Hastelloy B-3 Weld Neck Flanges are forged nickel-molybdenum alloy (improved thermal stability) flanges made from UNS N10675 / W.Nr. 2.4600 material, typically supplied to ASTM B564 material requirements and ASME B16.5 dimensional standards in pressure classes 150# – 2500#. Ragnar Metals & Tubes manufactures and exports these flanges with RF / FF / RTJ facing options, EN 10204 3.1/3.2 documentation, and third-party inspection on request.
Ragnar Metals & Tubes is a B-3 Weld Neck Flange Supplier and manufacturer of Hastelloy B-3 (UNS N10675) weld neck flanges to ASTM B564 and applicable ASME flange dimensional standards, with common sizes and classes available from stock, subject to current inventory, for export and EPC orders.
A weld neck flange carries a machined bore, a sealing face, and a long tapered hub that is butt-welded directly to the mating pipe, giving a full-penetration, high-integrity joint. The tapered hub provides a gradual transition between the pipe and flange, helping reduce stress concentration and making the design suitable for demanding, high-pressure or high-temperature piping applications.
Hastelloy B-3 is a nickel-molybdenum alloy (improved thermal stability) (UNS N10675) known for the same excellent hydrochloric-acid resistance as B-2 with improved thermal stability and fabricability.
UNS Number
Grade
Flange Type
Standard
MTC
Inspection
Origin
Export
| NPS | Outside Diameter | Bolt Circle | No. of Bolts | Bolt Diameter | Flange Thickness |
|---|---|---|---|---|---|
| 1/2" | 3.50" | 2.38" | 4 | 1/2" | 0.38" |
| 3/4" | 3.88" | 2.75" | 4 | 1/2" | 0.44" |
| 1" | 4.25" | 3.12" | 4 | 1/2" | 0.50" |
| 1 1/4" | 4.62" | 3.50" | 4 | 1/2" | 0.56" |
| 1 1/2" | 5.00" | 3.88" | 4 | 1/2" | 0.62" |
| 2" | 6.00" | 4.75" | 4 | 5/8" | 0.69" |
| 3" | 7.50" | 6.00" | 4 | 5/8" | 0.88" |
| 4" | 9.00" | 7.50" | 8 | 5/8" | 0.88" |
| 6" | 11.00" | 9.50" | 8 | 3/4" | 0.94" |
| 12" | 19.00" | 17.00" | 12 | 7/8" | 1.19" |
Reference values for Class 150 only, per ASME B16.5 (source: engineeringtoolbox.com / wermac.org). Verify against the current B16.5 edition before quoting or manufacturing — other classes have different dimensions.
| Class | Standard | Typical Facing |
|---|---|---|
| 150 | ASME B16.5 | RF / FF / RTJ |
| 300 | ASME B16.5 | RF / FF / RTJ |
| 600 | ASME B16.5 | RF / RTJ |
| 900 | ASME B16.5 | RF / RTJ |
| 1500 | ASME B16.5 | RF / RTJ |
| 2500 | ASME B16.5 | RF / RTJ |
Not every class/size combination applies to every flange type. Pressure-temperature ratings must be selected against the applicable ASME rating tables and actual design conditions.
Send us your size, class and quantity — we'll come back with pricing and lead time.
The Middle East and Indian sub-continent are home to hundreds of metal suppliers ranging from small trading shops to large ISO-certified manufacturers. International buyers typically evaluate a supplier on quality compliance, production capability, export experience and pricing transparency before placing a bulk order.
Full-penetration butt weld to the pipe
Tapered hub for smooth stress transfer
Highest-integrity flange style in the ASME B16.5 family
Suited to cyclic loading and thermal expansion
Available in all standard pressure classes
Manufactured from Hastelloy B-3 (UNS N10675) for the same excellent hydrochloric-acid resistance as B-2 with improved thermal stability and fabricability
| Product | Composition | Usage | Standards |
|---|---|---|---|
| Hastelloy B-3 Weld Neck Flange – Standard Class | UNS N10675 | General process piping | ASME B16.5 |
| Hastelloy B-3 Weld Neck Flange – High Pressure | UNS N10675 | High-pressure / critical service | ASME B16.5 |
| Specification | Details |
|---|---|
| UNS Number | N10675 |
| Grade | B-3 |
| Flange Type | Weld Neck Flange |
| Standard | ASTM B564 / ASME B16.5 |
| Werkstoff Number | 2.4600 |
| Pressure Class | 150# – 2500# |
| Facing | RF / FF / RTJ |
| Size (mm) | Size (mm) |
|---|---|
| 15 | 20 |
| 25 | 32 |
| 40 | 50 |
| 65 | 80 |
| 100 | 125 |
| 150 | 200 |
| 250 | 300 |
| 350 | 400 |
| 450 | 500 |
| 600 |
| Element | Composition (%) |
|---|---|
| Nickel (Ni) | Balance |
| Molybdenum (Mo) | 26.0 – 30.0 |
| Chromium (Cr) | 1.0 – 3.0 |
| Iron (Fe) | 1.5 Max |
| Cobalt (Co) | 3.0 Max |
| Carbon (C) | 0.010 Max |
| Property | Value |
|---|---|
| Tensile Strength | 760 MPa Min (annealed) |
| Yield Strength (0.2%) | 350 MPa Min |
| Elongation | 40% Min |
| Property | Metric | Imperial |
|---|---|---|
| Density | 9.22 g/cm³ | 0.333 lb/in³ |
| Melting Point | 1330 – 1380 °C | 2425 – 2515 °F |
| Value (µΩ·m) | Temperature (°C) | Condition |
|---|---|---|
| 1.34 | 20 | Annealed |
| Standard | Werkstoff Nr. | UNS |
|---|---|---|
| UNS | 2.4600 | N10675 |
| ASTM / ASME | B564 / SB564 | N10675 |
| Common Trade Name | Hastelloy B-3 | N10675 |
Forged Hastelloy B-3 billets are pressed into flange blanks, solution annealing to restore corrosion resistance and mechanical properties, then CNC-machined to the required class, bore and facing.
| Process | Temperature | Medium | Purpose |
|---|---|---|---|
| Solution Annealing | 1065 – 1120°C | Rapid Water or Air Quench | Retain corrosion resistance and ductility |
Not sure of every specification? Send your drawing, BOQ or existing part photo and our team can review the requirement.
1/2" – 24" NB · Forged, RF facing
General process piping
1/2" – 12" NB · Forged, RTJ facing
Refinery, high-pressure service
Hydrochloric acid production and handling
Sulfuric acid service
Chemical processing under strongly reducing conditions
Pharmaceutical manufacturing
High-pressure and high-temperature process piping
Critical pipeline connections requiring full weld integrity
| Property | Hastelloy B-3 | Hastelloy B-2 |
|---|---|---|
| Alloy Family | Nickel-Molybdenum Alloy (Improved Thermal Stability) | Nickel-Molybdenum Alloy |
| UNS / Werkstoff | N10675 / 2.4600 | N10665 / 2.4617 |
B-3 improves on B-2's thermal stability and weld-heat-affected-zone toughness while providing the same core HCl resistance.
| Size | Price (USD) | Price (INR) |
|---|---|---|
| 1/2" – 2" NB, 150# | $70 – $160 / pc | ₹5,800 – ₹13,300 / pc |
| 4" – 8" NB, 300# | $300 – $950 / pc | ₹24,900 – ₹78,850 / pc |
| 10" – 24" NB, 600# | $1,400 – $6,000 / pc | ₹1,16,000 – ₹4,98,000 / pc |
Indicative only — actual price depends on size, class, quantity and market rates. Request current pricing above.
Common sizes and standard pressure classes may be available from stock, subject to current inventory. Non-standard sizes, higher pressure classes and project-specific inspection requirements are manufactured or sourced against confirmed orders. Contact us for current stock status and lead time.
MOQ: 25 – 100 Kg / pieces depending on grade, size and product form.
Payment: T/T (bank transfer), Letter of Credit (LC at sight or usance), and SWIFT transfer, depending on order value and buyer requirements.
All export orders are packed in seaworthy, fumigated wooden crates with waterproof inner lining, or palletised packing with clear shipping marks and heat-number identification for full traceability.
Container stuffing is supervised and loading photographs are shared on request, along with certificates of origin, mill test certificates and packing lists for smooth customs clearance at destination ports.
Every Hastelloy B-3 Weld Neck Flange is checked for chemistry, tensile strength, hardness and dimensions before dispatch. PMI, radiography and third-party inspection (TUV, BV, SGS, Lloyd's) are available on request, with EN 10204 3.1/3.2 certification.
Documents listed are available on request; not every document applies to every order.
NPS / DN size
Pressure class
Quantity
Facing
Pipe schedule / bore
Material / standard requirement
MTC requirement
Third-party inspection requirement
Delivery location
Required delivery date
Don't know all the specifications? Send your drawing, BOQ or existing part photo and our team can review the requirement.
B-3 Weld Neck Flange Manufacturer — full mill traceability with every order
B-3 Weld Neck Flange Exporter — export documentation and seaworthy packing for every shipment
B-3 Weld Neck Flange Stockist — common classes and sizes available from stock, subject to inventory
B-3 Weld Neck Flange Distributor — dedicated support for EPC contractors and trading partners
20+ years exporting nickel and specialty alloy flanges
ISO certified quality systems
Hastelloy B-3 sourced and tested to ASTM B564
Mumbai, Delhi, Pune, Chennai, Hyderabad, Bengaluru, Ahmedabad, Rajkot, Coimbatore, Kolkata, Surat, Vadodara
For buyers searching for a B-3 Weld Neck Flange in UAE, Ragnar Metals & Tubes is an India-based manufacturer and exporter supplying Hastelloy B-3 Weld Neck Flanges to buyers and EPC contractors in the UAE, Saudi Arabia, Qatar, Oman, Kuwait and Bahrain, with export documentation and seaworthy packing for every shipment.
UAE, Saudi Arabia, Qatar, Oman, Kuwait, Bahrain, USA, UK, Germany, South Africa, Australia, Malaysia
ISO 9001:2015
ISO 10002:2018
GST Registration
Udyam Registration
Before placing an order, confirm:
Don't know the exact specification yet? Send your BOQ or drawing and we'll confirm it with you.
Send us your size, class and quantity — we'll come back with pricing and lead time.
Browse: All Flanges
A weld neck flange carries a machined bore, a sealing face, and a long tapered hub that is butt-welded directly to the mating pipe, giving a full-penetration, high-integrity joint.
150# – 2500# per ASME B16.5, depending on size and facing.
Yes, EN 10204 3.1 as standard; 3.2 third-party certification on request.
RF / FF / RTJ.
Yes, we regularly export to the UAE, Saudi Arabia, Qatar, Oman, Kuwait and Bahrain.
Yes, through TUV, BV, SGS or Lloyd's before dispatch.
The material is supplied to ASTM B564 (UNS N10675); dimensions follow the applicable ASME flange dimensional standard, including ASME B16.5 and, for larger sizes, ASME B16.47.
Size (NPS/DN), pressure class, facing, quantity, MTC and inspection requirements, and delivery location.
Yes, a sample Material Test Certificate can be shared on request to confirm our documentation format.
The full-penetration weld and tapered hub give better fatigue and stress performance under cyclic loading or high pressure/temperature than a slip-on design.
Hastelloy B-3 offers the same excellent hydrochloric-acid resistance as B-2 with improved thermal stability and fabricability.
Yes — Hastelloy B-3 Weld Neck Flanges in UNS N10675 are exactly what we manufacture and export; share your size, class and quantity and we'll quote directly.
