ASTM A225 Grade C Steel Plate | A225 Gr.C Mn-V-Ni Vessel Plate
What is ASTM A225 Grade C Steel?
ASTM A225 Grade C is the high-strength grade in the current ASTM A225/A225M. The specification covers manganese-vanadium-nickel alloy steel plates intended primarily for welded layered pressure vessels. The live standard lists two grades only: Grade C and Grade D. Older talk about Grade A or Grade B belongs to withdrawn editions. As Direct Mill Supply by SHH STEEL, the plate is produced to ASTM A225/A225M.
The same plate is written A225 Gr.C, A225GRC, A225 GR C, A225 Grade C, ASTM A225 Gr.C, ASME SA225 Grade C, SA225 Gr.C, SA225GRC and A/SA225 Grade C. They all mean Grade C. ASME SA-225/SA-225M is the Code companion used when the vessel will be stamped to ASME Section VIII.
Grade C is not the mid-strength line. Grade C takes 725–930 MPa tensile and 485 MPa yield at all thicknesses. Grade D takes 550–725 MPa through 75 mm and 515–690 MPa over 75 mm. If the drawing says Grade D, do not ship Grade C as a silent upgrade. If the drawing says Grade C, do not ship Grade D and call it close. Carbon caps are also different: Grade C 0.25% max, Grade D 0.20% max.
This is not carbon vessel plate. If the drawing says SA516 Gr.70 or A516 Gr.70, open that page. SA516 / A516 is fine-grain carbon. If the drawing says SA285 Gr.C or A285 Gr.C, that is low-to-intermediate tensile carbon. ASTM A225 Grade C is a Mn-V-Ni alloy.
It is not nickel cryogenic plate like SA203 Gr.D or A203 Gr.D. Those plates live on 3.5% nickel. A225 Grade C lives on manganese, vanadium and 0.40–0.70% nickel. It is not Mn-Mo plate like SA302 Gr.B. It is not Cr-Mo like SA387 Gr.22 Cl.2. It is not QT 690 like SA517 Gr.Q. SA517 is quench and temper. A225 Grade C over 50 mm is normalized; 50 mm and under is usually as-rolled unless ordered otherwise.
The steel shall be killed and shall conform to the fine austenitic grain size requirement of ASTM A20 / ASME SA-20. Maximum thickness is limited only by the ability of the chemistry to meet the tensile table. Mills commonly offer about 8–150 mm.
For Code work the plate is dual-marked ASTM A225 Grade C / ASME SA225 Grade C. Certificates can be EN 10204 3.1 or EN 10204 3.2.
When a project is still choosing alloy vessel plate, a China mill Agent path through SHH STEEL puts A225GRC next to SA302 Gr.C, SA387 Gr.11 Cl.2 and SA537 Cl.1. Mn-Mo, Cr-Mo, carbon heat-treated and Mn-V-Ni are four different purchases.
Material Specification
| Specification Element | Requirement | SHH STEEL Compliance |
|---|---|---|
| Grade | ASTM A225 Grade C / A225 Gr.C / A225GRC | Confirmed |
| Product Specification | ASTM A225/A225M | Applied |
| Companion Spec | ASME SA225 Grade C / SA225GRC | Dual cert available |
| General Requirements | ASTM A20 / ASME SA-20 | Applied |
| Intended use | Welded layered pressure vessels | As specified |
| Steel practice | Killed, fine austenitic grain | Confirmed |
| Heat treatment | Normalized over 50 mm; AR usual ≤50 mm | Confirmed |
| Typical Supply | 8 mm – 150 mm | By mill enquiry |
| Width / Length | Up to about 4000 mm / 12000 mm | Mill capability |
| Certification | EN 10204 3.1 or 3.2 / third-party | As ordered |
This plate is a vessel product. It is not structural ASTM A36 steel plate. It is not silicon-killed high-temp carbon like SA515 Gr.70.
Chemical Composition
Chemistry for ASTM A225 Grade C is reported as heat analysis and product analysis under ASTM A225/A225M Table 1. Vanadium and nickel together with a high manganese maximum are the grade markers.
Heat Analysis — ASTM A225 Grade C / A225 Gr.C
| Element | Heat Analysis (%) |
|---|---|
| Carbon (C), max | 0.25 |
| Manganese (Mn), max | 1.60 |
| Phosphorus (P), max | 0.025 |
| Sulfur (S), max | 0.025 |
| Silicon (Si) | 0.15 – 0.40 |
| Vanadium (V) | 0.13 – 0.18 |
| Nickel (Ni) | 0.40 – 0.70 |
Product Analysis — A225GRC / SA225 Grade C
| Element | Product Analysis (%) |
|---|---|
| Carbon (C), max | 0.25 |
| Manganese (Mn), max | 1.72 |
| Phosphorus (P), max | 0.025 |
| Sulfur (S), max | 0.025 |
| Silicon (Si) | 0.13 – 0.45 |
| Vanadium (V) | 0.11 – 0.20 |
| Nickel (Ni) | 0.37 – 0.73 |
Carbon 0.25% max applies to both heat and product analysis. Grade D is tighter on carbon at 0.20% max. Manganese is a maximum, not a min–max band: 1.60% heat, 1.72% product. Vanadium on Grade C is 0.13–0.18% heat. Nickel is 0.40–0.70% heat on both C and D.
Compare that ladle with nearby alloys before anyone tries a silent swap. SA203 Gr.A and A203 Gr.A live on nickel, not vanadium. SA302 Gr.A lives on molybdenum. SA387 Gr.12 Cl.2 lives on chromium-molybdenum. Grade C in A225 is none of those ladles.
If the drawing says ASTM A225 Grade C or A225GRC, the ladle must sit in the Grade C table. SHH STEEL reports heat analysis on every certificate and adds product analysis when A20 / SA-20 or the vessel specification requires it.
Tighter phosphorus, sulfur or residuals are supplementary. Vacuum treatment is available when written on the order.
Mechanical Properties
Grade C uses one tensile line at all thicknesses. That is the opposite of Grade D, which splits at 75 mm.
Tensile Requirements — ASTM A225 Grade C per ASTM A225/A225M
| Property | All thicknesses |
|---|---|
| Tensile strength | 725 – 930 MPa (105 – 135 ksi) |
| Yield strength, min | 485 MPa (70 ksi) |
| Elongation in 50 mm (2 in.), min | 20% |
Yield is determined by the 0.2% offset method or the 0.5% extension-under-load method. That 485 MPa yield line is why Grade C exists. Grade D is 415 MPa through 75 mm and 380 MPa over 75 mm. Do not read “A225” and assume Grade D numbers.
Density is 7.85 g/cm³. Hardness is not a default line. Charpy is not a hidden default at −20 °C or −46 °C. If the vessel needs a stated test temperature and energy, write it as a supplementary requirement under A20 / SA-20.
Compare strength class carefully. SA537 Cl.2 is carbon QT at a different route. SA517 Gr.F is QT 690 MPa class with a 65 mm ceiling. SA516 Gr.70 is fine-grain carbon at 485–620 MPa. A225 Grade C is not a substitute for those pages.
Material Comparison
| Grade | Alloy / route | Strength idea | Swap? |
|---|---|---|---|
| ASTM A225 Gr.C / ASME SA225 Gr.C | Mn-V-Ni; N over 50 mm | 725–930 MPa / 485 MPa yield | This page |
| ASTM A225 Gr.D / ASME SA225 Gr.D | Mn-V-Ni; N all thicknesses | 550–725 / 515–690 MPa | Same family, lower strength |
| SA203 Gr.F | Ni QT / low-temp | Nickel cryogenic family | No |
| SA302 Gr.B | Mn-Mo | Intermediate vessel | No |
| SA387 Gr.22 Cl.2 | Cr-Mo | Elevated-temp | No |
| SA516 Gr.70 | Fine-grain carbon | 485–620 MPa | No |
| SA517 Gr.B | QT alloy | 690 MPa class, 32 mm max | No |
| SA285 Gr.C | Carbon PV | 380–515 MPa | No |
Order ASTM A225 Grade C when the drawing names Grade C. SHH STEEL does not swap A225GRC for A516 Gr.70 or SA517 Gr.P without a written revision.
Welded Layered Vessel Service
ASTM A225 Grade C exists because layered vessels need a weldable Mn-V-Ni plate with a 70 ksi yield. Vanadium refines grain and lifts yield. Nickel at 0.40–0.70% helps toughness. Manganese carries hardenability.
Allowable stress for Code work comes from ASME Section II Part D for SA-225 Grade C after dual marking. Impact temperature is an order number.
Typical use is layered shells, high-pressure process drums specified to A225 / SA225, and other fusion-welded equipment written as Mn-V-Ni vessel plate. It is not a replacement for SA387 Gr.91 Cl.2 creep service and not a replacement for SA203 Gr.A nickel low-temp service.
Weldability
A225GRC is a vanadium-bearing alloy vessel plate. Welding is not the same job as welding SA516 Gr.60 or SA285 Gr.B.
Procedures for Code work are qualified to ASME Section IX. Low-hydrogen practice is mandatory thinking. Vanadium and the 0.25% carbon cap raise hardenability enough that a cold, restrained start can crack.
Preheat depends on thickness, restraint, hydrogen and the qualified WPS. Simulated PWHT of mill coupons should be on the purchase order whenever the vessel specification includes PWHT.
Do not copy a SA387 Gr.22 Cl.1 Cr-Mo procedure or a SA517 Gr.A QT procedure onto ASTM A225 Grade C. The fabricator owns the WPS.
Heat Treatment
Heat treatment of ASTM A225 Grade C is thickness-dependent in the specification:
- Grade C plates over 50 mm (2 in.) shall be normalized.
- Grade C plates 50 mm and under are usually supplied as-rolled. They may be ordered normalized, stress-relieved, or both.
Grade D plates of all thicknesses shall be normalized. Do not apply the Grade D rule to every Grade C plate, and do not skip normalize on Grade C over 50 mm.
Quench-and-temper practice used for SA517 Gr.E is not this grade. SHH STEEL reports the actual heat-treatment condition on the MTC.
Delivery Condition
Usual delivery is as-rolled to 50 mm and normalized above 50 mm, unless the order says otherwise.
The certificate lists ASTM A225 Grade C and, when dual certified, ASME SA225 Grade C; heat number; heat analysis; product analysis when ordered; tensile results; heat-treatment temperatures; Charpy results when ordered; and supplementary tests.
Certificates may be EN 10204 3.1 or EN 10204 3.2.
Dimensions
Usual supply range from SHH STEEL for A225 Gr.C Mn-V-Ni vessel plate:
- Thickness: 8 mm – 150 mm
- Width: up to about 4000 mm
- Length: up to about 12000 mm
State thickness clearly. At 50 mm the usual heat-treatment practice changes.
Tolerances
Dimensional limits follow ASTM A20 / ASME SA-20. UT to A435, A577 or A578 is commonly added on Grade C because strength and restraint are high.
Supplementary Requirements
Most export ASTM A225 Grade C orders add extras. SHH STEEL does not assume them.
Simulated PWHT. Same-heat coupons follow the vessel cycle. On 485 MPa yield alloy this is the test that prevents a shop surprise.
Charpy details. Temperature, energy, specimen orientation and location as agreed.
NDE. UT to A435 / A577 / A578; edge MT/PT after cutting.
Hardness survey. After normalize or after simulated PWHT.
Restricted chemistry. Tighter P, S, residuals or vacuum treatment.
HIC / NACE. Only when cited. Grade C is not automatically sour-service plate.
Z-direction. A770 or Z15/Z25/Z35 when written.
Third-party. EN 10204 3.2.
Equivalent Material Grades
| Designation | Standard | Notes |
|---|---|---|
| ASTM A225 Grade C / A225 Gr.C / A225GRC | ASTM A225/A225M | Product name on this page |
| ASME SA225 Grade C / SA225 Gr.C / SA225GRC | ASME SA-225/SA-225M | Code companion |
| ASTM A225 Grade D | A225/A225M | Mid-strength grade in the same spec |
| EN 10028-6 P690 related | EN | Project comparison only |
| JIS G3115 SPV490 related | JIS G3115 | Japanese PV comparison |
| GB/T 19189 related | GB | Confirm chemistry |
| A537CL1 | ASTM A537 | Heat-treated carbon; not a substitute |
| A302 Gr.B | ASTM A302 | Mn-Mo; not a substitute |
For stamping, write ASTM A225 Grade C or dual A225 / SA225 Grade C.
Applications
| Industry | Typical components |
|---|---|
| Layered pressure vessels | ASTM A225 Grade C layers and A225GRC courses |
| Petrochemical | A225 Grade C process drums |
| Energy and process | ASTM A225 Grade C Mn-V-Ni vessel plate |
| High-pressure equipment | A225 Gr.C shells |
| Dual-certified export | A225 / SA225 Gr.C plate |
| Fabrication | A225GRC cut to nest sizes |
Do not use this grade as a silent stand-in for SA387 Gr.5 Cl.2 or SA517 Gr.S.
Why Choose SHH STEEL
SHH STEEL works as a China Mill Direct Exporter for plates to ASTM A225/A225M. On ASTM A225 Grade C that means mill pricing, dual A225/SA225 marking, heat and product analysis including the 0.13–0.18% vanadium band, recorded heat treatment by thickness, 3.1 as standard and 3.2 when specified.
We keep the order on the right grade. Grade C is not Grade D. A225 is not SA285 Gr.A. A225 is not SA516 Gr.55. A225 Gr.C is not SA517 Gr.Q. If the drawing is nickel low-temp, we point the inquiry to SA203 / A203. If it is Cr-Mo elevated-temp, we point it to SA387. If it is QT 690, we point it to SA517 / A517.
Company scope: China steel Mill Agent-SHH STEEL.
FAQ
-
What names are used for ASTM A225 Grade C?
- Buyers write A225 Gr.C, A225GRC, A225 GR C, A225 Grade C, ASME SA225 Grade C, SA225 Gr.C and SA225GRC. SHH STEEL prints the wording on the purchase order.
-
Does ASTM A225 still have Grade A and Grade B?
- Not in the current specification. ASTM A225/A225M-17(2022) and ASME SA-225 list two grades only: Grade C and Grade D.
-
Is ASTM A225 Grade C the same as ASME SA225 Grade C?
- Chemistry and tensile limits match. ASTM A225 is the product spec. ASME SA-225 is the Code version. As China mill-Direct Supply, SHH STEEL dual-certifies A225 Gr.C / SA225 Gr.C when the vessel must be stamped.
-
What is the yield strength of A225 Gr.C?
- 485 MPa (70 ksi) minimum at all thicknesses. Tensile is 725–930 MPa. Elongation is 20% in 50 mm, per ASTM A225.
-
Why specify Grade C instead of Grade D?
- Grade C is the high-strength grade. Grade D is the mid-strength line with lower carbon and two tensile lines at 75 mm. Follow the grade on the drawing.
-
Is A225GRC the same as A516 Gr.70, A203 or A517?
- No. A516 is fine-grain carbon. A203 is nickel low-temperature plate. A517 is quenched-and-tempered high-strength alloy. ASTM A225 Grade C is Mn-V-Ni vessel plate.
-
What heat treatment does ASTM A225 Grade C require?
- Normalize over 50 mm. Plates 50 mm and under are usually as-rolled unless ordered normalized or stress-relieved. Grade D is normalized at all thicknesses.
-
Can welding of A225 Gr.C be qualified to ASME Section IX?
- Yes. Use a low-hydrogen WPS written for this vanadium-bearing alloy. The fabricator owns the procedure.
-
Can SHH STEEL issue EN 10204 3.2 on ASTM A225 Grade C?
- Yes. EN 10204 3.1 is standard. EN 10204 3.2 is arranged when written on the order.
-
What is the density of A225 Gr.C plate?
- 7.85 g/cm³.
Conclusion
ASTM A225 Grade C Steel Plate is the high-strength manganese-vanadium-nickel vessel grade in the current ASTM A225/A225M, which lists only Grade C and Grade D. Whether the inquiry says A225 Gr.C, A225GRC, A225 Grade C, SA225 Gr.C or ASME SA225 Grade C, SHH STEEL supplies plate with heat and product analysis, thickness-correct heat treatment, the 485 MPa yield line, agreed extras, and EN 10204 3.1 or 3.2 certification.
As a China mill Distributor, SHH STEEL provides ASTM A225 Grade C / A225 Gr.C Mn-V-Ni Vessel Plate for ASME Section VIII layered-vessel fabrication.
Contact SHH STEEL for mill rolling, dual A225/SA225 marking, 3.2 inspection or a quotation.
ASTM A225 Grade C Steel Plate, A225 Gr.C, A225GRC, ASME SA225 Grade C, Mn-V-Ni vessel plate, A225 Grade C supplier, Direct Mill Supply by SHH STEEL
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