SA387 Gr22 Cl2 and 15CrMoR are both high-temperature chromium-molybdenum (Cr-Mo) alloy steels for pressure vessels, but the key difference is their standard, with SA387 being an ASTM/ASME standard (US), while 15CrMoR is a Chinese GB/T standard (China), with similar properties but distinct designation systems and slight composition/mechanical spec variations, making them functionally interchangeable for many high-temp services like boilers & heat exchangers.
SA387 Grade 22 Class 2
Standard: ASME SA387 / ASTM A387
Alloy system: 2.25% Cr – 1.0% Mo
Class 2: Normalized and tempered (N+T)
Widely used in ASME-coded pressure vessels
15CrMoR
Standard: GB/T 713 (China pressure vessel steel)
Alloy system: 1.0–1.5% Cr – 0.45–0.65% Mo
Typically supplied in normalized or normalized & tempered condition
Commonly used in Chinese domestic and export boiler projects
SA387 Gr22 CL2 is generally specified for international and ASME projects, while 15CrMoR is more common in China-based equipment manufacturing.
Chemical Composition Comparison
Typical chemical composition (wt.%):
| Element | SA387 Gr22 CL2 | 15CrMoR |
|---|---|---|
| Carbon (C) | ≤ 0.15 | ≤ 0.18 |
| Chromium (Cr) | 2.00 – 2.50 | 1.00 – 1.50 |
| Molybdenum (Mo) | 0.90 – 1.10 | 0.45 – 0.65 |
| Manganese (Mn) | 0.30 – 0.60 |
0.40 – 0.70 |
Mechanical Properties
SA387 Grade 22 Class 2
Tensile Strength: 515 – 690 MPa
Yield Strength (min): 310 MPa
Elongation: ≥ 18%
15CrMoR
Tensile Strength: 440 – 640 MPa
Yield Strength (min): 295 MPa
Elongation: ≥ 19%
Although both materials meet pressure vessel strength requirements, SA387 Gr22 CL2 offers better high-temperature strength stability, making it more suitable for long-term severe service.
Typical Applications
SA387 Gr22 CL2 Applications
Petrochemical reactors
High-temperature boilers and steam drums
Hydrogenation vessels
Refinery pressure vessels
High-pressure heat exchangers
15CrMoR Applications
Power plant boilers
Medium-temperature pressure vessels
Heat exchangers
Chemical processing equipment
Material selection should always align with design temperature, pressure, and code requirements.
SA387 Gr22 CL2 vs 15CrMoR: How to Choose
Choose SA387 Gr22 CL2 if:
Project follows ASME / ASTM standards
Operating temperature is very high
Hydrogen resistance and creep strength are critical
Long-term reliability is required
Choose 15CrMoR if:
Project follows GB/T standards
Operating temperature is moderate-high
Cost efficiency is a key concern
Why Choose GNEE Steel
GNEE Steel supplies both SA387 Gr22 CL2 and 15CrMoR pressure vessel steel plates with:
Full compliance with ASME, ASTM, and GB standards
Thickness range from 6mm to 150mm
EN 10204 3.1 / 3.2 MTC
Third-party inspection (SGS, BV, TUV)
Technical support for material selection and equivalency
Conclusion
While SA387 Gr22 CL2 and 15CrMoR are both Cr-Mo pressure vessel steels, they serve different standards, temperature ranges, and project requirements. Understanding their differences is essential for safe, economical, and code-compliant equipment design.
📩 Contact GNEE Steel today for expert advice, competitive pricing, and reliable supply of pressure vessel steel plates for your boiler and petrochemical projects.
What is the difference between SA 387 Grade 11 CL 1 and Class 2?
The difference between SA 387 Grade 11 Class 1 and Class 2 Plate lies in their mechanical properties. However, they both have the same chemical composition. The tensile strength and yield strength of class 2 material is higher than that of class 1, whereas the elongation for class 1 is higher compared to class 2.
What is SA 387 GR 22 material?
SA 387 Grade 22 Steel Plate
The SA 387 Grade 22 Steel is a pressure vessel steel made up of high-quality raw material and high technology. Commonly used for high-temperature tasks based on its high heat tolerance this steel plate can be exposed up to 600° while maintaining superb oxidation and corrosion resistance.
What is the difference between 15CrMoR steel and 15CrMo material?
15CrMoR steel generally refers to steel plate, the material is 15CrMo material, the following R is the abbreviation of the word "capacity" for container plate, and the one without letter after 15CrMo material only refers to the alloy structural plate made of 15CrMo material.
15CrMoR steel plate is used for medium temperature pressure vessel. There are also 15CrMoR steel plate in the presence of hydrogen. It is mainly used on petrochemical equipment. When implementing the standard GB713, the corresponding American grade is SA387gr12 series, which is delivered in the normalized + tempered state. The flaw detection standard is implemented according to JB / T4730.3. The sulfur (S) and phosphorus (P) contents can also be controlled according to the customer's needs, and the high temperature tensile test can be carried out.
What kind of material is 15CrMoR steel plate
15CrMoR is steel for pressure vessels. It is a medium-temperature hydrogen-resistant steel.15CrMoR steel adds Cr, Mo and other alloying elements to low carbon steel, which greatly improves the overall performance of the steel. It has good high-temperature mechanical properties, high-temperature oxidation resistance, corrosion resistance, good toughness, process performance and weldability, so it is widely used in the manufacturing of petrochemicals, coal conversion, nuclear power, steam turbine cylinders, thermal power and other usage conditions Large equipment with harsh and complex corrosive media.
