ASTM A387 steel plate is a chromium-molybdenum alloy steel specifically designed for pressure vessels and boilers operating at elevated temperatures.
As a professional pressure vessel steel plate manufacturer and exporter, GNEE supplies a full range of ASTM A387 grades for high-temperature and high-pressure industrial applications.
ASTM A387 steel plate
Within the first 100 words, it is important to clarify that GNEE is a manufacturer-oriented supplier, working with stable mills and strict quality control systems.
ASTM A387 steel plates are widely used in oil & gas, petrochemical, refinery, and power generation industries where long-term reliability under heat and pressure is critical.
ASTM A387 steel plate includes Grade 5, Grade 9, Grade 11, Grade 12, and Grade 22, and each grade is divided into Class 1 and Class 2, based on different strength and heat treatment requirements.
ASTM A387 Steel Plate Grades and Classification
ASTM A387 steel plates are classified according to their chromium and molybdenum content, which directly affects heat resistance, corrosion resistance, and creep strength.
Available grades include:
ASTM A387 Grade 5
ASTM A387 Grade 9
ASTM A387 Grade 11
ASTM A387 Grade 12
ASTM A387 Grade 22
Each grade is supplied in:
Class 1: Lower strength, better formability
Class 2: Higher strength, improved load-bearing performance
This classification allows engineers to select the most suitable material based on operating temperature, pressure level, and fabrication requirements.
ASTM A387 Steel Plate Chemical Composition Table
The chemical composition of ASTM A387 steel plates is carefully controlled to balance strength, toughness, and resistance to oxidation and corrosion.
Chemical Composition (%)
| ASTM A387 | Grade 5 | Grade 9 | Grade 11 | Grade 12 | Grade 22 |
|---|---|---|---|---|---|
| Carbon | 0.15 max | 0.15 max | 0.04–0.17 | 0.04–0.17 | 0.04–0.15 |
| Manganese | 0.25–0.66 | 0.25–0.66 | 0.35–0.73 | 0.35–0.73 | 0.25–0.66 |
| Phosphorus | 0.035 | 0.030 | 0.035 | 0.035 | 0.035 |
| Sulfur | 0.030 | 0.030 | 0.035 | 0.035 | 0.035 |
| Silicon | 0.55 max | 1.05 max | 0.44–0.86 | 0.13–0.45 | 0.50 max |
| Chromium | 3.9–6.1 | 7.9–10.1 | 0.94–1.56 | 0.74–1.21 | 1.88–2.62 |
| Molybdenum | 0.40–0.70 | 0.85–1.15 | 0.40–0.70 | 0.40–0.65 | 0.85–1.15 |
Mechanical Properties of ASTM A387 Steel Plate
ASTM A387 steel plates are designed to maintain mechanical stability in temperature ranges from 316°C to 593°C.
Mechanical Properties (Summary)
| Grade | Class | Tensile Strength (MPa) | Yield Strength (MPa) | Elongation (50mm %) |
|---|---|---|---|---|
| Grade 5 | Class 1 | 415–585 | 205 | 18 |
| Grade 5 | Class 2 | 515–690 | 310 | 18 |
| Grade 9 | Class 1 | 415–585 | 205 | 18 |
| Grade 9 | Class 2 | 515–690 | 310 | 18 |
| Grade 11 | Class 1 | 415–585 | 240 | 22 |
| Grade 11 | Class 2 | 485–620 | 310 | 22 |
| Grade 12 | Class 1 | 380–550 | 230 | 22 |
| Grade 12 | Class 2 | 450–585 | 275 | 22 |
| Grade 22 | Class 1 | 415–585 | 205 | 18 |
| Grade 22 | Class 2 | 515–690 | 310 | 18 |
These properties ensure excellent resistance to deformation, cracking, and creep under long-term thermal stress.
Applications of ASTM A387 Steel Plate in High-Temperature Service
ASTM A387 steel plates are widely applied in environments requiring both heat resistance and pressure-bearing capability.
- Typical applications include:
- Pressure vessels and reactors
- Industrial boilers and boiler drums
- Heat exchangers and condensers
- Oil & gas transportation systems
- Sour oil and gas processing equipment
- Grade selection guidance:
- Grade 5 & Grade 9: High chromium content, suitable for sour oil and gas environments
- Grade 11 & Grade 12: Balanced composition, widely used in welded pressure vessels and industrial boilers
- Grade 22: Enhanced creep strength for higher-temperature applications
As an experienced manufacturer and exporter, GNEE supplies ASTM A387 steel plate covering Grade 5, Grade 9, Grade 11, Grade 12, and Grade 22 with full certification and stable quality. Our chromium-molybdenum alloy steel plates are engineered for safe and long-term service in pressure vessel and boiler applications.
Contact us for the latest ASTM A387 steel plate price list, grade selection support, and technical documentation.
Contact us for latest ASTM A387 steel plate price list
What is ASTM A387 material?
ASTM A387 GR. 91 CL. 2 Alloy Steel Plates manufactured at the world's finest steel mills, this molybdenum-chrome based alloy has excellent resistance to greater working temperatures, making it the right selection for various applications like in gas, oil, chemical, and power generation.
What is ASTM A387 Grade 11 equivalent to?
ASTM A387 grade 11 equivalent steel is ASME SA387 grade 11. ASTM A387 grade 11 covers A387 grade 11 class 1 and A387 grade 11 class 2, which are equivalent to ASME SA387 grade 11 class 1 and SA387 grade 11 class 2 respectively.
What is the difference between ASTM A182 and A387?
A387 is Plate material. A182 is Forging material. You can refer relevant ASTM Book of standards.
What is ASTM A387?
The ASTM A387 specification is the Standard Specification for Pressure Vessel Plates, Alloy Steel, Chromium-Molybdenum plates used in the application of welded boilers and pressure vessels subjected to elevated temperatures. The two grades SSAB produces are available as Class 1 and/or Class 2.