ASTM B423 is the standard specification for seamless hot-finished and cold-worked nickel-iron-chromium-molybdenum-copper alloy pipe and tube, covering UNS N08825 (Incoloy 825), UNS N08221 and UNS N06845 grades, with general manufacturing requirements complying with ASTM B829ASTM International.
These seamless nickel alloy tubes are formulated with nickel, chromium, molybdenum and copper, delivering outstanding resistance to oxidizing/reducing acids, seawater, pitting, crevice corrosion and chloride-induced stress corrosion cracking, alongside stable mechanical strength under high temperature and pressure. The standard regulates strict chemical composition, tensile/yield strength, dimensional tolerance, hydrostatic test and non-destructive inspection to guarantee leak-tight and reliable performance in severe corrosive service.
Core Applications
- Chemical & petrochemical industry: Heat exchangers, evaporators and process piping for sulfuric, phosphoric and mixed acid production lines.
- Oil & gas sector: Downhole tubing and pipeline components for sour wells with H₂S and CO₂ corrosion.
- Power & environmental protection: Flue gas desulfurization (FGD) scrubber tubes and auxiliary cooling circuits in thermal power plants.
- Marine & desalination: Seawater heat exchangers and offshore platform fluid piping resisting saltwater erosion.
- Nuclear industry: Corrosion-resistant tubing for fuel reprocessing and auxiliary cooling systems.
