Hastelloy B-3 Spectacle Blinds 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# – 1500#. Ragnar Metals & Tubes manufactures and exports these flanges with RF / FF facing options, EN 10204 3.1/3.2 documentation, and third-party inspection on request.
Ragnar Metals & Tubes is a B-3 Spectacle Blind Supplier and manufacturer of Hastelloy B-3 (UNS N10675) spectacle blinds 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 spectacle blind is a figure-8 shaped plate combining a solid blind disc and an open ring spacer, connected by a web, allowing a line to be switched between fully open and fully closed without removing the plate from the bolt circle. To change state, the line is depressurized, the bolts loosened, and the plate rotated so the open ring or the solid blind sits in the flow path — a faster, safer alternative to swapping loose blinds and spacers for planned isolation.
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
| 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.
Combined blind disc and spacer ring in one figure-8 plate
Rotates between open and closed states without full bolt removal
Clear visual indication of line status
Used for planned, positive line isolation
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 Spectacle Blind – Standard Class | UNS N10675 | General process piping | ASME B16.5 |
| Hastelloy B-3 Spectacle Blind – High Pressure | UNS N10675 | High-pressure / critical service | ASME B16.5 |
| Specification | Details |
|---|---|
| UNS Number | N10675 |
| Grade | B-3 |
| Flange Type | Spectacle Blind |
| Standard | ASTM B564 / ASME B16.5 |
| Werkstoff Number | 2.4600 |
| Pressure Class | 150# – 1500# |
| Facing | RF / FF |
| 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 plate, RF/FF facing
Positive line isolation
Hydrochloric acid production and handling
Sulfuric acid service
Chemical processing under strongly reducing conditions
Pharmaceutical manufacturing
Positive isolation of piping sections for maintenance or safety
Turnaround and shutdown isolation points
| 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 Spectacle Blind 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 Spectacle Blind Manufacturer — full mill traceability with every order
B-3 Spectacle Blind Exporter — export documentation and seaworthy packing for every shipment
B-3 Spectacle Blind Stockist — common classes and sizes available from stock, subject to inventory
B-3 Spectacle Blind 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 Spectacle Blind in UAE, Ragnar Metals & Tubes is an India-based manufacturer and exporter supplying Hastelloy B-3 Spectacle Blinds 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 spectacle blind is a figure-8 shaped plate combining a solid blind disc and an open ring spacer, connected by a web, allowing a line to be switched between fully open and fully closed without removing the plate from the bolt circle.
150# – 1500# 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.
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 blind and spacer are joined in one plate, so the line status is always visually obvious and the components can't be misplaced or installed incorrectly.
Hastelloy B-3 offers the same excellent hydrochloric-acid resistance as B-2 with improved thermal stability and fabricability.
Yes — Hastelloy B-3 Spectacle Blinds in UNS N10675 are exactly what we manufacture and export; share your size, class and quantity and we'll quote directly.
