1. What is the composition of Inconel 600 and Inconel 800 in ASME SB167?
Answer:
Inconel 600:
Nickel (Ni): 72%
Chromium (Cr): 14-17%
Iron (Fe): Balance
It also contains small amounts of manganese, silicon, carbon, sulfur, and others.
Inconel 800:
Nickel (Ni): 30-35%
Chromium (Cr): 19-23%
Iron (Fe): Balance
It also contains small amounts of carbon, manganese, and aluminum, which enhance its resistance to oxidation and carburization at high temperatures.
2. What are the primary applications of Inconel 600 and Inconel 800 seamless pipes/tubes?
Answer:
Inconel 600: Primarily used in chemical processing, gas turbines, nuclear reactors, and heat exchangers, where high-temperature oxidation and corrosion resistance are crucial.
Inconel 800: Used in applications that require higher temperature strength and resistance to oxidation and carburization, such as furnace components, petrochemical industry, heat exchangers, and gas turbines.
3. What are the mechanical properties of Inconel 600 and Inconel 800 pipes/tubes?
Answer:
Inconel 600:
Tensile Strength: ~515 MPa
Yield Strength: ~170 MPa
Elongation: 35-45%
Hardness (Brinell): ~90 HB
Inconel 800:
Tensile Strength: ~620 MPa
Yield Strength: ~310 MPa
Elongation: 30-40%
Hardness (Brinell): ~150 HB
4. How do these alloys perform at high temperatures?
Answer:
Inconel 600: Performs well in high-temperature environments (up to 1,100°C or 2,010°F), particularly in reducing and neutral atmospheres. It offers excellent oxidation resistance at these temperatures.
Inconel 800: Can withstand even higher temperatures (up to 1,200°C or 2,192°F), offering better resistance to oxidation and carburization, making it ideal for furnace components and petrochemical applications.
5. What are the welding considerations for Inconel 600 and Inconel 800 seamless pipes/tubes?
Answer:
Inconel 600:
Welding can be done with most conventional methods such as TIG, MIG, or Stick welding. Preheating is recommended to avoid cracking. Post-weld heat treatment may be necessary to relieve stresses.
Inconel 800:
Welding is typically done using TIG or MIG methods. Post-weld heat treatment is also recommended to improve material properties and reduce the risk of cracking, especially in high-temperature applications.
These questions and answers cover the basic composition, applications, mechanical properties, high-temperature performance, and welding considerations of ASME SB167 Inconel 600 and Inconel 800 Nickel alloy seamless pipes and tubes.
