Permissible tolerances of chemical composition for finished steel |
| 2 | GB/T 223.5 | Reduced silicomolybdic complex photometric method for acid-soluble silicon content |
| 3 | GB/T 223.9 | Chrome azurol S spectrophotometric method for aluminum content |
| 4 | GB/T 223.11 | Ammonium persulfate oxidation volumetric method for chromium content |
| 5 | GB/T 223.14 | Molybdenum reagent extraction photometric method for molybdenum content |
| 6 | GB/T 223.16 | Chromotropic acid photometric method for titanium content |
| 7 | GB/T 223.17 | Diantipyrylmethane photometric method for titanium content |
| 8 | GB/T 223.19 | Neocuproine-chloroform extraction photometric method for copper content |
| 9 | GB/T 223.23 | Dimethylglyoxime spectrophotometric method for nickel content |
| 10 | GB/T 223.26 | Thiocyanate spectrophotometric method for molybdenum content |
| 11 | GB/T 223.40 | Chlorosulfophenol S spectrophotometric method for molybdenum content |
| 12 | GB/T 223.53 | Flame atomic absorption spectrometric method for copper content |
| 13 | GB/T 223.54 | Flame atomic absorption spectrometric method for nickel content |
| 14 | GB/T 223.58 | Sodium arsenite-sodium nitrite titrimetric method for manganese content |
| 15 | GB/T 223.59 | Antimony phosphomolybdate blue photometric method for phosphorus content |
| 16 | GB/T 223.60 | Perchloric acid dehydration gravimetric method for silicon content |
| 17 | GB/T 223.62 | Butyl acetate extraction photometric method for phosphorus content |
| 18 | GB/T 223.63 | Sodium periodate photometric method for manganese content |
| 19 | GB/T 223.64 | Flame atomic absorption spectrometric method for manganese content |
| 20 | GB/T 223.68 | Potassium iodate titration method after combustion in tube furnace for sulfur |
| 21 | GB/T 223.69 | Gas volumetric method after combustion in tube furnace for carbon |
| 22 | GB/T 223.76 | Flame atomic absorption spectrometric method for vanadium content |
| 23 | GB/T 223.78 | Curcumin direct photometric method for boron content |
| 24 | GB/T 228 | Metallic materials - Tensile testing at ambient temperature |
| 25 | GB/T 229 | Metallic materials - Charpy pendulum impact test method |
| 26 | GB/T 247 | General rules of packaging, marking and quality certificate |
| 27 | GB/T 709 | Dimensions, shape, weight and tolerances for hot-rolled plates |
| 28 | GB/T 2970 | Ultrasonic testing method for thick steel plates |
| 29 | GB/T 2975 | Location and preparation of samples for mechanical testing |
| 30 | GB/T 4336 | Spark discharge atomic emission spectrometric method for carbon & low-alloy steel |
| 31 | GB/T 14977 | General requirements for surface quality of hot-rolled steel plates |
| 32 | GB/T 17505 | General technical delivery requirements for steel and steel products |
| 33 | GB/T 20066 | Sampling and preparation of samples for chemical composition |
| 34 | GB/T 20123 | Infrared absorption after combustion in high-frequency furnace (total C&S) |
| 35 | GB/T 20125 | Determination of multi-element content - ICP-AES |
| 36 | GB/T 20126 | Determination of low carbon content - Infrared absorption after induction furnace combustion |
| 37 | YB/T 081 | Rounding rule and determination principle for metallurgical standard values |
The designation consists of: the Chinese Pinyin initial letter for yield strength, the specified minimum yield strength value, and the quality grade symbol (C, D, E, F).
Example: Q690E — Q: initial letter of "Qu" (yield strength); 690: minimum yield strength (MPa); E: quality grade symbol.
When ordering, the user shall provide: a) document number; b) designation; c) dimensions; d) delivery condition; e) edge condition; f) weight; g) application; h) other requirements.
5.1 The dimensions, shape, weight and tolerances shall comply with GB/T 709.
5.2 Other dimensions, shape and tolerances may be supplied by agreement between supplier and buyer.
6.1.1 The designation, chemical composition (ladle analysis) and carbon equivalent CEV shall comply with Table 1.
6.1.2 Upon agreement between supplier and buyer and indicated in the contract, carbon equivalent CET may be supplied: CET = C+(Mn+Mo)/10+(Cr+Cu)/20+Ni/40.
6.1.3 Permissible tolerances for finished chemical composition shall comply with GB/T 222.
| Grade | Chemical composition (mass fraction) / % max | CEV max | ||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| C | Si | Mn | P | S | Cu | Cr | Ni | Mo | B | V | Nb | Ti | ≤50 | >50~100 | >100~150 | |
| Q690C | 0.20 | 0.80 | 1.80 | 0.025 | 0.015 | 0.50 | 1.50 | 2.00 | 0.70 | 0.005 | 0.12 | 0.06 | 0.05 | 0.65 | 0.77 | 0.83 |
| Q690D | 0.20 | 0.80 | 1.80 | 0.025 | 0.015 | 0.50 | 1.50 | 2.00 | 0.70 | 0.005 | 0.12 | 0.06 | 0.05 | 0.65 | 0.77 | 0.83 |
| Q690E | 0.20 | 0.80 | 1.80 | 0.020 | 0.010 | 0.50 | 1.50 | 2.00 | 0.70 | 0.005 | 0.12 | 0.06 | 0.05 | 0.65 | 0.77 | 0.83 |
| Q690F | 0.20 | 0.80 | 1.80 | 0.020 | 0.010 | 0.50 | 1.50 | 2.00 | 0.70 | 0.005 | 0.12 | 0.06 | 0.05 | 0.65 | 0.77 | 0.83 |
NOTE a The values for Cu, Cr, Ni, Mo are maximum. For quenched and tempered steel, B content ≤0.0005% and H ≤0.0002% if applicable.
NOTE b CEV formula: CEV = C + Mn/6 + (Cr+Mo+V)/5 + (Ni+Cu)/15.
NOTE c Residual elements B and H may be omitted if guaranteed by the supplier.
6.2 Steel shall be made by converter or electric arc furnace.
6.3 Plates shall be delivered in quenched and tempered condition (quenching + tempering).
6.4.1 The mechanical properties and process performance shall comply with Table 2.
6.4.2 Charpy impact energy shall be calculated as arithmetic mean of three specimens; one individual value may be lower than specified value but not less than 70% of the specified value.
| Grade | Yield strength ReH/MPa (min) | Tensile strength Rm/MPa | A% (min) | Impact energy KV₂/J (longitudinal) min | |||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
| ≤50 | >50~100 | >100~150 | ≤50 | >50~100 | >100~150 | 0℃ | -20℃ | -40℃ | -60℃ | ||
| Q690C | 690 | 650 | 630 | 770~940 |
760~930 | 710~900 | 14 | 47 | — | — | — |
| Q690D | 14 | — | 47 | — | — | ||||||
| Q690E | 14 | — | — | 34 | — | ||||||
| Q690F | 14 | — | — | — | 34 | ||||||
NOTE a For thickness >100~150mm, tensile strength and impact values may be subject to agreement between supplier and buyer.
NOTE b Subsized impact specimens for thickness <12mm as per 6.4.3: 8~12mm → 7.5×10×55mm result ≥75% of specified value; 6~8mm → 5×10×55mm result ≥50%; no impact test for thickness <6mm.
6.5.1 The plate surface shall be free from cracks, blisters, scabs, folds, inclusions and delamination. Cleaning depth ≤ half thickness tolerance.
6.5.2 Other defects depth ≤ half thickness tolerance.
6.5.3 Welding repair permitted by agreement; if repaired after quenching & tempering, retreatment required.
6.5.4 By agreement, surface quality may comply with GB/T 14977.
6.6.1 By agreement, ultrasonic testing per plate per GB/T 2970 (acceptance level to be specified).
6.6.2 Other special requirements may be agreed.
7.1 The inspection items, number of specimens, sampling method and test methods for each batch shall comply with Table 3.
| No. | Inspection Item | Number of samples | Sampling method | Test method |
|---|---|---|---|---|
| 1 | Chemical analysis | 1 per heat | GB/T 20066 | GB/T 223, GB/T 4336, etc. |
| 2 | Tensile test | 1 | GB/T 2975 | GB/T 228 |
| 3 | Impact test | 3 | GB/T 2975 | GB/T 229 |
| 4 | Non-destructive testing | each plate | per standard | GB/T 2970 |
7.2 Visual inspection for surface condition. For arbitration of chemical composition, use GB/T 223.
NOTE a For chemical analysis arbitration, test methods according to GB/T 223 series.
8.1 Inspection and acceptance by supplier's quality inspection department; buyer may perform any check.
8.2 Batch acceptance: same heat, same designation, same heat treatment, thickness difference ≤5mm, batch weight ≤60t.
8.3 If impact test fails, retest with three additional specimens; average of six specimens ≥ specified value; only one specimen may be <70% of specified value.
8.4 Re-inspection and judgment per GB/T 17505.
Shall comply with GB/T 247.
Shall comply with YB/T 081.
| This Standard GB/T 16270-2009 | GB/T 16270-1996 | EN10025-6:2004(E) | ISO 4950.3-2003 |
|---|---|---|---|
| Q690C | — | — | — |
| Q690D | Q690QD | S690Q | — |
| Q690E | Q690QE | S690QL | E690DD |
| Q690F | — | S690QL1 | E690E |
🔗 Q690C Product Page 🔗 Q690D Product Page 🔗 Q690E Product Page 🔗 Q690F Product Page