ASTM A662 Grade A Steel Plate | A662 Gr.A Low Temp Vessel Plate supplier
What is ASTM A662 Grade A Steel?
STM A662 Grade A, also searched as A662 Gr.A, A662GRA, A662-A, A662 Gr A, ASTM A662 Gr.A and SA662 Grade A, is the lowest-carbon grade in ASTM A662/A662M. That book covers carbon-manganese-silicon pressure-vessel plates for moderate and lower temperature welded service where improved notch toughness matters.
The book has only three grades: A, B and C. This page is Grade A. Grade B raises carbon and manganese and lifts tensile to 450–585 MPa. Grade C lifts tensile again to 485–620 MPa and yield to 295 MPa. Do not stamp Grade A chemistry as Grade B. Do not treat A662 as ASTM A516 Grade 60 unless both books are fully met. Do not treat A662 as ASTM A537CL1. A537 is a different heat-treated vessel book. Do not treat A662 as EN 10028-3 P275N unless both books are met.
ASME Code work uses SA-662/SA-662M. SA-662 Grade A is the same chemistry and the same tensile table. If the drawing says SA662 Gr.A, the mill still rolls ASTM A662 Grade A chemistry and prints the book the purchase order names. There is no extra “Class” under A662.
Grade A is the lean member of the family. Heat analysis carbon is 0.14% max. That is why fabricators pick it when they want the 400–540 MPa tensile line and a cleaner weld heat. All Grade A plate is normalized. Grades B and C under 40 mm may ship as-rolled; Grade A does not get that option.
Steel is killed and must meet the fine austenitic grain size rule in A20/A20M. General requirements follow A20. Density is 7.85 g/cm³. Typical hardness after normalize sits around 130–170 HBW.
SHH STEEL is a global steel mill sourcing partner and steel manufacturer & exporter (mill-direct, China origin). We source A662 Gr.A from first-line Chinese mills, print heat and product analysis, record normalize on the certificate, and ship plate to fabricators in the United States, Europe, the Middle East, Southeast Asia, Africa and South America.
Related category pages: pressure vessel steel plates, ASTM A516, ASME SA662 and carbon steel plates.
Material Specification
| Specification Element | Requirement | SHH STEEL Compliance |
|---|---|---|
| Plate book | ASTM A662/A662M Grade A | Confirmed |
| Code companion | ASME SA-662 Grade A | Confirmed when ordered |
| Other search names | A662 Gr.A, A662GRA, A662-A, A662 Gr A | Covered |
| Steel type | Killed C-Mn-Si vessel plate | Confirmed |
| Grain size | Fine austenitic grain, A20 | Confirmed |
| Heat treatment | Normalized (all thicknesses) | Confirmed |
| General requirements | A20 / SA-20 | Confirmed |
| Tensile | 400–540 MPa (58–78 ksi) | Confirmed |
| Yield | 275 MPa (40 ksi) min | Confirmed |
| Product analysis | Table 1 product column when ordered | Confirmed |
| Supply role | Global steel mill sourcing partner | SHH STEEL |
| Certification | EN 10204 3.1 or 3.2 / third-party | As ordered |
Sister grades in the same book are Grade B and Grade C. Nearby vessel pages that buyers compare, but must not swap blindly, include ASTM A285 Grade C, ASTM A515 Grade 60, ASME SA537 Class 1 and GB/T 713 Q245R.
Chemical Composition
Grade A is the lowest-carbon heat in A662. That is the point of the grade. Ladle analysis is the mill table. Product analysis, when ordered, uses the product column in Table 1.
Heat Analysis and Product Analysis — ASTM A662 Grade A
| Element | Heat analysis (%) | Product analysis (%) |
|---|---|---|
| Carbon (C), max | 0.14 | 0.17 |
| Manganese (Mn) | 0.90 – 1.35 | 0.84 – 1.46 |
| Phosphorus (P), max | 0.025 | 0.025 |
| Sulfur (S), max | 0.025 | 0.025 |
| Silicon (Si) | 0.15 – 0.40 | 0.13 – 0.45 |
Grade B heat carbon is 0.19% max. Grade C heat carbon is 0.20% max and manganese starts at 1.00%. If the purchase order writes product analysis, SHH STEEL prints both columns. Vacuum carbon-deoxidized steel is A20 Supplementary Requirement S17 and only applies when named.
Do not treat this chemistry as ASTM A36. A36 is structural plate, not A662 vessel plate. Do not treat it as A572 Gr.50. A572 is HSLA structural plate.
Mechanical Properties
Buyers search A662 Gr.A mechanical properties, A662GRA yield, A662 Grade A tensile and SA662 Gr.A elongation.
Tensile Properties — ASTM A662 Grade A
| Property | Requirement |
|---|---|
| Tensile strength | 58–78 ksi / 400–540 MPa |
| Yield strength, min | 40 ksi / 275 MPa |
| Elongation in 8 in. (200 mm), min | 20% |
| Elongation in 2 in. (50 mm), min | 23% |
Yield is determined by the 0.2% offset method or the 0.5% extension-under-load method. Elongation adjustments follow A20 when thickness requires them.
Grade B uses the same 275 MPa yield but a higher tensile band of 450–585 MPa. Grade C uses 295 MPa yield and 485–620 MPa tensile. If the calculation needs 485 MPa minimum tensile, Grade A is the wrong line.
Impact is not automatic. A662 exists because buyers want better low-temperature notch toughness than ordinary carbon plate, but the joules and the test temperature still have to be written on the purchase order. Typical extras are 20 J or 27 J at −20 °C, 0 °C or −46 °C, transverse, per A20 supplementary impact rules.
Density is 7.85 g/cm³. Hardness is not a Table 2 requirement; mills usually report about 130–170 HBW after normalize.
Material Comparison
| Grade | Book | Tensile | Yield | Swap? |
|---|---|---|---|---|
| A662 Grade A | A662/A662M | 400–540 MPa | 275 MPa | This page |
| A662 Grade B | A662/A662M | 450–585 MPa | 275 MPa | No |
| A662 Grade C | A662/A662M | 485–620 MPa | 295 MPa | No |
| SA662 Grade A | SA-662/SA-662M | Same table | Same | Code name |
| A516 Gr.60 | A516 | 415–550 MPa | 220 MPa (to 50 mm) | Comparison only |
| A537 CL1 | A537 | 485–620 MPa | 345 MPa | No |
| P275N | EN 10028-3 | 390–510 MPa | 275 MPa | Comparison only |
| Q245R | GB/T 713 | 400–520 MPa | 245 MPa | Comparison only |
Equivalent Material Grades
There is no official one-to-one worldwide twin for A662 Gr.A. What buyers compare is a 400–540 MPa C-Mn-Si vessel plate with 275 MPa yield and a normalize route.
In the United States the Code name is SA-662 Grade A. See the ASME SA662 category. ASTM A516 Grade 60 is the plate most people actually stock. It is not A662. ASTM A515 Grade 60 is a high-temperature carbon vessel comparison. ASTM A285 Grade C is a lower-strength vessel comparison.
In Europe compare EN 10028-2 P265GH or EN 10028-3 P275N. P275NH is the elevated-temperature sister in that family. Dual mark only when both books are met. See EN 10028-3 and EN 10028-2.
In Japan compare JIS G3103 SB410 or JIS G3115 SPV235. In China compare GB/T 713 Q245R. Q245R yield is named 245 MPa, not 275 MPa. Q345R is closer to Grade C or A516-70, not Grade A.
| Designation | Country / region | Standard | Notes |
|---|---|---|---|
| A662 Gr.A / A662GRA | USA | ASTM A662/A662M | Name on this page |
| SA662 Grade A | USA | ASME SA-662 | Code companion |
| A662 Grade B | USA | A662/A662M | Higher tensile sister |
| A662 Grade C | USA | A662/A662M | Highest tensile sister |
| A516 Gr.60 | USA | A516 | Common stock comparison |
| P275N | Europe | EN 10028-3 | Fine-grain comparison |
| P265GH | Europe | EN 10028-2 | High-temp carbon comparison |
| SB410 | Japan | JIS G3103 | Boiler comparison |
| SPV235 | Japan | JIS G3115 | Vessel comparison |
| Q245R | China | GB/T 713 | Vessel comparison |
Moderate and Lower Temperature Vessel Service
Buyers pick A662 Gr.A when a Section VIII or similar file wants C-Mn-Si plate with improved notch toughness and does not need the higher tensile band of Grade B or Grade C. Search phrases such as A662GRA, A662 Grade A, A662-A and SA662 Gr.A all point here.
It is the wrong plate for a 70 ksi shell. That work is A516 Grade 70 or A662 Grade C after the purchase order is revised. It is the wrong plate for a 345 MPa heat-treated shell. That work is A537 CL1. It is the wrong plate for −101 °C nickel steel. That work sits on ASME SA203 or EN 10028-4. It is the wrong plate for ordinary building frames. That work sits on ASTM A36 steel plate or structural steel plates.
SHH STEEL supplies this plate to fabricators in the United States, Mexico, Argentina, Spain, the Netherlands, Germany, the UAE, Saudi Arabia, India, Singapore, Vietnam and Korea when the file actually names Grade A.
Weldability
ASTM A662 Grade A is killed C-Mn-Si plate with 0.14% max heat carbon. That low carbon is why shops like it. Treat welding as production welding for pressure equipment. Preheat, heat input and interpass have to stay inside a written WPS.
Typical consumables for this strength line are AWS A5.1 E7018, or matching GMAW / SAW wires qualified on a 60 ksi family. A procedure written for A516 Gr.70 is a higher-tensile family. A procedure written for A572 Gr.50 is structural HSLA, not A662. After heavy cold forming, a stress relief or a new normalize may be required. The fabricator owns the WPS. SHH STEEL can share mill heat data and CEV for that review.
Heat Treatment and Delivery Condition
Usual delivery from SHH STEEL for A662 Gr.A is normalized.
The book is explicit: all plates of Grade A shall be normalized. Grades B and C under 40 mm may ship as-rolled. Grade A does not. If the mill skipped normalize, the plate cannot be certified A662 Grade A.
Normalizing is typically 880–920 °C, soaked through, then air cooled. Fine austenitic grain per A20 is part of the manufacture clause, not an optional extra.
If the fabricator hot-forms outside the mill window, a new normalize is usually required. Simulated PWHT coupons are an extra. Write the soak temperature and time if the vessel cycle must be copied on the test piece.
The certificate lists ASTM A662 Grade A (and SA-662 Grade A when dual-marked); heat number; heat analysis and product analysis when ordered; tensile to Table 2; normalized delivery; impact when ordered. Certificates may be EN 10204 3.1 or EN 10204 3.2.
Dimensions
Usual supply range from SHH STEEL for A662 Gr.A low temp vessel plate:
- Thickness: commonly 6 mm – 50 mm, heavier plate by enquiry when the heat still meets Table 2
- Width: 1500 mm – 4000 mm
- Length: 3000 mm – 12000 mm
Current mill practice often stops around 50 mm because that is where most A662 vessels live. Thicker plate is possible if the composition still hits 400–540 MPa and 275 MPa yield. Cut-to-size shells and heads are available. Browse more vessel sizes on pressure vessel steel plates and the products index.
Tolerances
Dimensional limits for ASTM A662 Grade A follow A20 / SA-20 unless the purchase order names another table. Do not apply structural A6 extras unless the order writes them.
Typical A20 thickness tolerance idea for A662 Gr.A
| Nominal thickness (mm) | Usual minus (mm) | Usual plus (mm) |
|---|---|---|
| 6 – 10 | −0.3 | +0.8 |
| 10 – 20 | −0.4 | +0.9 |
| 20 – 30 | −0.4 | +1.0 |
| 30 – 40 | −0.5 | +1.1 |
| 40 – 50 | −0.5 | +1.2 |
Width on 1500–4000 mm plate is commonly held to about ±20–25 mm unless a tighter extra is named. Length on 3000–12000 mm plate is commonly held to about +50 / 0 mm or ±25 mm by mill practice. Flatness follows A20 unless a tighter class is written. SHH STEEL will not assume a zero-minus extra on A662GRA unless the order says so.
Supplementary Requirements
Grade A already defines chemistry, normalize and the 400–540 MPa table. Extra items still have to be written on the purchase order.
Book name. Write ASTM A662 Grade A. Write SA-662 Grade A if the vessel is Code work.
Impact details. Write temperature, joules, location and orientation. A662 does not pick the temperature for you.
Product analysis. Write it if the file needs the second chemistry column.
Vacuum carbon-deoxidized steel. A20 S17 only when named.
Through-thickness / Z-test. A770 or Z15/Z25/Z35 when needed.
NDE. A435, A577 or A578 as named.
HIC / NACE. Only when the process fluid needs it.
Simulated PWHT. Write soak temperature and time.
Identification and stamping. Heat number, A662 Grade A, thickness and mill logo.
Third-party witness. EN 10204 3.2 with SGS, TÜV, BV, ABS, CCS, DNV or the inspector named.
Applications
| Industry | Typical components |
|---|---|
| Process vessels | A662 Gr.A / A662GRA shells and heads |
| Storage tanks | Moderate and lower temperature courses from SHH STEEL |
| Heat exchangers | Grade A channels and covers |
| LPG and light hydrocarbon | Normalized C-Mn-Si vessel plate |
| Comparison vs Q245R | A662GRA next to Q245R |
| Comparison vs P275N | A662GRA next to P275N |
| Comparison vs A516-60 | A662GRA next to A516 Gr.60 |
A662 Grade A is the plate for a file that wants the lean C-Mn-Si line and a mandatory normalize. It is the wrong plate for a 70 ksi reactor shell. That work is A516-70 or A662 Grade C. It is the wrong plate for a QT high-strength vessel. That work sits on ASTM A517. It is the wrong plate for a 9Ni LNG tank. That work sits on GB/T 713.4 06Ni9DR or EN 10028-4 X8Ni9.
Supply Capability
SHH STEEL sources ASTM A662 Grade A from first-line Chinese mills and ships it on worldwide terms. Partner mills include Wuyang (Wugang), Angang, Shougang, Hanye, Anyang Iron & Steel, Baosteel, Xinyu, Xingcheng, TISCO (Taiyuan), Jiuquan (JISCO) and other qualified mills when the size or normalize route requires it.
Mill test certificates are issued to EN 10204 3.1 as standard. EN 10204 3.2 is arranged when the order names a third-party hold point. Dual marking to SA-662 Grade A is available when the purchase order writes both books.
Usual stock and rolling thickness: 8 mm, 10 mm, 12 mm, 16 mm, 20 mm, 25 mm, 30 mm, 32 mm, 40 mm, 45 mm, 50 mm.
Processing: CNC or flame cutting, bevel, flattening, UT to the named A435 / A578 class.
Trade terms: FOB Shanghai main, CIF destination available. Payment: TT, LC, or TT + LC.
Ocean time from Shanghai: US West 14–18 days; US Gulf 28–35 days; Rotterdam / Antwerp 28–35 days; Jebel Ali 18–25 days; Singapore 7–12 days; other ports quoted.
Third-party: SGS, TÜV, BV, ABS, CCS, GL, VL, DNV, RINA, NK, KR, or the inspector named.
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 in the United States, Europe, the Middle East, Southeast Asia, Africa and South America. Origin is mill-direct, China origin.
SHH STEEL has supplied steel plates to the USA, Mexico, Argentina, Peru, El Salvador, Spain, Netherlands, Germany, UAE, Saudi Arabia, South Africa, India, Thailand, Singapore, Vietnam, the Philippines, Japan and Korea.
Typical lead time: ex-stock 5–7 days; standard rolling and normalize about 45–60 days; 3.2 inspection about 2 months.
Why Choose SHH STEEL
Experience on this grade is simple: print A662 Grade A, keep carbon at 0.14% max on heat analysis, and normalize every plate. SHH STEEL as a global steel mill sourcing partner and steel manufacturer & exporter (mill-direct, China origin) will not ship Grade B chemistry on a Grade A order, will not skip normalize, and will not treat A662 as A516 unless both books are on the certificate.
We keep the book on the order. A662GRA is not A516 Gr.60. A662 Grade A is not A537 CL1. A662 Grade A is not Q245R unless both books are met. If the drawing says 70–90 ksi tensile, we will move the inquiry to Grade C instead of forcing Grade A.
FAQ
- What is ASTM A662 Grade A steel plate?
- ASTM A662 Grade A, also searched as A662 Gr.A, A662GRA and A662-A, is C-Mn-Si pressure-vessel plate for moderate and lower temperature welded service. Tensile is 400–540 MPa and yield is 275 MPa. All Grade A plate is normalized. SHH STEEL supplies this plate worldwide as a global steel mill sourcing partner.
- Is A662 Grade A the same as SA662 Grade A?
- Yes, for chemistry and tensile. SA-662 Grade A is the ASME Code companion. Write the book the vessel stamp needs.
- What is the difference between A662 Grade A and Grade B?
- Both yield at 275 MPa. Grade A tensile is 400–540 MPa with 0.14% max heat carbon. Grade B tensile is 450–585 MPa with higher carbon and manganese. Grade A must be normalized at every thickness. Grade B under 40 mm may ship as-rolled.
- Does A662GRA have product analysis?
- Heat analysis is always on the mill table. Product analysis is added when the purchase order writes it. SHH STEEL prints both columns when ordered.
- What is the Chinese equivalent of A662 Grade A?
- The nearest vessel comparison is GB/T 713 Q245R. It is a strength comparison, not an automatic plate substitute. Q245R yield is named 245 MPa.
- Is A662 Grade A the same as A516 Grade 60?
- No. A516 Gr.60 is a different book and a different chemistry window. Dual mark only when both books are fully met.
- Must A662 Grade A be normalized?
- Yes. The specification requires all Grade A plates to be normalized.
- What is the delivery time for A662 Grade A?
- Ex-stock about 5–7 days when plate is in yard. Standard mill rolling and normalize about 45–60 days. 3.2 inspection about 2 months.
- Can SHH STEEL issue EN 10204 3.2 for A662GRA?
- Yes. EN 10204 3.1 is standard. EN 10204 3.2 is arranged with SGS, TÜV, BV, ABS, CCS, DNV or the inspector named on the order.
Conclusion
ASTM A662 Grade A Steel Plate is C-Mn-Si vessel plate for moderate and lower temperature welded service, with 400–540 MPa tensile, 275 MPa yield and mandatory normalize. Whether the inquiry says ASTM A662 Grade A, A662 Gr.A, A662GRA, A662-A, A662 Gr A or SA662 Grade A, SHH STEEL as a global steel mill sourcing partner and steel manufacturer & exporter (mill-direct, China origin) supplies plate with Grade A chemistry, heat and product analysis as ordered, recorded normalize, and EN 10204 3.1 or 3.2 certification.
SHH STEEL supplies ASTM A662 Grade A / A662 Gr.A Low Temp Vessel Plate to the United States, Europe, the Middle East, Africa, Asia and the Americas for work that actually names this grade.
Contact SHH STEEL for mill rolling, dual SA-662 marking, cutting, bevel, 3.2 inspection or a worldwide quotation.
ASTM A662 Grade A Steel Plate, A662 Gr.A, A662GRA, SA662 Grade A, C-Mn-Si vessel plate, A662 Grade A supplier, SHH STEEL




