ASTM B535-06(2022)

Overview

ASTM B535-06(2022): Standard Specification for Nickel-Iron-Chromium-Silicon Alloys (UNS N08330 and N08332) Seamless Pipe and Tube outlines the technical requirements for nickel-iron-chromium-silicon alloys produced as seamless pipes and tubes. Developed by ASTM International, this standard applies to hot-finished and cold-finished products intended for use in high-temperature and general corrosive environments. Pipes and tubes must be supplied in the annealed condition and are commonly used where exceptional heat and corrosion resistance are essential.

Key characteristics of these alloys include high nickel and chromium content with silicon additions, which enhance oxidation and carburization resistance. This specification ensures material reliability and uniform quality for industries requiring robust performance in demanding applications.

Key Topics

• Material Scope: Covers seamless pipe and tube in UNS N08330 and UNS N08332 alloys.
• Heat Resistance: Specifies use in heat resisting applications and general corrosive service.
• Mechanical Properties: Sets requirements for tensile strength, yield strength, elongation, and hardness.
• Chemical Composition: Defines composition limits for elements such as nickel, iron, chromium, silicon, and others to ensure specified alloy characteristics.
• Manufacturing Conditions:
  • Pipes and tubes must be annealed.
  • Minimum final heat treatments are specified: 1900°F (1040°C) for UNS N08330 and 2100°F (1150°C) for UNS N08332.
• Grain Size: For UNS N08332, an average ASTM No. 5 grain size or coarser is required.
• Testing and Inspection:
  • Flattening test to evaluate ductility and soundness.
  • Each item must pass either a hydrostatic test or nondestructive electric test for integrity verification.
• Dimensional Tolerances: Specifies permissible variations in outside diameter and other critical geometry parameters.

Applications

The alloys specified by ASTM B535-06(2022) are widely used in environments where high temperature and corrosive conditions prevail:

• Petrochemical Processing: Seamless pipes and tubes are essential in plants processing acids, fuels, and chemicals due to their corrosion resistance.
• Power Generation: These alloys are used for boiler tubes, heat exchangers, and superheater tubes where thermal stability and oxidation resistance are needed.
• Refining & Chemical Industry: Ideal for service in furnaces, reactors, and other environments exposed to harsh chemicals and elevated temperatures.
• Industrial Heating Equipment: Especially suited for radiant tubes and other furnace components.

These applications benefit from the robust mechanical and chemical properties defined in the standard, ensuring facility safety, reliability, and long service life.

Related Standards

ASTM B535-06(2022) references and is associated with several other key documents:

• ASTM B829: General Requirements for Nickel and Nickel Alloys Seamless Pipe and Tube - provides detailed requirements on testing, analysis, and permissible variations.
• ASTM B899: Terminology Relating to Non-ferrous Metals and Alloys - standardizes the terminology used within ASTM B535 and related documents.
• ASME SB-535: Covers similar requirements and is referenced for applications related to the ASME Boiler and Pressure Vessel Code.

Compliance with ASTM B535-06(2022) ensures that seamless pipe and tube products meet international expectations for heat-resistant alloys, making them suitable for critical applications in corrosion resistance and high-temperature service.