ASME SA612 and SA516 Gr. 70 are both fine-grained, killed carbon-manganese-silicon pressure-vessel steel plates, but ASME SA612 is specifically optimized for lightweight, thin-walled pressure equipment applications. It is the preferred grade for low- and medium-pressure thin-walled vessels and boiler components.
In contrast, the core advantage of SA612 lies in its suitability for thin-walled, lightweight designs. With a standard maximum thickness of 25 mm, it allows for significantly reduced plate wall thickness under the same design pressure conditions, effectively lowering the equipment's dead weight, reducing raw material consumption and welding labor hours, and resulting in more favorable overall manufacturing costs.
Under equivalent pressure conditions, ASME SA612 allows for the use of thinner plates, reducing weight and resource consumption while shortening welding and fabrication cycles. With excellent weldability and optional low-temperature impact performance at -40°C, it is widely used in low-pressure gas storage cylinders, thin-walled heat exchangers, and small boiler drums.
For projects where equipment wall thickness is ≤25 mm, operation is at medium to low pressures, and the goal is to achieve lightweight construction and cost reduction, SA612 should be prioritized as a replacement for the general-purpose SA516 Gr.70, balancing performance and overall economic benefits.
| Item | SA612 (SA612M) | SA516 Gr.70 (SA516M Gr.70) |
|---|---|---|
| Standard | ASTM A612/A612M (ASME SA612) | ASTM A516/A516M (ASME SA516) |
| Material Type | High-strength carbon-manganese-silicon steel | Medium-carbon manganese steel (pressure vessel quality) |
| Delivery Condition | As-rolled, normalized, or stress-relieved | As-rolled, normalized, normalized & tempered, or quenched & tempered (per request) |
| Thickness Range | Standard: ≤25mm; Custom: up to 100mm | 6-300mm (common: 10-150mm) |
| Core Application | High-pressure, low-temperature pressure vessels, LNG storage | General-purpose pressure vessels, boilers, storage tanks (most versatile) |
Selecting the appropriate grade helps ensure safety, compliance, and the long-term reliability of equipment.Suppliers that meet these standards help reduce risks, avoid rework, and support the smooth execution of projects.
1. ASME SA612 vs SA516 Gr.70 Chemical Composition
| Element | ASME SA612 (Standard ≤25mm) | ASME SA516 Gr.70 (Standard ≤300mm) |
|---|---|---|
| Carbon (C) | ≤0.25 |
≤0.27 (≤12.5mm); ≤0.28 (12.5–50mm); ≤0.30 (50–300mm) |
| Manganese (Mn) | 1.00–1.50 | 0.85–1.20 |
| Silicon (Si) | 0.15–0.50 | 0.15–0.40 |
| Phosphorus (P) | ≤0.025 | ≤0.025 |
| Sulfur (S) | ≤0.025 | ≤0.025 |
| Chromium (Cr) | ≤0.30 | ≤0.25 |
| Nickel (Ni) | ≤0.30 | ≤0.25 |
| Molybdenum (Mo) | ≤0.08 | ≤0.08 |
| Copper (Cu) | ≤0.30 | ≤0.35 |
| Total Aluminum (Al) | ≥0.020 | ≥0.020 |
| Niobium (Nb) | ≤0.05 | ≤0.02 |
| Vanadium (V) | ≤0.08 | ≤0.03 |
2.ASME SA612 vs SA516 Gr.70 Mechanical Properties ( ASME Standard)
| Property | ASME SA612 | ASME SA516 Gr.70 |
|---|---|---|
| Standard Thickness Range | ≤25mm (1 inch) | 6–300mm (0.25–12 inches) |
| Tensile Strength (MPa) | 570–725 (≤12.5mm); 560–695 (12.5–25mm) | 485–620 (all thicknesses) |
| Yield Strength (0.2% offset, min MPa) | 345 (all thicknesses) | 260 (all thicknesses) |
| Elongation (200mm gauge length, min %) | 22 (≤12.5mm); 20 (12.5–25mm) | 21 (longitudinal); 17 (transverse) |
| Elongation (50mm gauge length, min %) | 16 (≤12.5mm); 15 (12.5–25mm) | 24 (longitudinal); 20 (transverse) |
| Charpy V-Notch Impact Toughness |
No mandatory standard requirement; -40℃ ≥27J available on request |
Mandatory requirement: -29℃ ≥27J (standard); -46℃ ≥27J (low-temperature grade) |
| Brinell Hardness (max HB) | ≤197 | ≤187 |
| Carbon Equivalent (CEV, max) | ≤0.45 | ≤0.43 |
3.ASME SA612 vs SA516 Gr.70 Thickness Range
ASME SA612
Standard Specification Limitations: The maximum applicable thickness is 25 mm; plates exceeding 25 mm cannot be supplied as standard SA612 material.
Standard Stock and Production Range: 6 mm – 25 mm; a full range of thin-wall dimensions is available for standard orders.
Custom-made plates with thicknesses exceeding 25 mm: These do not comply 777777.NHBMNMN , , with the ASME SA612 base standard and are available only through special technical certification; they are rarely used in pressure vessel projects.
ASME SA516 Gr. 70
There is no upper thickness limit specified in the standard; the industrial supply range covers 6 mm to 300 mm, including thin plates, medium plates, and thick plates.
All thickness specifications are available for stable, batch production with ample inventory to meet the demand for both small thin plates and heavy-duty thick plates.
ASME SA612 steel plates Thickness Range
4.ASME SA612 vs SA516 Gr.70 Heat Treatment Conditions for Delivery
ASME SA612
This standard does not specify mandatory heat treatment; the default delivery condition for general orders is as-rolled (AR).
The following optional delivery conditions are available upon customer request: normalized (N), normalized and tempered (N+T), and stress-relieved (SR)
Recommendation: If a -40°C Charpy V-notch impact test is required under low-temperature operating conditions, select the normalized delivery condition.
ASME SA516 Gr.70
Steel plates thicker than 40 mm must undergo normalizing treatment to ensure uniform internal microstructure and stable low-temperature toughness.
Steel plates with a thickness of ≤40 mm may be supplied in the as-rolled condition without impact toughness requirements.
Available supply conditions: as-rolled (AR), normalized (N), designated as SA516 Gr.70N
Recommendation: If impact toughness at -29°C or -46°C is required, the material must be supplied in the normalized condition, as impact toughness is a mandatory standard requirement for SA516 Gr.70 in the normalized condition.
ASME SA612 steel plates Production Process
SA612's Exclusive Advantages by Industry
- Fine Chemicals / Coal Chemicals High-Pressure Reaction Units: Hydrogenation, ammonia synthesis, and alkylation reactors
- Small-Scale Cryogenic Gas Storage: Small-scale pressure buffer tanks for liquid nitrogen and liquefied petroleum gas
- Offshore Platform Skid-Mounted Equipment: Compact high-pressure separation modules (reducing weight and hoisting costs)
- Mobile Pressure Vessels: Vehicle-mounted / ship-mounted high-pressure cylinder assemblies, mobile pressure testing vessels
- Medium- and High-Pressure Heat Exchangers: Shell-and-tube high-pressure condensers, high- and low-pressure liquid separators
SA516 Gr.70 General-Purpose Mainstream Industries
- Large-Scale Storage Equipment for Oil Refining: Large vertical / spherical atmospheric storage tanks for crude oil, LPG, and liquid ammonia
- Thermal Power / Cogeneration Boiler Systems: Steam drums, feedwater heaters, steam pipe shells
- General Chemical Distillation Units: Atmospheric / low-pressure distillation columns, general-purpose heat exchangers
- Water Treatment and Municipal Pressure Vessels: Desalination equipment, large-capacity pressurized water purification tanks
- Conventional Cryogenic Storage Tanks (≥-30°C): Large-capacity atmospheric LPG storage tanks
Direct Comparison: When to Choose Which?
| Decision Factor | Choose ASME SA612 | ASME SA516 Gr 70 |
|---|---|---|
| Design Pressure | High (≥10 MPa) | Medium (2-10 MPa) |
| Service Temperature | -40°C to 300°C | -10°C to 400°C |
| Cost Sensitivity | Low (prioritize performance) | Medium (balance cost & performance) |
| Key Requirement | Low-temperature toughness + high strength | Versatility + weldability |
ASME SA612 is the top choice for high-pressure, low-temperature, safety-critical projects (e.g., LNG, offshore) where strength and toughness are non-negotiable.
ASME SA516 Gr 70 is the most cost-effective all-around solution for most pressure vessel applications, offering broad compatibility with global standards and processing requirements.
When to select ASME SA612:
High design pressure, but wall thickness needs to be controlled (typically within 25 mm).
Equipment that needs to be moved frequently (such as tank trucks) and is highly sensitive to its own weight.
High strength guaranteed in the normalized condition.
When to select ASME SA516 Gr 70:
Wall thickness exceeds 25 mm.
The project is highly sensitive to material costs (SA516 is typically slightly less expensive than SA612 and is more readily available in stock).
Conventional, stationary large storage tanks or reactors.
A simpler welding procedure qualification is required (SA516 is extremely widespread, and most factories have established data available).
Click to view SA612 inventory status
ASME SA612 Standard Stock Inventory List
|
Plate Thickness (mm) |
Standard Width Range (mm) |
Standard Length Range (mm) |
Minimum Stock Tonnage (MT) |
|---|---|---|---|
|
8 |
1500 / 1800 |
6000 / 8000 |
≥ 50 |
|
10 |
1500 / 1800 |
6000 / 8000 |
≥ 80 |
|
12 |
1500 / 2000 |
6000 / 9000 |
≥ 100 |
|
14 |
1500 / 2000 |
6000 / 9000 |
≥ 60 |
|
16 |
1500 / 2000 |
6000 / 10000 |
≥ 120 |
|
20 |
1800 / 2200 |
6000 / 10000 |
≥ 150 |
|
25 |
1800 / 2200 |
6000 / 10000 |
≥ 80 |
|
30 – 50 |
2000 / 2500 |
6000 / 12000 |
Subject to real-time stock confirmation |
Customized sizes and special lengths are available upon customer request. All products comply with ASME SA612 standard for pressure vessel service.
GNEE is a professional manufacturer and exporter of ASTM A612/A612M,ASME SA612/SA612M pressure vessel steel plates, with extensive experience serving global customers in the cryogenic and medium-pressure industrial sectors. Whether you need standard or custom products, we provide high-quality products and professional services to help you reduce costs and improve project efficiency.
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our Real-World Case Studies
Case 1: LNG Storage Tanks in Australia
Client: Leading LNG Export Terminal
Challenge:
Build 160,000m³ LNG tanks (-165°C) with inner shell support structures requiring -45°C impact toughness.
Budget constraints demanded cost-effective alternatives to 9% Ni steel.
Solution:
Inner supports: ASTM A612 PVQ plates (thickness: 50mm) with Charpy V-notch testing @ -45°C.
Welding: Submerged arc welding (SAW) with AWS A5.23 EM12K wire.
Result:
Saved $1.2M vs using 9% Ni steel for non-cryogenic zones.
Passed 100% UT and MT inspections (ASME BPV Code Case 2596).
Case 2: Hydrogen Reactor in Germany
Client: Green Hydrogen Startup
Challenge:
Fabricate a 12MPa hydrogen reactor operating at 300°C with cyclic loading.
Required material with H₂ embrittlement resistance under PED 2014/68/EU.
Solution:
Shell material: A612 PVQ (80mm thickness) + NACE TM0284 HIC testing.
Post-weld heat treatment (PWHT): 620°C ×4h to relieve residual stresses.
Result:
Achieved 30-year design life certification by TÜV SÜD.
Reduced total weight by 15% vs A516 Gr.70.
FAQ:
What is the difference between ASTM A612 and ASME SA612?
There is no fundamental difference. SA612 is the designation in the ASME specification, and its technical content is completely identical to ASTM A612, applicable to the manufacture of pressure vessels for ASME certification.
What is the composition of ASTM A612?
What is the composition of ASTM A612? ASTM A612 steel plate is a high-strength low-alloy (HSLA) steel plate designed for welded pressure vessels. It has a nominal composition of carbon, manganese, phosphorus, sulfur, silicon, nickel, chromium, molybdenum, and copper.
What is ASTM A516 Grade 70 material?
ASTM A516 Gr 70 Rolled Plate is a medium carbon alloy that contains manganese, phosphorus, sulfur, and silicon. These added alloying elements provide increased strength and versatility in highly demanding applications such as pressure vessels requiring moderate to lower temperatures where notch toughness is essential.
What Are the Equivalent Grades of SA612/A612 in Chinese and European Standards? Can They Be Used as Direct Substitutes?
Common approximate equivalent grades include EN P355GH, DIN 1.0473, and GB Q345R. However, they cannot be used as direct equivalents. Their suitability must be confirmed in accordance with design specifications and approval requirements.
Which Is More Suitable for Low-Temperature Applications: SA612 or SA516 Gr.70?
SA612 delivers more stable comprehensive performance in thick plate and high-stress working conditions, whereas SA516 Gr.70 offers better cost-effectiveness in conventional operating conditions.