A387 Grade 5 Class 1 is a 0.5Cr‑0.5Mo alloy pressure vessel steel plate designed for medium‑temperature hydrogen service and refinery equipment.
It provides reliable resistance to hydrogen attack, stable creep strength, and consistent performance in petrochemical environments operating up to approximately 450–550°C.
The steel is supplied in normalized and tempered condition to ensure uniform microstructure and dependable weldability for large‑scale pressure vessels.
Chemical Composition (ASTM A387)
Carbon: ≤ 0.15%
Manganese: 0.30–0.60%
Silicon: 0.50–1.00%
Chromium: 0.40–0.65%
Molybdenum: 0.45–0.60%
Phosphorus: ≤ 0.035%
Sulfur: ≤ 0.035%

The Cr‑Mo alloy system provides oxidation resistance and long‑term stability under hydrogen exposure.

Mechanical Properties
Yield Strength: ≥ 205 MPa
Tensile Strength: 415–550 MPa
Elongation: ≥ 20%
Impact Energy: ≥ 55 J (room temperature)

These values support safe operation in hydrogen reactors and refinery pressure systems.

Size Range (Website 5 Standard Template)
Thickness: 3–150 mm  
Width: 1220–4200 mm  
Length: 5000–18000 mm

Stock & Processing Services
Cutting • Beveling • Heat treatment • Welding preparation • Custom fabrication for pressure vessels

Applications
Hydrogenation reactors
Refinery pressure vessels
High‑temperature petrochemical equipment
Heat exchangers and boilers