UNS N10665|2.4617|Hastelloy B2 Seamless Tube
Thanks to their excellent corrosion resistance, high mechanical strength, and thermal stability, Hastelloy B2 seamless tubes perform reliably under high temperature and high-pressure operating conditions.
XINZHE, a professional nickel alloy tube manufacturer and supplier based in Wenzhou, China, specializes in producing precision seamless Hastelloy B2 tubes in compliance with international standards such as ASTM B622 / ASME SB622. Our products are manufactured using advanced production technology and strict quality control procedures.
Each tube undergoes comprehensive inspection and testing, including:
Chemical composition analysis
Mechanical property testing
Non-destructive testing (NDT)
Hydrostatic or eddy current testing
Full material traceability documentation
All tubes are carefully packaged and fully prepared for global export, ensuring consistent quality, reliable performance, and long service life in demanding industrial environments.
What Is a Seamless Hastelloy B2 Tube?
Hastelloy B2 (UNS N10665) is a nickel-molybdenum alloy with outstanding resistance to hydrochloric acid, sulphuric acid and other strongly reducing media. Its very low chromium content keeps it free of the passive-film behaviour that makes high-chromium alloys vulnerable to chloride attack, so B2 is the reference material for handling hot concentrated HCl and contaminated sulphuric acid.
Key Features and Technical Advantages
Outstanding Resistance to Hydrochloric Acid
Hastelloy B2 is the reference alloy for hot hydrochloric acid and other strongly reducing media, across wide concentration ranges.
Resistance to Sulphuric Acid
The alloy handles sulphuric acid and contaminated sulphuric acid where high-chromium grades would suffer rapid attack.
Freedom from Chloride Pitting
Its very low chromium content removes the susceptibility to chloride-induced pitting that limits high-chromium alloys in reducing service.
High-Temperature Corrosion Resistance
B2 resists corrosion in hydrochloric acid at elevated temperature, the duty that defines the practical limit of most alloys.
Good Fabricability
The alloy is readily formed and welded, with matching filler available for corrosion-critical joints.
Product Specifications and Data
To provide a comprehensive overview of this high-performance material, here are the detailed technical specifications and performance data for Hastelloy B2.
The composition of Hastelloy B2 is carefully balanced to achieve its superior corrosion resistance and high strength.
| Grade | Ni | Cr | Mo | Fe | C | Si | Co | Mn | P | S |
| UNS N10665 | Balance | ≤1.00 | 26.00-30.00 | ≤2.00 | ≤0.02 | ≤0.10 | ≤1.00 | ≤1.00 | 0.04 | 0.03 |
Hastelloy B2 is specifically designed to maintain its strength and shape in high-stress, corrosive environments.
Tensile Strength | Yield Strength | Elongation | Hardness |
≥ 760 MPa | ≥ 350 MPa | ≥ 40% | ≤ 100 HRB |
Strategic Industrial Applications
The combination of high mechanical strength and extreme chemical resistance makes Seamless B2 tubes the preferred choice for:
- Chemical & Petrochemical Processing: Reactors, heat exchangers, and piping systems handling aggressive reducing acids.
- Pharmaceutical Production: Critical equipment involving highly reactive reducing agents and high-purity requirements.
- Waste Management: Handling systems for hazardous, corrosive waste streams and acidic by-products.
- Specialized Acid Production: Essential for acetic acid (vinegar) production and other organic acid processing plants.
Dimensional Standards and Tolerances
Hastelloy B2 seamless tubes are supplied to the dimensional tolerances of ASTM B622 / B829 unless a tighter project specification applies.
Common Industrial Applications
Chemical Processing
- Hydrochloric acid service equipment
- Reactors, heat exchangers and vessels
- Sulphuric acid handling
Petrochemical Processing
- Acetic acid and PTA plants
- Vacuum and distillation equipment
- Process piping
Pharmaceutical and Fine Chemicals
- Reactor vessels and internals
- Corrosive media transfer lines
- Purification equipment
Pollution Control
- Waste-acid recovery systems
- Scrubber internals
- Effluent handling equipment
Quality Assurance and Manufacturing Process
Certification
All Hastelloy B2 tubes are supplied to ASTM B622 / ASME SB622 and ASTM B619 / ASME SB619 with EN 10204 3.1 mill test certificates. Third-party inspection (SGS, BV, TUV, Lloyd's), PMI reports and full heat-number traceability can be provided on request.
Non-Destructive Testing (NDT)
Hydrostatic or eddy-current testing is performed on 100% of tubes. Ultrasonic testing (UT) and dye-penetrant inspection (PT) are available for critical service, with records retained for each production lot.
Material Verification
Positive Material Identification (PMI) and spectrometric analysis confirm that the chemical composition matches the ordered grade. Intergranular corrosion (IGC) testing to ASTM A262 Practice E is available for austenitic and nickel-alloy tubes.
Mechanical Testing
Tensile, yield, elongation and hardness tests are carried out per heat. Flattening, flaring and reverse-bend tests verify ductility, while creep-rupture data can be supplied for high-temperature grades.
Dimensional Inspection
Outside diameter, wall thickness, ovality and straightness are measured against ASTM A1016 / A1016M or EN 10216-5 tolerances. Length, square-cut ends and end-finish conditions are verified before packing.
Hastelloy B2 vs Hastelloy B3 / C276 – Technical Comparison
Hastelloy B2 is the classic nickel-molybdenum alloy for reducing acids. B3 and C276 are the two directions the family evolved in.
Chemistry
- B2: nickel-molybdenum with very low chromium and iron
- B3: nickel-molybdenum with tightly controlled iron and chromium for better phase stability
- C276: nickel-molybdenum-chromium with tungsten — an oxidising-media capability B2 does not have
Reducing-Acid Performance
B2 remains the reference material for hot hydrochloric acid and contaminated sulphuric acid. Both B3 and C276 perform well in the same media, but B2 does so with the simplest chemistry and the lowest cost.
Oxidising Media and Localised Corrosion
Because it is essentially chromium-free, B2 must not be used where oxidising species are present — they accelerate attack severely. C276 handles mixed oxidising and reducing chemistry and resists chloride pitting, which B2 cannot claim.
Selection Guide
- Choose Hastelloy B2 for pure reducing-acid service at the lowest cost
- Choose Hastelloy B3 where the same service involves welded fabrication or intermediate-temperature exposure
- Choose Hastelloy C276 whenever oxidising species, chlorides or mixed chemistry are present
Frequently Asked Questions
What is a Hastelloy B2 seamless tube?
Hastelloy B2 (UNS N10665) is a nickel-molybdenum alloy tube produced without a longitudinal weld, with outstanding resistance to hydrochloric acid, sulphuric acid and other strongly reducing media. It is essentially free of chromium.
What environments is Hastelloy B2 suitable for?
B2 is the reference material for hot hydrochloric acid across a wide concentration range, for contaminated sulphuric acid, and for other reducing media where high-chromium alloys would suffer rapid attack.
What is the main limitation of Hastelloy B2?
Two limitations matter. It must not be used where oxidising species are present, since they accelerate attack severely. It is also susceptible to intermetallic-phase embrittlement in the 600–1,000 °C range, which restricts welding and intermediate-temperature service — the limitation that Hastelloy B3 was developed to address.
What standard covers Hastelloy B2 tube?
Hastelloy B2 seamless tube is supplied to ASTM B622 / ASME SB622, with ASTM B829 covering general requirements and ASTM B619 / ASME SB619 applying to welded pipe.
Ready to Request a Quotation?
Send your Seamless Hastelloy B2 Tube enquiry with grade, application, size (OD and wall thickness or schedule), quantity, length, end finish and inspection requirements. Our technical team will confirm availability, testing scope and lead time.
