A204 grade B Pressure Vessel Steel

ASTM A204 Grade B is a molybdenum-alloy pressure-vessel steel plate specified for welded boilers and other high-temperature, high-pressure equipment. Grade B offers a balance of strength and toughness for welded fabrication in pressure-retaining applications and is supplied in the as-fabricated condition unless otherwise specified.

Key features

• Conforms to ASTM A204 specification for molybdenum alloy steel plates for pressure vessels and boilers (available in Grades A, B and C).
• Mechanical properties (typical / per specification): tensile strength around 620 MPa and specified yield strength of 275 MPa (both referenced at 20°C).
• Chemical system: alloyed primarily with molybdenum; composition also includes carbon, silicon, manganese, phosphorus and sulfur and otherwise meets the chemical requirements of ASTM A204.
• Supplied as flat plates suitable for welding and fabrication; delivered in the as-fabricated condition unless heat treatment is requested.

Typical applications

• Boiler shells and headers
• High-temperature pressure vessels
• Heat exchangers and related welded fabrications where elevated-temperature strength and creep resistance are required

Supply and quality options

• Available as cut-to-size plates; please specify thickness, width, length and surface finish when inquiring.
• Standard documentation available on request: Mill Test Certificate (MTC), chemical analysis, tensile/yield test reports and heat numbers for traceability.
• Can be supplied with additional processing (stretcher leveling, edge trimming, beveling) or third-party inspection if required.

What to provide when requesting a quote

• Required grade (this listing: ASTM A204 Grade B)
• Exact plate dimensions (thickness × width × length) and quantity
• Required certifications or inspection (MTC EN 10204 3.1/3.2, third-party inspection)
• Delivery terms and packing preferences

If you need detailed chemical compositions, heat-treatment conditions, specific mechanical property certificates, or logistics options, please include those requirements in your inquiry so we can provide an exact commercial offer and lead time.