A387 Grade 12 Class 1 is a chromium‑molybdenum alloy steel plate designed for high‑temperature and high‑pressure service, commonly used in petrochemical units, refinery equipment, and thermal power systems. The steel offers stable performance under elevated temperatures due to its Cr‑Mo alloy design, providing improved oxidation resistance, creep strength, and long‑term structural reliability. Its balanced composition ensures good weldability and uniform mechanical behavior, making it suitable for pressure‑bearing components in demanding operating environments.

Chemical Composition

A387 Grade 12 Class 1 contains Cr (0.80–1.25%) and Mo (0.45–0.65%), forming the core of its high‑temperature strength and oxidation resistance. Carbon is controlled to maintain weldability, while manganese and silicon support structural stability. Phosphorus and sulfur are strictly limited to ensure clean steel quality and reduce cracking risk during fabrication.

Mechanical Properties

The grade provides a minimum tensile strength of 415 MPa and yield strength around 240 MPa, depending on thickness and delivery condition. It maintains reliable creep resistance and stable mechanical behavior under long‑term exposure to elevated temperatures, supporting safe operation in pressure‑bearing systems.

Size Range (Website 5 Standard Template)

Thickness: 3–150 mm Width: 1220–4200 mm Length: 5000–18000 mm

Stock & Processing Services

Cutting • Beveling • Welding preparation • Heat treatment • Customized fabrication Plates can be supplied in normalized or tempered conditions depending on project requirements.

Applications

• High‑temperature pressure vessels

• Petrochemical reactors and furnace components

• Refinery equipment and hydrogenation units

• Thermal power plant piping and boilers

• Heat‑exchanger shells and high‑pressure components

Certification & Service

Material supplied according to ASTM A387 requirements with mill test certificates. Technical support available for material selection, welding procedures, and project specifications.