Hastelloy C276 Spectacle BlindASTM B462 · ASME B16.48 · Manufacturer, stockist & exporter, India
Alloy C-276 · UNS N10276 · SB
A Hastelloy C276 spectacle blind is a figure-8 plate with one solid end and one open ring, fitted between two flanges, made from Hastelloy C276 to ASTM B462 / B564. A spectacle blind lets operators positively isolate a line: rotate the solid end into the line to block flow, or the ring end to allow it. Larger sizes use separate spacers and paddle blanks.
- ASTM B462
- ASME B16.48
- EN 10204 3.1 / 3.2
- Export packing
Reviewed by the Kanak Steel & Engineering Co. technical team · Updated October 2026
What is a Hastelloy C276 Spectacle Blind?
- What it is
- A figure-8 plate with one solid end and one open ring, fitted between two flanges
- Material
- ASTM B462 / B564
- Dimensions
- ASME B16.48
- Grade
- Hastelloy C276 · UNS N10276
- Best at
- The most aggressive mixed acids, wet chlorine and hypochlorite
Hastelloy C276 Spectacle Blind Specification
| Product | Hastelloy C276 Spectacle Blind |
|---|---|
| Material standard | ASTM B462 / B564 |
| Dimensional standard | ASME B16.48 |
| Sizes | ½" – 24" (ASME B16.5) · 26" – 60" (ASME B16.47) |
| Pressure class | Class 150, 300, 400, 600, 900, 1500, 2500 · PN 6 – PN 100 |
| Facing | RF · FF · RTJ · tongue & groove |
| Bore | To match pipe schedule (state on order) |
| Testing | PMI · dimensional · NDT and IGC on request |
| Documents | EN 10204 3.1 · 3.2 with third-party inspection |
When to Choose a Spectacle Blind
A spectacle blind lets operators positively isolate a line: rotate the solid end into the line to block flow, or the ring end to allow it. Larger sizes use separate spacers and paddle blanks.
- Thickness set by class and size
- Paddle blank and spacer versions for large bores
- Handle or lifting lug to order
More on choosing: Spectacle blind guide.
Hastelloy C276 Spectacle Blind: Why C276 for spectacle blinds
A spectacle blind lets operators positively isolate a line: rotate the solid end into the line to block flow, or the ring end to allow it. Larger sizes use separate spacers and paddle blanks. In Hastelloy C276, the choice usually comes down to the medium and temperature — the rows here are the points buyers check for this exact combination.
| Why this grade | Nickel-alloy flanges are used where acids, chlorides or heat defeat stainless. Hastelloy C276 is picked for the most aggressive mixed acids, wet chlorine and hypochlorite. |
|---|---|
| Typical service | Chemical processing — Reactors, heat exchangers and piping for mixed acids. |
| B16.5 material group | 3.8 |
| Bolting | B7 (coated), B8M or nickel-alloy studs such as Hastelloy C276 from ASTM B574, as the project specifies |
| Welding to carbon steel | A nickel-base filler such as ERNiCr-3 (or ERNiCrMo-3) is used when joining it to carbon steel |
| Matching filler | ERNiCrMo-4 (AWS A5.14) |
| Sour service | Listed in NACE MR0175 / ISO 15156-3 within its limits — state it on the order |
Hastelloy C276 Spectacle Blind Chemical Composition
| Element | Weight % |
|---|---|
| Nickel | Balance |
| Molybdenum | 15.0 – 17.0 |
| Chromium | 14.5 – 16.5 |
| Iron | 4.0 – 7.0 |
| Tungsten | 3.0 – 4.5 |
| Cobalt | 2.5 max |
| Carbon | 0.010 max |
| Manganese | 1.0 max |
Hastelloy C276 Spectacle Blind Mechanical Properties
| Solution-annealed plate & sheet | Value |
|---|---|
| Tensile strength | 690 MPa · 100 ksi |
| Yield strength 0.2% | 283 MPa · 41 ksi |
| Elongation | 40% |
Full chemistry, properties and equivalents are on the Hastelloy C276 grade page.
Other Hastelloy C276 flanges
Hastelloy C276 Spectacle Blinds for export
FOB / CIF · Nhava Sheva (JNPT), MumbaiHastelloy C276 Spectacle Blind — questions buyers ask
When should I use a spacer and paddle blank instead of a spectacle blind?
In large sizes a spectacle blind becomes too heavy and awkward, so ASME B16.48 provides separate paddle blanks and spacers.
What pressure rating does a Hastelloy C276 spectacle blind have?
It depends on class and temperature. Hastelloy C276 forgings are in ASME B16.5 material group 3.8; read your class column in that group's table at the design temperature.
Can Hastelloy C276 spectacle blinds be welded to carbon steel?
Yes — a nickel-base filler such as ERNiCr-3 (or ERNiCrMo-3) is used when joining it to carbon steel.
Which standard covers Hastelloy C276 spectacle blinds?
The material is ASTM B462 / B564; dimensions follow ASME B16.48. Always state both on your purchase order, with the edition if your project specifies one.
What decides the price of a Hastelloy C276 spectacle blind?
The alloy price, the size and pressure class, quantity, and the testing and documents required. Send your list and we quote the same working day.
Can you supply Hastelloy C276 spectacle blinds to NACE MR0175?
Yes. Hastelloy C276 is listed in NACE MR0175 / ISO 15156-3 within its limits; state NACE compliance on the order and it is confirmed on the certificate.
What documents do you supply?
EN 10204 3.1 mill certificates as standard, 3.2 with third-party inspection on request, plus dimensional and PMI reports.
Sources: the ASTM / ASME specifications named on this page and producer datasheets · Last updated October 2026