High-temperature seamless pipes must withstand thermal expansion, oxidation, and creep deformation over extended periods.

Key Materials for High-Temperature Seamless Pipes:

A335 P91 (Modified 9Cr-1Mo Steel): High creep resistance, used in boiler tubes.
Inconel 625: Superior oxidation resistance, applied in gas turbine exhaust systems.
Hastelloy C-276: Handles extreme acidic environments in high temperatures.

Challenges of High-Temperature Service:

Carburization: Carbon diffusion can lead to brittle pipe structures.
Thermal Fatigue: Repeated heating/cooling cycles cause microcracking.
Grain Growth: At extreme temperatures, microstructure coarsening reduces strength.

Applications:

Superheater tubes in power plants.
Catalytic reforming reactors in petrochemical industries.