ASTM A407 N08810 Heat Exchanger Tube Chemical Composition

ASTM B407 N08810 Heat Exchanger Tube Application

Tubes are used in extreme environments:

1. Petrochemical: Ethylene furnace coils, reformer tubes, pyrolysis units.
2. Power Generation: Superheater tubes, heat exchangers, boiler components.
3. Nuclear: Steam generator tubing, heat exchangers (resists chloride stress corrosion).
4. Industrial Furnaces: Radiant tubes, muffles, conveyor systems.
5. Chemical Processing: Acid production, catalyst support grids.

ASTM B407 N08810 Heat Exchanger Tube Strength & Mechanical Properties

• Room Temperature:

Tensile Strength: ≥500 MPa (72.5 ksi)

Yield Strength (0.2% offset): ≥170 MPa (25 ksi)

Elongation: ≥30%

• Elevated Temperature (650°C / 1200°F):

Tensile Strength: ~380 MPa (55 ksi)

Creep Rupture Strength: Excellent (e.g., 10,000 hrs at 815°C: ~20 MPa)

• Key Strengths: Retains structural integrity under thermal cycling/stress; superior to standard stainless steels (e.g., 304/316) above 600°C.
• High-Temperature Performance: Outperforms stainless steels in creep strength above 600°C.
• Corrosion Resistance: Resists oxidation, carburization, and reducing sulfur atmospheres.
• Fabricability: Weldable (using ENiCrFe-3 filler) and formable with standard methods.
• Cost-Effective: More economical than high-nickel alloys (e.g., Inconel) for moderate temperatures.

ASTM B407 N08810 Heat Exchanger Tube FAQ

1. What distinguishes Incoloy 800H from standard Incoloy 800?

800H has a higher carbon content (0.05–0.10% vs. 0.03% max in 800) for superior creep resistance at >600°C.

It undergoes solution annealing at ≥1100°C to achieve an ASTM No. 5 or coarser grain size, optimizing high-temperature strength.

2. What temperatures can Incoloy 800H tubes handle?

Continuous Service: Up to 815°C (1500°F).

Short-Term Exposure: Up to 950°C (1740°F).

Critical Note: For >900°C, Incoloy 800HT (Ti/Al-controlled) is preferred for enhanced stability.

3. Is welding 800H tubes difficult?

Weldable via:

TIG/GTAW with ERNiCr-3 (FM 82) filler.

SMAW with ENiCrFe-3 electrodes.

Post-Weld Requirement: Solution annealing (1100–1175°C) is essential to restore corrosion/creep resistance.