Q245R Pressure Vessel Steel Plate
Compliant with GB/T 713.2—2023 | Hot Rolled / Normalized Rolled / Normalizing | Boiler & Pressure Vessel Steel
1 Scope
This document specifies the designation representation method, ordering content, dimensions, shape, weight, technical requirements, test methods, inspection rules, packaging, marking and quality certificate of non-alloy and alloy steel plates and strips for pressure equipment with specified temperature properties. This document applies to steel strips and cut-to-length plates with a thickness not greater than 25.4mm and single-rolled plates with a thickness of 3mm ~ 250mm of Q245R steel for pressure equipment with service temperature not lower than -20℃.
2 Normative References
The following documents are referred to in the text in such a way that some or all of their content constitutes requirements of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the normative referenced document (including any amendments) applies.
| No. | Standard |
|---|---|
| 1 | GB/T 223.3 Iron, steel and alloy - Determination of phosphorus content |
| 2 | GB/T 223.9 Iron, steel and alloy - Determination of aluminum content |
| 3 | GB/T 223.11 Iron, steel and alloy - Determination of chromium content |
| 4 | GB/T 223.12 Methods for chemical analysis of iron, steel and alloy - Determination of chromium content |
| 5 | GB/T 223.14 Methods for chemical analysis of iron, steel and alloy - Determination of tantalum content |
| 6 | GB/T 223.17 Methods for chemical analysis of iron, steel and alloy - Determination of titanium content |
| 7 | GB/T 223.18 Methods for chemical analysis of iron, steel and alloy - Determination of copper content |
| 8 | GB/T 223.19 Methods for chemical analysis of iron, steel and alloy - Determination of copper content |
| 9 | GB/T 223.23 Iron, steel and alloy - Determination of nickel content |
| 10 | GB/T 223.26 Iron, steel and alloy - Determination of molybdenum content |
| 11 | GB/T 223.31 Iron, steel and alloy - Determination of arsenic content |
| 12 | GB/T 223.37 Iron, steel and alloy - Determination of nitrogen content |
| 13 | GB/T 223.40 Iron, steel and alloy - Determination of palladium content |
| 14 | GB/T 223.47 Methods for chemical analysis of iron, steel and alloy - Determination of antimony content |
| 15 | GB/T 223.50 Methods for chemical analysis of iron, steel and alloy - Determination of tin content |
| 16 | GB/T 223.53 Methods for chemical analysis of iron, steel and alloy - Determination of copper content |
| 17 | GB/T 223.60 Methods for chemical analysis of iron, steel and alloy - Determination of silicon content |
| 18 | GB/T 223.62 Methods for chemical analysis of iron, steel and alloy - Determination of phosphorus content |
| 19 | GB/T 223.63 Iron, steel and alloy - Determination of manganese content |
| 20 | GB/T 223.67 Iron, steel and alloy - Determination of sulfur content |
| 21 | GB/T 223.68 Methods for chemical analysis of iron, steel and alloy - Determination of sulfur content |
| 22 | GB/T 223.69 Iron, steel and alloy - Determination of carbon content |
| 23 | GB/T 223.75 Iron, steel and alloy - Determination of boron content |
| 24 | GB/T 223.76 Methods for chemical analysis of iron, steel and alloy - Determination of molybdenum content |
| 25 | GB/T 223.77 Methods for chemical analysis of iron, steel and alloy - Determination of calcium content |
| 26 | GB/T 223.78 Iron, steel and alloy - Determination of manganese and arsenic content |
| 27 | GB/T 223.82 Iron, steel and alloy - Determination of hydrogen content |
| 28 | GB/T 228.1 Metallic materials - Tensile testing - Part 1: Method of test at room temperature |
| 29 | GB/T 228.2 Metallic materials - Tensile testing - Part 2: Method of test at elevated temperature |
| 30 | GB/T 229 Metallic materials - Charpy pendulum impact test method |
| 31 | GB/T 232 Metallic materials - Bending test method |
| 32 | GB/T 713.1 Steel plate, sheet and strip for pressure equipments - Part 1: General requirements |
| 33 | GB/T 2975 Steel and steel products - Location and preparation of samples for mechanical testing |
| 34 | GB/T 4336 Carbon steel and low-alloy steel - Determination of multi-element content - Spark discharge atomic emission spectrometric method |
| 35 | GB/T 5313 Steel plates with through-thickness characteristics |
| 36 | GB/T 6803 Drop-weight tear test method for ferritic steels |
| 37 | GB/T 8650 Evaluation of pipeline and pressure vessel steels for resistance to hydrogen-induced cracking |
| 38 | GB/T 20066 Steel and iron - Sampling and preparation of samples for the determination of chemical composition |
| 39 | GB/T 20123 Steel and iron - Determination of total carbon and sulfur content |
| 40 | GB/T 20124 Steel and iron - Determination of nitrogen content |
| 41 | GB/T 20125 Low-alloy steel - Determination of multi-element content |
| 42 | NB/T 47013.3 Non-destructive testing of pressure equipments - Part 3: Ultrasonic testing |
3 Terms and Definitions
The terms and definitions defined in GB/T 713.1 apply to this document.
4 Designation Representation Method
For carbon steel and low alloy high strength steel, the designation is represented by the yield strength value and the Chinese phonetic alphabet initials of "Qu" and "Rong", e.g.: Q245R. For molybdenum steel and chromium-molybdenum steel, it is represented by the average carbon content and alloy element letters plus "R".
5 Ordering Content
The ordering content of steel plates shall comply with GB/T 713.1.
6 Dimensions, Shape, Weight
The dimensions, shape and weight of steel plates shall comply with GB/T 713.1.
7 Technical Requirements
7.1 Designation and Chemical Composition
7.1.1 The designation and chemical composition (ladle analysis) of steel shall comply with Table 1.
| Grade | C | Si | Mn | Cu | Ni | Cr | Mo | Nb | V | Ti | Alt | P | S | Other |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Q245R | ≤0.20 | ≤0.35 | 0.50~1.10 | ≤0.30 | ≤0.30 | ≤0.30 | ≤0.08 | ≤0.050 | ≤0.050 | ≤0.030 | — | ≤0.025 | ≤0.010 | Cu+Ni+Cr+Mo ≤0.70 |
a) Upon agreement between the supplier and the buyer and specified in the contract, the lower limit of C content may not be required. If not specified, no requirement applies.
b) For Q245R plates with thickness greater than 60mm, the upper limit of manganese content may be increased to 1.20%.
c) Trace amounts of niobium, vanadium and titanium may be added to Q245R, and the total sum of these three elements shall not exceed 0.050%.
7.1.2 For Q345R and Q370R plates with thickness greater than 60mm, the upper limit of carbon content may be increased to 0.22% and 0.20% respectively; for Q245R plates with thickness greater than 60mm, the upper limit of manganese content may be increased to 1.20%.
7.1.3 Trace amounts of niobium, vanadium and titanium may be added to Q245R, Q345R and Q370R steel, and their contents shall be indicated in the quality certificate. The total sum of these three elements shall not exceed 0.050%, 0.120% and 0.150% respectively.
7.1.4 Upon buyer's request, the nitrogen content of Q420R and Q460R steel plates shall not exceed 0.020% and 0.025% respectively.
7.1.5 Upon buyer's request, an appropriate amount of rare earth elements may be added to 07Cr2AlMoR steel.
7.1.6 The residual elements chromium, nickel and copper shall not exceed 0.30% each, and molybdenum shall not exceed 0.080%. The total content of these elements shall not exceed 0.70%. The supplier may not perform analysis if the guaranteed values are assured.
7.1.7 Upon buyer's request, the carbon equivalent may be specified for Q245R, Q345R, Q370R, Q420R, Q460R, the value agreed upon by the supplier and buyer.
7.1.8 The allowable deviation of finished chemical composition shall comply with GB/T 713.1.
7.1.9 The approximate designation comparison between this document and foreign standards is shown in Appendix A.
7.2 Manufacturing Method
The manufacturing method of steel shall comply with GB/T 713.1.
7.3 Delivery Condition
7.3.1 The delivery condition of plates and strips is specified in Table 2. Q245R: hot rolled, normalized rolled or normalizing.
7.3.2 18MnMoNbR and 13MnNiMoR steel plates shall have a tempering temperature not lower than 620℃, 15CrMoR and 14Cr1MoR not lower than 650℃, 12Cr2Mo1R, 12Cr1MoVR, 12Cr2Mo1VR and 07Cr2AlMoR not lower than 680℃.
7.3.3 With the buyer's consent, normalized plus tempered plates with thickness greater than 50mm may be delivered by normalizing (accelerated cooling allowed) plus tempering.
7.4 Mechanical and Technological Properties
7.4.1 The mechanical and technological properties of plates shall comply with GB/T 713.1.
7.4.2 The results of tensile test, Charpy (V-notch) impact test and bending test shall comply with Table 2.
| Grade | Delivery Condition | Thickness/mm | Tensile Test | Impact Test | 180° Bending Test | |||
|---|---|---|---|---|---|---|---|---|
| Tensile Strength Rm/MPa | Lower Yield Strength ReL/MPa (≥) | Elongation A/% (≥) | Temp/℃ | Impact Energy KV2/J (≥) | ||||
| Q245R | Hot rolled, normalized rolled or normalizing | 3~16 | 400~520 | 245 | 25 | 0 | 34 | D=1.5a |
| >16~36 | 400~520 | 235 | 25 | D=1.5a | ||||
| >36~60 | 400~520 | 225 | 25 | D=1.5a | ||||
| >60~100 | 390~510 | 205 | 24 | D=2a | ||||
| >100~150 | 380~500 | 185 | 24 | D=2a | ||||
| >150~250 | 380~500 | 185 | 24 | D=2a | ||||
7.4.3 For plates with thickness greater than 60mm, upon agreement between the supplier and the buyer and specified in the contract, the bending test may be omitted.
7.4.4 For chromium-molybdenum alloy steel plates for hydrogen service, the mechanical properties shall comply with Appendix B.
7.4.5 Upon buyer's request, Q245R, Q345R and 13MnNiMoR may be subjected to -20℃ impact test instead of the 0℃ impact test in Table 2, and the impact energy value shall comply with Table 2 (34J for Q245R).
7.4.6 Upon buyer's request, high temperature tensile test may be carried out on plates with thickness greater than 20mm, and the test temperature shall be specified in the contract. The Rp0.2 or ReL values at high temperature shall comply with Table 3.
| Grade | Thickness/mm | Test Temperature/℃ | ||||||||
|---|---|---|---|---|---|---|---|---|---|---|
| 100 | 150 | 200 | 250 | 300 | 350 | 400 | 450 | 500 | ||
| Rp0.2 (or ReL) / MPa, not less than | ||||||||||
| Q245R | >20~36 | 210 | 200 | 186 | 167 | 153 | 139 | 129 | 121 | — |
| >36~60 | 200 | 191 | 178 | 161 | 147 | 133 | 123 | 116 | — | |
| >60~100 | 184 | 176 | 164 | 147 | 135 | 123 | 113 | 106 | — | |
| >100~150 | 168 | 160 | 150 | 135 | 120 | 110 | 105 | 95 | — | |
| >150~250 | 160 | 150 | 145 | 130 | 115 | 105 | 100 | 90 | — | |
7.4.7 Upon buyer's request, through-thickness tensile test may be carried out, with technical requirements specified in the contract.
7.4.8 Upon buyer's request, drop weight test may be carried out, with technical requirements specified in the contract.
7.5 Hydrogen Induced Cracking Test
Upon buyer's request, hydrogen induced cracking (HIC) test may be specified for non-alloy and alloy steel for HIC service, with specific requirements in Appendix C, and the qualified grade shall be specified in the contract.
7.6 Non-destructive testing
Upon buyer's request, each steel plate and strip shall be subjected to ultrasonic testing. The test method shall comply with NB/T 47013.3, and the acceptance level shall be specified in the contract.
7.7 Surface Quality
The surface quality of steel plates and strips shall comply with GB/T 713.1.
7.8 Other Additional Requirements
Upon buyer's request and agreement between the supplier and the buyer and specified in the contract, additional technical requirements for chromium-molybdenum steel plates for hydrogen service may be specified. For chromium-molybdenum alloy steel plates for hydrogen service, the chemical composition shall comply with Table 1 and Appendix B.
8 Test Methods
8.1 The chemical composition test shall generally be carried out according to GB/T 4336, GB/T 20123, GB/T 20124, GB/T 20125 or other common methods. In case of arbitration, it shall be carried out according to the GB/T 223 series standards.
8.2 The test methods for mechanical and technological properties of steel plates shall comply with Table 4.
| No. | Inspection Item | Sample Quantity | Sampling Method | Sampling Direction | Test Method |
|---|---|---|---|---|---|
| 1 | Chemical composition | 1 per heat | GB/T 20066 | — | 8.1 |
| 2 | Tensile test | 1 per batch | GB/T 2975 | Transverse | GB/T 228.1 |
| 3 | Through-thickness tensile test | 3 per batch | GB/T 5313 | — | GB/T 5313 |
| 4 | Bending test | 1 per batch | GB/T 2975 | Transverse | GB/T 232 |
| 5 | Impact test | 3 per batch | GB/T 2975 | Transverse | GB/T 229 |
| 6 | High temperature tensile test | 1 per heat | GB/T 2975 | Transverse | GB/T 228.2 |
| 7 | Drop weight test | — | GB/T 6803 | — | GB/T 6803 |
| 8 | HIC test | — | GB/T 8650 | — | GB/T 8650 |
| 9 | Ultrasonic testing | Each plate | — | — | NB/T 47013.3 |
| 10 | Dimensions & shape | Each plate | — | — | Suitable measuring tools |
| 11 | Surface | Each plate | — | — | Visual inspection |
9 Inspection Rules
9.1 Inspection and Acceptance The inspection of steel plates shall be carried out by the supplier's quality inspection department.
9.2 Batch Formation Rules
9.2.1 Steel plates shall be accepted in batches. Each batch shall consist of plates of the same designation, same heat number, same thickness, same rolling process, and same heat treatment system. The batch weight shall not exceed 30t. Plates with single weight exceeding 30t shall be batched individually.
9.2.2 For plates delivered in normalized (accelerated cooling allowed) plus tempered condition, they shall be batched by each heat treatment piece.
9.2.3 Upon buyer's request and agreement, mechanical property inspection may be carried out per rolling piece for plates with thickness greater than 16mm.
9.3 Sampling Rules
9.3.1 The sampling position for mechanical property test shall comply with GB/T 2975. For plates with thickness greater than 40mm, the axis of the impact sample shall be located at 1/4 of the thickness. Upon buyer's request and agreement, the axis may be located at 1/2 of the thickness.
9.3.2 The sample quantity, sampling direction and sampling method for each batch of plates shall comply with Table 4.
9.4 Re-inspection and Judgment The re-inspection and judgment rules shall comply with GB/T 713.1.
9.5 Rounding of Numerical Values The rounding rules shall comply with GB/T 713.1.
10 Packaging, Marking and Quality Certificate
The packaging, marking and quality certificate of steel plates shall comply with GB/T 713.1.
Appendix A (Informative) Approximate Designation Comparison
| GB/T 713.2—2023 | ISO 9328:2018 | EN 10028:2017 | ASME II -A-2021 |
|---|---|---|---|
| Q245R | P265GH | P265GH | SA516 Gr.60 |