GB/T 713 18MnMoNbR Steel Plate | 18MnMoNbR Vessel Plate
What is GB/T 713 18MnMoNbR Steel?
GB/T 713 18MnMoNbR, also written GB/T 713.2 18MnMoNbR and 18MnMoNbR steel plate, is a Chinese Mn-Mo-Nb boiler and pressure-vessel plate. Current product rules sit in GB/T 713.2-2023. Buyers still search GB/T 713. The name itself is the search term: about 0.18% C, Mn, Mo, Nb, and R for vessel. Yield is 400 MPa at 30–60 mm. Tensile is 570–720 MPa. Delivery is normalizing plus tempering. Tempering shall not be lower than 620 °C. Impact is commonly 0 °C, 47 J. SHH STEEL is a global steel mill sourcing partner and steel manufacturer & exporter (mill-direct, China origin) for this grade.
A purchase order that only says “MnMoNb vessel plate” is incomplete. Write GB/T 713 18MnMoNbR. Do not ship Q345R or Q370R against an 18MnMoNbR drawing. Do not ship 13MnNiMoR against an 18MnMoNbR drawing. Do not ship SA302 Gr.B and stamp 18MnMoNbR because both contain molybdenum.
This page is not Q245R / Q345R carbon vessel plate. It is not Cr-Mo 15CrMoR. It is not QT alloy under ASME SA387. It is not low-temperature 16MnDR under GB/T 713.3.
Company scope: global steel mill sourcing partner – SHH STEEL.
Material Specification
Material Specification
| Specification Element | Requirement | SHH STEEL Compliance |
|---|---|---|
| Grade | GB/T 713 18MnMoNbR | Confirmed |
| Product Specification | GB/T 713.2-2023 (buyers still search GB/T 713) | Applied |
| Service idea | Mn-Mo-Nb boiler and pressure vessels | Confirmed |
| Steel type | Killed Mn-Mo-Nb vessel plate | Confirmed |
| Usual delivery | N+T, temper ≥620 °C | Confirmed |
| Yield idea | 400 MPa at 30–60 mm | Confirmed |
| Tensile | 570–720 MPa at 30–60 mm | Confirmed |
| Supply role | Global steel mill sourcing partner | SHH STEEL |
| Markets | Americas, Europe, Middle East, Africa, Asia | FOB / CIF as ordered |
| Certification | EN 10204 3.1 or 3.2 / third-party | As ordered |
This plate sits in pressure vessel steel plates. ASME comparisons belong on ASME SA302 and ASME SA533, not as automatic substitutes.
Chemical Composition
GB/T 713 18MnMoNbR heat analysis follows GB/T 713.2 Table 1. Product analysis follows the permitted deviations in GB/T 713.1. Write “heat + product analysis” on the order if both are required.
Heat Analysis and Product Analysis — GB/T 713 18MnMoNbR
| Element | Heat Analysis (%) | Product Analysis, when ordered (%) |
|---|---|---|
| Carbon (C), max | 0.21 | 0.23 |
| Silicon (Si) | 0.15 – 0.50 | 0.13 – 0.55 |
| Manganese (Mn) | 1.20 – 1.60 | 1.15 – 1.70 |
| Phosphorus (P), max | 0.020 | 0.025 |
| Sulfur (S), max | 0.010 | 0.015 |
| Molybdenum (Mo) | 0.45 – 0.65 | 0.43 – 0.68 |
| Niobium (Nb) | 0.025 – 0.050 | 0.020 – 0.055 |
| Copper (Cu), max | 0.30 | 0.34 |
| Nickel (Ni), max | 0.30 | 0.34 |
| Chromium (Cr), max | 0.30 | 0.34 |
Molybdenum and niobium are required. That is the difference versus Q345R / Q370R. Do not treat 13MnNiMoR chemistry as 18MnMoNbR. 13MnNiMoR uses nickel. SHH STEEL reports heat analysis on every certificate and product analysis when the order names it.
Mechanical Properties
Yield starts at 400 MPa at 30–60 mm and falls as thickness rises.
Tensile and Yield — GB/T 713 18MnMoNbR
| Thickness (mm) | Yield min (MPa) | Tensile (MPa) |
|---|---|---|
| 30 – 60 | 400 | 570 – 720 |
| 60 – 100 | 390 | 570 – 720 |
| Density | 7.85 g/cm³ | 7.85 g/cm³ |
Elongation is commonly 18% min at 30–60 mm. Impact is 0 °C, 47 J. Elevated-temperature proof stress is published for 200–500 °C. Write the design temperature on the order if the vessel file needs those values.
Elevated-temperature yield (typical published minima, MPa)
| Thickness | 200 °C | 250 °C | 300 °C | 350 °C | 400 °C | 450 °C |
|---|---|---|---|---|---|---|
| 30 – 60 mm | 360 | 355 | 350 | 340 | 310 | 275 |
| 60 – 100 mm | 355 | 350 | 345 | 335 | 305 | 270 |
Do not treat 570–720 MPa tensile as permission to stamp SA302 Gr.B, SA302 Gr.C or SA533 Type B Cl.1 without checking yield, impact and PWHT.
Material Comparison
| Grade | Route | Strength idea | Swap? |
|---|---|---|---|
| GB/T 713 Q345R | C-Mn vessel | 345 / 510–640 | No |
| GB/T 713 Q370R | Fine-grain vessel | 370 / 530–630 | No |
| GB/T 713 18MnMoNbR | Mn-Mo-Nb vessel | 400 / 570–720 | This page |
| GB/T 713 13MnNiMoR | Mn-Ni-Mo vessel | Nickel required | No |
| SA302 Gr.B | Mn-Mo vessel | Related idea | Comparison only |
| 15CrMoR | Cr-Mo vessel | Different alloy | No |
Equivalent Material Grades
These names are project-comparison grades. They are not automatic substitutes.
| Designation | Standard / region | Notes |
|---|---|---|
| GB/T 713 18MnMoNbR | GB/T 713.2-2023 | Name on this page |
| GB/T 713-2014 18MnMoNbR | Previous Chinese edition | Same commercial name |
| GB 6654 18MnMoNbR | Older vessel book | Historical name |
| SA302 Gr.B | SA-302 | Mn-Mo vessel comparison |
| SA302 Gr.C | SA-302 | Mn-Mo-Ni vessel |
| SA302 Gr.D | SA-302 | Higher Ni Mn-Mo-Ni |
| SA533 Type A Cl.1 | SA-533 | Mn-Mo-Ni QT vessel |
| SA533 Type B Cl.1 | SA-533 | Higher Ni QT vessel |
| ASTM A302 | A302 family | ASTM twin of SA302 |
| 13MnNiMoR | GB/T 713.2 | Nickel sister |
| Q345R / Q370R / Q420R | GB/T 713.2 | Carbon / fine-grain sisters |
| 15CrMoR / 14Cr1MoR | GB/T 713.2 | Cr-Mo, not Mn-Mo-Nb |
| SA387 Gr.12 Cl.2 | SA-387 | Cr-Mo, different alloy |
| SA516 Gr.70 | SA-516 | Carbon vessel, no Mo-Nb |
| JIS G3119 SBV1A / SBV1B | JIS G3119 | Mn-Mo-Ni vessel comparison |
| ASTM A36 steel plate | A36 | Structural, not vessel |
ASME SA515, ASME SA387 Grade 22 and ASME SA203 are not 18MnMoNbR.
Mn-Mo-Nb Pressure-Vessel Service
GB/T 713 18MnMoNbR is selected for boilers, drums, thick shells and other pressure equipment that name the Chinese Mn-Mo-Nb vessel book. Molybdenum supports elevated-temperature strength. Niobium supports grain and strength after N+T. It is not automatically an ASME Section VIII plate. If the vessel is ASME, the drawing should name an ASME or ASTM grade such as SA302 Gr.B, SA302 Gr.C or SA533 Type B Cl.1.
SHH STEEL supplies this plate to fabricators in the United States, Mexico, South America, Europe, the Middle East, Africa and Asia. It is not nickel low-temp plate like SA203 Gr.D. It is not QT Ni-Cr-Mo like SA543 Type B Cl.1. It is not Cr-Mo like SA387 Gr.22 Cl.2. Stainless inquiries belong on ASME SA240 or ASTM A240.
Weldability
18MnMoNbR is killed Mn-Mo-Nb vessel plate. Welding is production welding, and Code welding when the equipment is a vessel.
Qualify procedures to the applicable code. For ASME work that happens to use a dual-named plate, use ASME Section IX. Consumables should match the 570–720 MPa tensile band and the molybdenum content, not a plain Q345R procedure and not a SA387 Gr.22 Cl.2 Cr-Mo procedure. Preheat follows thickness and hydrogen control. The fabricator owns the WPS. SHH STEEL can share mill heat data for that review.
Heat Treatment and Delivery Condition
Usual delivery from SHH STEEL is normalized-and-tempered GB/T 713 18MnMoNbR. Tempering shall not be lower than 620 °C. As-rolled shipment is not the default.
If the vessel will see PWHT, test coupons shall follow a simulated cycle when the order names it. This is not the carbon normalize route used on Q345R and not the Cr-Mo N+T route used on 15CrMoR. Special heat treatment, extra simulation or third-party hold points add time. Plan about two months when those extras are on the order.
The certificate lists GB/T 713 18MnMoNbR; heat number; heat analysis; product analysis when ordered; tensile results to the correct thickness column; N+T and tempering temperature; impact at 0 °C or the named temperature; elevated-temperature proof stress when ordered. Certificates may be EN 10204 3.1 or EN 10204 3.2.
Dimensions
Usual supply range from SHH STEEL for 18MnMoNbR vessel plate:
- Thickness: commonly 30 mm – 100 mm. Confirm any request outside that band against mill capability
- Width: 1500 mm – 4000 mm
- Length: 3000 mm – 12000 mm
- Cut-to-length plates and nest sizes inside those limits
Ship plate inquiries belong on shipbuilding steel plates or BV Rules. Weathering plate belongs on EN 10025-5 or Corten A/B. TMCP fine-grain structural belongs on EN 10025-4. QT structural belongs on EN 10025-6. Ordinary structural belongs on EN 10025-2 or JIS G3106.
Tolerances
Dimensional limits follow GB/T 713.1 and the mill rolling standard named on the order. Do not apply ASTM A36/A36M structural tolerances to a Chinese vessel plate without writing them. UT to GB/T 2970, JB/T 4730, EN 10160 or ASTM A435 / A577 / A578 is added when the order names it.
Supplementary Requirements
Most export GB/T 713 18MnMoNbR orders add extras. SHH STEEL does not assume them.
Charpy details. Temperature, energy, location and orientation. GB default is commonly 0 °C / 47 J.
Product analysis. Add this when the destination file wants finished-plate chemistry.
Elevated-temperature proof stress. 200–500 °C or the design temperature.
Simulated PWHT. When the equipment will be stress-relieved.
NDE. UT per the named method.
Z-direction. Z15 / Z25 / Z35 when the drawing names it.
HIC / NACE / SSC. Only when written.
Third-party. EN 10204 3.2, with inspectors arranged for US, Mexican, European, Middle East, Japanese or Korean documentation packages.
Applications
| Industry | Typical components |
|---|---|
| Mn-Mo-Nb vessels | GB/T 713 18MnMoNbR shells |
| Boilers and thick drums | 18MnMoNbR courses |
| Elevated-temperature equipment | 18MnMoNbR plate from SHH STEEL |
| Fabrication | 18MnMoNbR cut to nest sizes |
Stainless inquiries belong on stainless steel products, JIS G4305 or AISI stainless. Other vessel comparisons: SA203 Gr.B, SA302 Gr.A, A516 Grade 70, SA533 Type C Cl.1, SA517 Gr.P, SA738 Gr.C.
Global Delivery & Markets
SHH STEEL is a global steel mill sourcing partner with mill partnerships in China. We supply ASTM, ASME, EN, DIN, JIS and GB steel to buyers outside a single region. Origin is mill-direct, China origin.
SHH STEEL has supplied steel plates to:
- North America: USA, Mexico
- South America: Argentina, Peru and other South American ports
- Central America: El Salvador
- Europe: Spain, Netherlands, Germany and surrounding ports
- Middle East: UAE, Saudi Arabia and nearby Gulf ports
- Africa: South Africa
- South / Southeast Asia: India, Thailand, Singapore, Vietnam, Philippines
- East Asia: Japan, Korea
Typical trade terms: FOB Shanghai, CIF Houston, CIF Rotterdam, CIF Jebel Ali, plus Manzanillo, Callao, Buenos Aires, Barcelona, Durban, Laem Chabang, Ho Chi Minh, Manila, Mumbai, Yokohama and Busan.
Typical lead time for GB/T 713 18MnMoNbR:
- Ex-stock: about 5–7 days
- Mill rolling, standard N+T: about 45 days
- Simulated PWHT, 3.2 or extra NDE: about 2 months
Documents travel with the cargo: mill certificate, packing list, commercial invoice, bill of lading, and EN 10204 3.1 or 3.2 as ordered. Third-party inspection can be arranged before loading. Packing is seaworthy, with edge protection and marking in English as specified on the order.
Why Choose SHH STEEL
SHH STEEL is a global steel mill sourcing partner and steel manufacturer & exporter (mill-direct, China origin). We supply ASTM / ASME / EN / DIN / JIS / GB steel to the USA, Mexico, South America, Europe, the Middle East, Africa and Asia. On GB/T 713 18MnMoNbR that means mill pricing, 18MnMoNbR chemistry reported as heat analysis and as product analysis when ordered, recorded N+T with temper ≥620 °C, tensile results to the correct thickness column, 400 MPa yield at 30–60 mm, 3.1 as standard and 3.2 when specified.
We keep the grade on the order. 18MnMoNbR is not Q345R. 18MnMoNbR is not 13MnNiMoR. 18MnMoNbR is not 15CrMoR. 18MnMoNbR is not SA302 Gr.B unless both books are met. 18MnMoNbR is not SA387 Gr.22 Cl.2.
Company scope: global steel mill sourcing partner – SHH STEEL.
FAQ
- What is 18MnMoNbR steel plate?
- 18MnMoNbR is a GB/T 713 / GB/T 713.2 Mn-Mo-Nb boiler and pressure-vessel plate. Yield is 400 MPa at 30–60 mm and tensile is 570–720 MPa. Delivery is N+T with temper not lower than 620 °C. SHH STEEL supplies this plate as a global steel mill sourcing partner.
- What is the equivalent of 18MnMoNbR?
- The usual ASME comparison is SA302 Grade B. Other comparisons are SA302 Grade C and SA533 Type A / B. Dual marking is possible only when both books are fully met.
- Does GB/T 713 give product analysis for 18MnMoNbR?
- Heat analysis is in GB/T 713.2. Product analysis deviations follow GB/T 713.1. SHH STEEL reports both when written on the purchase order.
- How is 18MnMoNbR different from 13MnNiMoR?
- 18MnMoNbR is Mn-Mo-Nb. 13MnNiMoR is Mn-Ni-Mo. Nickel is required on 13MnNiMoR.
- How is 18MnMoNbR different from Q345R?
- Q345R is C-Mn vessel plate without required Mo and Nb. 18MnMoNbR requires molybdenum and niobium and ships N+T.
- Can SHH STEEL ship 18MnMoNbR to Mexico, South America or Southeast Asia?
- Yes. SHH STEEL has supplied plates to Mexico, Argentina, El Salvador, Peru, Spain, South Africa, India, Thailand, Singapore, Vietnam, the Philippines, Japan and Korea, as well as the USA, Europe and the Middle East.
- What is the delivery time for 18MnMoNbR?
- Ex-stock about 5–7 days. Standard N+T mill rolling about 45 days. Simulated PWHT or 3.2 inspection about 2 months.
- Can SHH STEEL issue EN 10204 3.2 for 18MnMoNbR?
- Yes. EN 10204 3.1 is standard. EN 10204 3.2 is arranged when written on the order.
- What is the density of 18MnMoNbR?
- 7.85 g/cm³.
Conclusion
GB/T 713 18MnMoNbR Steel Plate is Chinese Mn-Mo-Nb boiler and pressure-vessel plate at the 400 MPa yield step, 570–720 MPa tensile at 30–60 mm, N+T delivery with temper not lower than 620 °C. Whether the inquiry says GB/T 713 18MnMoNbR, GB/T 713.2 18MnMoNbR or 18MnMoNbR Vessel Plate, SHH STEEL as a global steel mill sourcing partner and steel manufacturer & exporter (mill-direct, China origin) supplies plate with 18MnMoNbR chemistry, heat and product analysis when ordered, recorded N+T, and EN 10204 3.1 or 3.2 certification.
SHH STEEL supplies GB/T 713 18MnMoNbR Vessel Plate to the USA, Mexico, South America, Europe, the Middle East, Africa and Asia for work that actually names this grade. FOB Shanghai / CIF Houston / Rotterdam / Jebel Ali.
Contact SHH STEEL for mill rolling, stock inquiry, N+T, elevated-temperature testing, 3.2 inspection or a quotation.
GB/T 713 18MnMoNbR Steel Plate, GB/T 713.2 18MnMoNbR, 18MnMoNbR vessel plate, 18MnMoNbR supplier, global steel mill sourcing partner SHH STEEL
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