Pressure Vessel Plates, Carbon Steel, for Intermediate- and Higher-Temperature Service

A515/A515M: Standard Specification for Pressure Vessel Plates, Carbon Steel, for Intermediate- and Higher-Temperature Service

When designing and fabricating pressure vessels intended for demanding operational environments, selecting the correct materials is paramount. ASTM A515/A515M provides an essential foundation for engineers and manufacturers, ensuring the reliability and safety of equipment subjected to elevated temperatures. This industry-leading standard specifies the requirements for carbon steel plates specifically engineered for such critical applications.

What is A515/A515M?

ASTM A515/A515M is an authoritative standard that defines the material properties and manufacturing requirements for carbon steel plates designed for use in welded boilers and other pressure vessels operating at intermediate and higher temperatures. Originating from ASTM International, this specification ensures that the steel possesses the necessary strength and ductility to withstand the stresses and thermal cycles inherent in such services.

Scope & Purpose

This comprehensive standard governs the composition, mechanical properties, and manufacturing practices for carbon steel plates intended for pressure vessel construction. It specifies three distinct grades (60, 65, and 70) with varying strength levels, catering to different design pressures and operational demands. The scope includes plates up to a specified maximum thickness, beyond which specific considerations may apply. While it details the core requirements, it explicitly defers to ASTM A20/A20M for general requirements, testing procedures, and permissible variations, creating a layered approach to material specification.

Who Must Comply?

• • Primary audience: Materials Engineers, Mechanical Engineers, Pressure Vessel Designers, Quality Control Inspectors, Procurement Specialists, and Fabricators.
• • Industries affected: Pressure Vessel Manufacturing, Chemical Processing, Petrochemical, Power Generation, Oil and Gas, and Shipbuilding.
• • Compliance nature: While often a voluntary industry standard, compliance becomes mandatory when specified in engineering designs, purchase orders, or by regulatory bodies and codes (e.g., ASME Boiler and Pressure Vessel Code, which references this standard as SA-515/SA-515M).
• • Enforcement: Compliance is typically enforced through material testing, mill certifications, third-party inspections, and audits by clients or regulatory agencies.

Key Requirements Overview

The standard requires that the carbon steel be produced using a killed steelmaking practice to ensure homogeneity and a coarse austenitic grain size for improved high-temperature performance. Professionals must ensure that the plates conform to specific chemical compositions, particularly regarding carbon, manganese, phosphorus, sulfur, and silicon content, which are critical for high-temperature strength and weldability. Key provisions include meeting defined tensile strength and minimum yield strength requirements, as well as specified elongation percentages, which are crucial indicators of ductility. Furthermore, the standard mandates heat treatment requirements, with plates over 2 inches (50 mm) in thickness typically requiring normalization to achieve the desired microstructure and mechanical properties.

Related Standards & References

ASTM A515/A515M is intrinsically linked with ASTM A20/A20M, Specification for General Requirements for Steel Plates for Pressure Vessels. A20/A20M provides the overarching framework for testing, quality control, and dimensional tolerances that apply to all pressure vessel plate specifications, including A515/A515M. Additionally, standards such as ASTM A435/A