Seamless Incoloy 800H Tube

Seamless Incoloy 800H Tube (UNS N08810): High-Temperature Creep and Rupture Resistant Alloy Tubing

What Is a Seamless Incoloy 800H Tube?

ASeamless Incoloy 800H Tube (UNS N08810 / W.Nr. 1.4958) is a high-temperature nickel-iron-chromium alloy tube designed for applications requiring exceptional creep resistance, oxidation resistance, and long-term structural stability at elevated temperatures.

Manufactured from a solid alloy billet through a seamless process, Incoloy 800H tubes contain no longitudinal weld seam. This manufacturing method provides a uniform grain structure, improved mechanical strength, and higher reliability in high-pressure and high-temperature industrial environments.

Incoloy 800H is the high-carbon modification of the standard Incoloy 800 alloy. The controlled carbon content (0.05–0.10%) combined with high-temperature solution annealing improves grain stability and significantly enhances creep-rupture strength above 600°C (1112°F).

Because of these properties, seamless Incoloy 800H tubes are widely used in petrochemical, power generation, furnace, and chemical processing systems operating under extreme heat conditions.

Key Advantages of Seamless Incoloy 800H Tubes

Superior Creep and Rupture Strength

The controlled carbon content and optimized grain structure of Incoloy 800H provide exceptional resistance to creep deformation during prolonged exposure to high temperatures and stress.

This makes the alloy suitable for long-term service in high-temperature industrial equipment.

Excellent Oxidation and Carburization Resistance

The alloy's high chromium and nickel content forms a stable protective oxide layer on the surface. This oxide scale helps protect the material from:

• Oxidizing atmospheres
• Carburizing environments
• Nitriding conditions
• High-temperature corrosion

These properties allow Incoloy 800H tubes to perform reliably in extreme thermal environments.

Seamless Structural Integrity

Compared with welded tubing, seamless Incoloy 800H tubesoffer:

• Higher pressure resistance
• Uniform metallurgical structure
• Improved mechanical reliability
• Reduced risk of weld-related failure

The absence of a weld seam eliminates potential weak points in high-temperature applications.

Excellent High-Temperature Performance

Incoloy 800H tubes are capable of continuous service at temperatures approaching 1100°C (2012°F) while maintaining stable mechanical properties and structural integrity.

Product Specifications and Data

To provide a comprehensive overview of this high-performance material, here are the detailed technical specifications and performance data for Incoloy 800H.

Table 1: Chemical Composition of Incoloy 800H Under ASTM B407

The enhanced strength of Incoloy 800H is a direct result of its controlled carbon content, while retaining the essential nickel and chromium levels for heat and corrosion resistance.

Table 2: Typical Mechanical Properties of Incoloy 800H Under ASTM B407 

Incoloy 800H is specifically designed to maintain its strength and shape in high-stress, high-temperature applications.

Table 3: Typical Physical Properties of Incoloy 800H Under ASTM B407 

These physical properties highlight the material's ability to perform reliably under extreme thermal conditions.

Table 4: The Standard of Seamless Incoloy 800HT Pipe ASTM B407 Size Tolerance Chart :

Cold-Finished Pipes and Tubes:

Industrial Applications of Seamless Incoloy 800H Tubes

Due to its outstanding thermal stability and corrosion resistance, Incoloy 800H seamless tubing is widely used in industries requiring reliable materials for extreme temperature environments.

Petrochemical Processing

In petrochemical plants, Incoloy 800H tubes are commonly used for:

• Ethylene cracking furnace tubes
• Pigtails and transfer lines
• High-temperature headers
• Process gas heaters

These systems operate under intense heat and chemical exposure.

Power Generation

Power plants require materials that can withstand high temperatures and pressure. Seamless 800H tubes are frequently used in:

• Superheater tubing
• Reheater systems
• Steam generation equipment
• Nuclear power heat systems

Heat Treating and Industrial Furnaces

Incoloy 800H performs exceptionally well in high-temperature furnace environments. Typical components include:

• Furnace retorts
• Radiant tubes
• Mufflers
• Conveyor components

Chemical Processing

The alloy is also used in chemical production equipment, including:

• Nitric acid plants
• Vinyl chloride monomer (VCM) production
• Catalyst support structures

Quality Assurance and Compliance Standards

To meet strict international engineering standards, seamless Incoloy 800H tubes undergo comprehensive quality inspection and documentation procedures.

Certification and Material Traceability

Each shipment is accompanied by full documentation including:

• EN 10204 3.1 / 3.2 Material Test Certificates (MTC)
• Raw material origin certificates
• Heat treatment records and charts
• Third-party inspection reports from organizations such as SGS, BV, or TÜV

These documents ensure complete traceability and compliance with global industrial standards.

Testing and Inspection Procedures

To guarantee product reliability and performance, tubes undergo rigorous testing including:

Non-Destructive Testing (NDT)

• Positive Material Identification (PMI)
• Eddy Current Testing (ET)
• Ultrasonic Testing (UT)

Mechanical Testing

• Tensile strength testing
• Hardness testing
• Impact testing
• Flattening and flare testing

Metallurgical Testing

• Grain size analysis (critical for 800H performance)
• Intergranular corrosion (IGC) testing

Dimensional Inspection

• Outer diameter and wall thickness measurement
• Straightness and surface finish inspection

Why Choose Seamless Incoloy 800H Tubes Instead of Welded Tubes?

In high-temperature industrial environments, the weld zone of a tube is often the most vulnerable area for creep failure, oxidation, or stress rupture.

By choosing seamless Incoloy 800H tubes, these potential weaknesses are eliminated.

Key advantages include:

1. Uniform creep resistance throughout the entire tube wall
2. Higher safety margins for high-pressure steam or gas systems
3. Improved resistance to thermal fatigue
4. Longer service life in corrosive high-temperature environments
5. Reduced maintenance costs and downtime

These benefits make seamless 800H tubing the preferred choice for critical high-temperature applications.

Conclusion

Seamless Incoloy 800H Tubes (UNS N08810) are high-performance nickel-iron-chromium alloy tubes engineered for extreme temperature environments requiring exceptional creep resistance, oxidation resistance, and long-term structural stability.

With their seamless construction, controlled alloy chemistry, and superior high-temperature strength, Incoloy 800H tubes are widely used in petrochemical plants, power generation systems, industrial furnaces, and chemical processing equipment.

For industries operating under severe heat and pressure conditions, seamless Incoloy 800H tubing provides a reliable and durable material solution.

FAQ

What is Incoloy 800H used for?
Incoloy 800H is primarily used in high-temperature industrial environments such as petrochemical processing, power generation, and furnace equipment.

What is the difference between Incoloy 800 and 800H?
Incoloy 800H has a higher controlled carbon content and optimized grain size, which improves creep and rupture strength at elevated temperatures.

Why are seamless Incoloy 800H tubes preferred for high-temperature service?
Seamless tubes eliminate weld seams, reducing the risk of structural failure and providing more uniform mechanical properties in high-temperature conditions.