ASTM B676-19(2024) PDF

Overview

ASTM B676-19(2024) is an international standard specification developed by ASTM International for UNS N08367 welded tube, catering to general corrosion applications. This specification covers tubes produced from flat-rolled alloy, manufactured via automatic welding without added filler metal. The finished product is delivered with oxide removed, ensuring optimal integrity and surface finish. ASTM B676 defines requirements for tube diameter, wall thickness, mechanical properties, chemical composition, testing, and certification, promoting quality and consistency across applications in corrosive service environments.

Key Topics

• Product Scope: Defines welded tube sizes from 1/8 inch to 5 inches (3.2 mm to 127 mm) in outside diameter and 0.015 inch to 0.320 inch (0.38 mm to 8.13 mm) in wall thickness.
• Material Composition: Specifies alloying elements such as carbon, manganese, silicon, phosphorus, sulfur, chromium, nickel, molybdenum, nitrogen, iron (balance), and copper.
• Manufacturing Process:
  • Tubes are made from flat-rolled alloy using an automatic welding process without filler metal.
  • Cold working is applied after welding and before solution treatment.
  • Tubes are supplied with oxide removed for improved performance in corrosive environments.
• Testing Requirements:
  • Mandatory mechanical tests include tensile, flattening, flange, and reverse-bend tests (with some size-based exceptions).
  • Nondestructive tests or pressure tests (hydrostatic, pneumatic, eddy current, or ultrasonic) are required for each tube.
  • Test results must show no evidence of cracking, flaws, or weld deficiencies.
• Dimensional Standards: Adopts inch-pound units as standard, with SI conversions provided for information.
• Certification: Requires manufacturers to provide certification confirming that tubes comply with all specified requirements, accompanied by representative test results.

Applications

UNS N08367 welded tube, as standardized in ASTM B676, offers significant value for a wide range of general corrosion applications, especially in environments demanding resistance to aggressive media. Typical applications include:

• Chemical processing plants, where exposure to chlorides and acids is routine.
• Petrochemical and oil & gas industries, for heat exchangers, condenser tubes, and piping exposed to corrosive substances.
• Power generation environments, including cooling systems and condensers.
• Desalination plants and marine applications, where enhanced resistance to seawater and brine is critical.
• Pharmaceutical and food industries, leveraging the alloy’s cleanliness and corrosion resistance for sanitary tube systems.

ASTM B676 ensures that users obtain high-performance welded tube products that consistently meet chemical, mechanical, and dimensional standards, supporting long service life and safety in demanding operating conditions.

Related Standards

The following standards are frequently referenced or associated with ASTM B676-19(2024):

• ASTM B751 - General Requirements for Nickel and Nickel Alloy Welded Tube: Specifies broader quality and testing requirements applicable to welded tubes, including those made from UNS N08367.
• ASTM B899 - Terminology Relating to Non-ferrous Metals and Alloys: Provides essential definitions to ensure clarity in specifying and interpreting alloy tube standards.
• ASTM A1016/A1016M - General Requirements for Ferritic, Austenitic Alloy Steel, and Stainless Steel Tubes: Covers the common testing, inspection, and reporting procedures for tube manufacturing.

By adhering to ASTM B676 and its related standards, manufacturers, engineers, and end-users ensure reliable performance, optimal material selection, and regulatory compliance in corrosion-resistant tube applications.

Keywords: ASTM B676, UNS N08367, welded tube, corrosion resistance, nickel alloy tube, ASTM tube standard, alloy tube specification, mechanical testing, pressure testing, oxide free tube, industrial applications.