1. What materials are covered under ASTM B167 seamless nickel alloy pipes and tubes?
ASTM B167 covers nickel and nickel-based superalloy seamless pipes and tubes, including:
Inconel 600, 625, 617, 718 – for high-temperature strength, oxidation, and corrosion resistance
Incoloy 800, 800H, 800HT – for high-temperature oxidation and moderate corrosion resistance
These alloys are ideal for high-pressure, high-temperature, and chemically aggressive applications.
2. What industries commonly use these superalloy seamless tubes?
Aerospace and defense – engine components, high-temperature tubing
Oil and gas – high-pressure pipelines, offshore applications
3. Why are seamless tubes preferred over welded tubes for these superalloys?
Seamless construction ensures long-term durability and safety in critical applications.
4. What temperature and pressure ranges can these superalloy tubes handle?
Inconel 600/625: up to ~980℃ (1800℃F) continuous service
Inconel 617/718: up to 1000℃ (1830℃F), excellent high-temperature strength
Incoloy 800/800H/800HT: up to 700–850℃ (1290–1560℃F) depending on grade
These tubes can also withstand high-pressure fluids and maintain mechanical integrity under thermal cycling.
5. How do the different alloys compare in corrosion resistance and high-temperature performance?
Inconel 600/625: excellent oxidation and corrosion resistance at high temperatures
Inconel 617/718: higher high-temperature strength, suitable for furnace and aerospace applications
Incoloy 800/800H/800HT: good oxidation resistance, moderate chemical corrosion resistance, optimized for industrial heating and process piping
Selection depends on operating environment, temperature, and chemical exposure.
