ASTM A515/A515M is the standard specification by ASTM International covering carbon-silicon steel plates intended primarily for intermediate and higher-temperature service in welded boilers and other pressure vessels. The specification defines three grades — Grade 60, Grade 65, and Grade 70 — with increasing strength levels. The companion specification ASME SA-515 adopts identical requirements for ASME Boiler and Pressure Vessel Code (BPVC) compliance, making it the reference standard for Code-stamped boiler and pressure vessel construction.

Zhengzhou Huitong (HT Pipe) supplies ASTM A515 / SA-515 pressure vessel plates in all three grades with full Mill Test Certificates (MTC) per EN 10204 3.1. 

1. Standard Scope & Designation

ASTM A515/A515M applies to plates fabricated by any manufacturing process and covers plates for use in welded pressure vessels where the service temperature is in the intermediate to higher range. Killed steel with a coarse austenitic grain size practice is mandatory to ensure adequate notch toughness and creep resistance.

2. Grades Covered by ASTM A515

ASTM A515 defines three carbon-silicon grades with increasing minimum tensile strength. Grade 70 is the most common for high-temperature boiler construction; Grade 60 is used for lower-pressure, lower-temperature boiler applications.

3. Chemical Composition (ASTM A515 Table 1)

Values are maximum unless shown as a range. Heat analysis. Per ASTM A515/A515M-17. Killed steel, coarse austenitic grain size practice required.

Note: Full chemistry ranges per ASTM A515/A515M-17 Table 1. Steel shall be made by open-hearth, basic-oxygen, or electric furnace. Product analysis tolerances per ASTM A20/A20M apply.

4. Mechanical Property Requirements (ASTM A515 Table 2)

All values are minimum unless shown as a range. Per ASTM A515/A515M-17. Testing per ASTM A20/A20M and ASTM A370.

Note: Elongation in 8" gauge length (200 mm) uses a rectangular specimen; elongation in 2" (50 mm) uses the standard round specimen per ASTM A370. Both must be met when applicable.

5. Heat Treatment Requirements

6. Testing & Inspection Requirements

7. Plate Dimensions & Tolerances

ASTM A515 plates are produced by hot rolling. Common dimensional ranges from mill production:

Note: Thickness tolerances per ASTM A20/A20M Table 1 (typically ±0.3 mm for plates under 40 mm). Width and length tolerances per ASTM A480/A480M. Mill edge may extend up to 40 mm beyond nominal width.

8. Industries & Applications

9. ASTM A515 vs ASTM A516 vs ASTM A387 — Pressure Vessel Plate Comparison

10. Related Standards

11. How to Order — Required Information

12. Frequently Asked Questions

Q: What is ASTM A515 Grade 70 plate used for?

ASTM A515 Grade 70 is the most widely used grade in the A515 family for power boiler construction and high-temperature pressure vessels. Key applications include power boiler shells and drums, reformer furnace tubesheets and shells, ammonia synthesis converters, catalytic cracking unit vessels, and high-temperature process reactors in petroleum refining and petrochemical plants. Its minimum tensile strength of 485 MPa and yield of 260 MPa, combined with adequate creep resistance at elevated temperatures, make it suitable for pressure vessel design temperatures in the 425–540°C range per ASME BPVC Section I and Section VIII.

Q: What heat treatment is required for ASTM A515 plates over 2 inches (50 mm)?

Plates over 50 mm (2 inches) thickness must be normalized — heated above the upper critical temperature (approximately 900–940°C / 1650–1725°F), held for sufficient time to achieve uniform temperature through the plate thickness, then air cooled. This normalizing treatment refines the coarse as-cast microstructure from the steelmaking process into a fine, uniform ferrite-pearlite microstructure with improved strength, toughness, and dimensional stability. Normalization is particularly important for thick-section plates where slow cooling from hot rolling alone would produce a coarse, uneven grain structure with lower toughness.

Q: What is the difference between ASTM A515 and ASME SA-515?

Technically identical in chemical composition, mechanical properties, heat treatment, and testing requirements. ASME SA-515 is ASTM A515 adopted into ASME BPVC Section II Part A (Materials). The critical difference is regulatory: SA-515 is the mandatory specification for materials used in ASME Code-stamped pressure vessels (BPVC Section I for power boilers, Section VIII for pressure vessels). When purchasing plates for an ASME Code-stamped vessel, specify SA-515 to ensure compliance with authorized inspection requirements, CMTR documentation, and material traceability. Most mills supply dual-certified A515/SA-515 plates.

Q: Can ASTM A515 be used for cryogenic or low-temperature service?

ASTM A515 is not recommended for low-temperature service. The coarse austenitic grain size practice and relatively high carbon content (up to 0.35% for Grade 70) result in poor notch toughness at low temperatures — the plate becomes susceptible to brittle fracture. For pressure vessels requiring notch toughness below approximately 0°C (32°F), specify ASTM A516 instead, with supplementary Charpy V-notch impact testing (Supplementary Requirement S5 in ASTM A20/A20M) at the design minimum temperature. A516 Grade 60 or 70 with confirmed impact energy provides reliable service down to at least −50°C.

Q: What is the maximum allowable stress for ASTM A515 Grade 70 at elevated temperatures?

Per ASME BPVC Section II Part D (2023 edition), the allowable tensile stress for ASTM SA-515 Grade 70 at key temperatures is approximately: 20°C (68°F) — 113 MPa (16,400 psi); 300°C (570°F) — 113 MPa; 400°C (750°F) — 113 MPa; 450°C (840°F) — 103 MPa; 500°C (930°F) — 85 MPa; 540°C (1000°F) — 73 MPa. Above approximately 540°C, creep deformation controls the design, and chrome-moly steels (ASTM A387 Grade 11 or 22) with superior creep resistance become necessary. Always use the latest ASME BPVC Section II Part D tables for design calculations.

Request a Quote — ASTM A515 / SA-515 Pressure Vessel Plate

Zhengzhou Huitong (HT Pipe) supplies ASTM A515 / SA-515 Grade 60, 65, and 70 pressure vessel plates in all standard thicknesses. Full EN 10204 3.1 CMTRs, competitive pricing, and mill-direct delivery from major Asian steel mills.