What is Incoloy 800H Welded Tubes and Their Applications
Overview
Incoloy 800H is a nickel‑iron‑chromium alloy from the 800 series designed for reliable performance in high‑temperature, corrosive environments. It combines good fabricability—using standard stainless‑steel equipment and processes—with enhanced resistance to oxidation, sulfidation, and stress‑corrosion cracking when properly specified and heat‑treated.
Composition and material properties
Incoloy 800H is primarily a nickel‑iron‑chromium alloy with controlled additions of molybdenum, copper, and titanium. The chemistry is balanced to deliver:
- High creep and rupture strength at elevated temperatures
- Good oxidation and carburization resistance
- Improved resistance to sulphur‑bearing atmospheres and many industrial corrosives
- Excellent dimensional stability after prolonged high‑temperature exposure
Incoloy versus Inconel
The main distinction between Incoloy and Inconel is composition and typical application focus:
- Inconel alloys are nickel‑rich (often >50% Ni) and emphasize exceptional high‑temperature strength and corrosion resistance.
- Incoloy alloys (including 800H) contain less nickel and more iron, offering a cost‑effective balance of high‑temperature strength and good corrosion performance for less severe environments.
Key features of Incoloy 800H welded tubes
- High temperature capability and excellent creep rupture strength
- Good resistance to sulphur‑containing gases and many industrial corrosives
- Stable mechanical properties after prolonged exposure at elevated temperatures
- Fabricable by standard welding, forming, and finishing methods used for stainless steels
- Available in welded tube form for economical delivery of large diameters and long lengths
Typical applications
Incoloy 800H welded tubes are used where sustained high temperature and moderate corrosive attack coexist, including:
- Heat‑treating equipment (baskets, trays, fixtures)
- Industrial furnace components exposed to 1100–1800 °F (593–982 °C)
- Superheaters and reheaters in power plants
- Heat exchangers and high‑pressure vessels
- Petrochemical and chemical process equipment, including hydrocarbon cracking systems
- Components exposed to nitric acid or chloride‑stress environments where appropriate grade selection is required
- Pulp and paper industry process equipment
Why choose Incoloy 800H welded tubes
- Cost‑effective alternative to higher‑nickel alloys when service demands are moderate to severe but not extreme
- Can be produced and processed using conventional stainless‑steel fabrication equipment
- Well suited to welded tube production for economical long lengths and larger diameters
- Versatile across multiple industries where high‑temperature strength and corrosion resistance are required
Selection and specification tips
- Specify 800H (the “H” grade) for applications requiring improved creep strength at elevated temperatures.
- Confirm service chemistry: for aggressive chloride or sulfuric environments, evaluate alternate alloys or protective measures.
- Ensure proper post‑weld heat treatment and fabrication practice to preserve high‑temperature properties and corrosion resistance.
Choose Incoloy 800H welded tubes when you need a dependable, weldable alloy with strong high‑temperature performance and broad applicability across heat‑treating, power generation, and chemical processing plants.
