Hastelloy C276 Tube for Heat Exchanger Applications

Heat exchangers in chemical and industrial plants operate under high temperatures, corrosive chemicals, and pressure cycling. Hastelloy C276 (UNS N10276) is a nickel-chromium-molybdenum-cobalt alloy engineered for such harsh conditions. Seamless C276 tubes ensure uniform corrosion resistance, high mechanical strength, and reliability, reducing downtime and maintenance in critical industrial processes. 

Why Hastelloy C276 is Ideal for Heat Exchangers

Corrosion Resistance

Hastelloy C276 offers excellent protection in a wide range of corrosive fluids:

Environment	Performance
Sulfuric Acid	Excellent
Hydrochloric Acid	Excellent
Nitric Acid	Very Good
Phosphoric Acid	Excellent
Chloride Solutions	Excellent
Mixed Acid Systems	Excellent

This is due to its carefully balanced Ni-Cr-Mo-Co composition, forming a passive layer that resists pitting, crevice corrosion, and stress corrosion cracking.

Mechanical Strength and Thermal Stability

Hastelloy C276 maintains structural integrity under high temperature and pressure.

Property	Value
Tensile Strength	≥485 MPa
Yield Strength	≥205 MPa
Elongation	≥30%
Hardness	≤95 HRB
Operating Temperature	Up to 200°C

These properties are essential for heat exchanger tubes exposed to thermal cycling and mechanical stress.

Heat Exchanger Applications

Shell-and-Tube Heat Exchangers

C276 tubes are ideal for shell-and-tube units handling oxidizing acids and chloride-rich streams.

Evaporators and Condensers

Used in acid concentration and heat recovery processes, C276 tubes maintain durability and performance.

Cooling Coils and Process Piping

They ensure long service life in corrosive media and high-temperature environments.

Advantages over Stainless Steel

Feature	C276 Tube	316L Stainless Steel
Corrosion Resistance	Excellent	Fair
Pitting/Crevice Resistance	Excellent	Poor
Oxidizing Acid Resistance	Excellent	Moderate
Reducing Acid Resistance	Excellent	Good
Lifecycle Cost	Lower (long-term)	Higher (short-term)

C276 is preferred where reliability, corrosion resistance, and longevity are critical.

Tube Sizes and Specifications

Parameter	Range
Outside Diameter	6 mm – 114.3 mm
Wall Thickness	0.5 mm – 10 mm
Length	Up to 12 meters
Tube Type	Seamless
Surface Finish	Pickled, Bright Annealed, Polished

Custom dimensions are available for specific heat exchanger designs.

Quality Assurance and Testing

C276 tubes undergo rigorous testing:

PMI testing for chemical composition

Hydrostatic testing for pressure integrity

Eddy current and ultrasonic testing for defects

Mechanical tests: tensile, flattening, and hardness

Dimensional inspection

All tests comply with ASTM B622 and EN 10204 3.1 standards.

FAQ

Q1: Can C276 tubes replace stainless steel in heat exchangers?
A1: Yes, especially in aggressive acid environments where 316L fails.

Q2: Are seamless or welded tubes preferred?
A2: Seamless tubes offer uniform corrosion resistance and higher pressure rating.

Q3: What acids can C276 handle?
A3: Sulfuric, hydrochloric, nitric, phosphoric acids, and mixed acid streams.

Q4: What certifications should be requested?
A4: ASTM B622, UNS N10276, EN 10204 3.1, PMI, hydrostatic test certificates.

Q5: Can C276 tubes be customized?
A5: Yes, TSM Technology provides custom diameters, wall thicknesses, and lengths.

Conclusion

Hastelloy C276 tubes provide excellent corrosion resistance, mechanical strength, and thermal stability for heat exchangers in chemical and industrial plants. Selecting certified C276 tubes ensures long-term performance, safety, and reliability.

Email: info@tsm-titanium.com