Boiler and Pressure Vessel Steel Plate: Grades, Properties and Applications

Pressure vessels, boilers, heat exchangers and storage tanks are not built from ordinary structural steel. They demand pressure vessel steel plate — material with guaranteed mechanical properties, controlled chemistry and documented quality that can safely contain pressure at operating temperature.

This guide explains the main boiler and pressure vessel plate grades, the properties that matter, the testing required, and how to specify the right material for your project.

Why Pressure Vessel Plate Is Different

Pressure vessel steel plate must withstand internal pressure, often at elevated temperature, without failing. Compared with structural plate, it has:

• Guaranteed tensile and yield strength over a defined temperature range;
• Controlled chemistry for weldability and consistent properties in thick sections;
• Guaranteed impact toughness (often at specified test temperatures);
• Full traceability — each plate is identified by heat number and tested, with results recorded on the mill test certificate.

The consequences of failure are severe, which is why this material is strictly specified, tested and certified.

Common Pressure Vessel Plate Grades

ASTM standards (widely used internationally)

• ASTM A516 — carbon steel plate for moderate- and lower-temperature service. Grades 55, 60, 65, 70 are the most common. A516 Gr.70 is arguably the most widely used pressure vessel plate in the world, used for boilers, pressure vessels, and storage tanks operating down to about -30°C.
• ASTM A387 — chromium-molybdenum alloy plate for elevated-temperature and high-pressure service (Grades 5, 11, 12, 22). Used for hydrogen service, reactors and high-temperature vessels.
• ASTM A537 — heat-treated carbon-manganese-silicon plate for pressure vessels in moderate and lower temperature service.

EN standards (Europe and global projects)

• EN 10028-2 P265GH / P295GH / P355GH — pressure vessel plate for elevated-temperature service. P265GH and P295GH are the most common for general boiler and vessel construction.
• EN 10028-3 P275NH / P355NH — normalized grades for lower-temperature service with improved toughness.

GB standards (China)

• Q245R / Q345R / Q370R — Chinese pressure vessel plate (R = 容器/ressure vessel). Q345R is the Chinese workhorse equivalent to P295GH/A516 Gr.65-70 in many applications.
• 15CrMoR / 14Cr1MoR — chromium-molybdenum grades for high-temperature service.

Key Properties to Specify

When you order pressure vessel plate, specify more than the grade:

• Thickness and dimensions — properties are thickness-dependent; thicker plates require different heat treatment and may have different guaranteed values;
• Impact test temperature — specify the required Charpy V-notch test temperature (e.g., 0°C, -20°C, -40°C) and energy level;
• Ultrasonic testing (UT) — for internal soundness, usually per a standard such as ASTM A435 or EN 10160;
• Heat treatment condition — as-rolled, normalized, quenched-and-tempered (QT), or thermomechanically processed, depending on grade and thickness;
• Tolerances and edge condition — and whether the plate needs to be cut to size with certified edges.

How Pressure Vessel Plate Is Made

Pressure vessel plate starts as a slab from a steel mill with tight composition control, then is rolled to thickness and heat treated to develop the required structure and properties:

• Normalizing refines grain structure and improves toughness — common for A516, P265GH and thicker plates;
• Quenching and tempering (QT) develops higher strength with good toughness — used for A387, P355GH/QT and high-strength vessel grades;
• TMCP (thermomechanical controlled processing) gives high strength and toughness with excellent weldability for offshore and heavy-duty applications.

The mill test certificate records the chemistry and mechanical test results for each heat, giving you full traceability.

Applications

• Boilers — water tube and fire tube boiler drums and shells;
• Pressure vessels — process vessels, reactors, separators;
• Storage tanks — atmospheric and pressurized storage of liquids and gases;
• Heat exchangers — shells and channels;
• Pipeline components — headers, flanges, fittings;
• LPG / LNG equipment — low-temperature tanks and vessels (with appropriate low-temperature grades).

Buying Pressure Vessel Plate: Checklist

1. Confirm the code and standard your project must meet (ASME / PED / GB 150 and the specific material standard).
2. Specify impact requirements explicitly — test temperature and energy are project-critical.
3. Request UT testing if the application is high-pressure or safety-critical.
4. Demand full mill test certificates with heat numbers traceable to each plate.
5. Arrange third-party inspection (SGS, BV, TÜV, Intertek) for international projects — most pressure vessel buyers do.
6. Consider processing — pressure vessel shops often need plate cut to drawing, beveled or machined; an integrated supplier can deliver ready-to-weld plate.

Supply Pressure Vessel Plate with Full Documentation

SteelGuang supplies boiler and pressure vessel steel plate under ASTM (A516, A387), EN (P265GH, P295GH, P355GH) and GB (Q345R, Q245R) standards, in thicknesses from 6 mm to over 150 mm. As a self-owned factory we provide:

• Full mill test certificates and traceability;
• Third-party inspection support;
• In-house cutting (flame, plasma, laser) — including custom shapes and cut-to-size plate;
• Export-grade packaging for sea freight.

Whether you need a few plates for a boiler shop or regular supply for vessel fabrication, request a quotation with full documentation or review our steel products. Send your standard, grade and impact requirements and we will confirm supply and testing within 24 hours.