Inconel 625 Spectacle BlindASTM B564 · ASME B16.48 · Manufacturer, stockist & exporter, India
Alloy 625 · UNS N06625 · SB
An Inconel 625 spectacle blind is a figure-8 plate with one solid end and one open ring, fitted between two flanges, made from Inconel 625 to ASTM 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 B564
- 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 an Inconel 625 Spectacle Blind?
- What it is
- A figure-8 plate with one solid end and one open ring, fitted between two flanges
- Material
- ASTM B564
- Dimensions
- ASME B16.48
- Grade
- Inconel 625 · UNS N06625
- Best at
- Seawater, high strength and high temperature in one alloy
Inconel 625 Spectacle Blind Specification
| Product | Inconel 625 Spectacle Blind |
|---|---|
| Material standard | ASTM 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.
Inconel 625 Spectacle Blind: Why 625 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 Inconel 625, 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. Inconel 625 is picked for seawater, high strength and high temperature in one alloy. |
|---|---|
| Typical service | Offshore & subsea — Risers, flowlines and clad pipe. |
| B16.5 material group | 3.8 |
| Bolting | B7 (coated), B8M or nickel-alloy studs such as Inconel 625 from ASTM B446, 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-3 (AWS A5.14) |
| Sour service | Listed in NACE MR0175 / ISO 15156-3 within its limits — state it on the order |
Inconel 625 Spectacle Blind Chemical Composition
| Element | Weight % |
|---|---|
| Nickel | 58.0 min |
| Chromium | 20.0 – 23.0 |
| Molybdenum | 8.0 – 10.0 |
| Niobium + Tantalum | 3.15 – 4.15 |
| Iron | 5.0 max |
| Carbon | 0.10 max |
| Manganese | 0.50 max |
| Silicon | 0.50 max |
Inconel 625 Spectacle Blind Mechanical Properties
| Grade 1 annealed plate | Value |
|---|---|
| Tensile strength | 827 MPa · 120 ksi |
| Yield strength 0.2% | 414 MPa · 60 ksi |
| Elongation | 30% |
Full chemistry, properties and equivalents are on the Inconel 625 grade page.
Other Inconel 625 flanges
Inconel 625 Spectacle Blinds for export
FOB / CIF · Nhava Sheva (JNPT), MumbaiInconel 625 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 Inconel 625 spectacle blind have?
It depends on class and temperature. Inconel 625 forgings are in ASME B16.5 material group 3.8; read your class column in that group's table at the design temperature.
Can Inconel 625 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 Inconel 625 spectacle blinds?
The material is ASTM 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 Inconel 625 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 Inconel 625 spectacle blinds to NACE MR0175?
Yes. Inconel 625 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