Monel K500 Spectacle BlindASTM B865 · ASME B16.48 · Manufacturer, stockist & exporter, India
Alloy K-500 · UNS N05500 · SB
A Monel K500 spectacle blind is a figure-8 plate with one solid end and one open ring, fitted between two flanges, made from Monel K500 to ASTM B865. 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 B865
- 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 Monel K500 Spectacle Blind?
- What it is
- A figure-8 plate with one solid end and one open ring, fitted between two flanges
- Material
- ASTM B865
- Dimensions
- ASME B16.48
- Grade
- Monel K500 · UNS N05500
- Best at
- High-strength pump shafts, bolting and springs in seawater
Monel K500 Spectacle Blind Specification
| Product | Monel K500 Spectacle Blind |
|---|---|
| Material standard | ASTM B865 |
| 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.
Monel K500 Spectacle Blind: Why K500 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 Monel K500, 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. Monel K500 is picked for high-strength pump shafts, bolting and springs in seawater. |
|---|---|
| Typical service | Marine — Propeller and pump shafts. |
| Bolting | B7 (coated), B8M or nickel-alloy studs such as Monel K500 from ASTM B865, 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 | ERNiCu-7 (non-ageing) |
| Sour service | Listed in NACE MR0175 / ISO 15156-3 within its limits — state it on the order |
Monel K500 Spectacle Blind Chemical Composition
| Element | Weight % |
|---|---|
| Nickel (+Co) | 63.0 min |
| Copper | 27.0 – 33.0 |
| Aluminium | 2.30 – 3.15 |
| Titanium | 0.35 – 0.85 |
| Iron | 2.0 max |
| Manganese | 1.5 max |
| Carbon | 0.25 max |
| Silicon | 0.5 max |
Monel K500 Spectacle Blind Mechanical Properties
| Age-hardened bar | Value |
|---|---|
| Tensile strength | 965 MPa · 140 ksi |
| Yield strength 0.2% | 690 MPa · 100 ksi |
| Elongation | 20% |
Full chemistry, properties and equivalents are on the Monel K500 grade page.
Other Monel K500 flanges
Monel K500 Spectacle Blinds for export
FOB / CIF · Nhava Sheva (JNPT), MumbaiMonel K500 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.
Can Monel K500 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 Monel K500 spectacle blinds?
The material is ASTM B865; 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 Monel K500 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 Monel K500 spectacle blinds to NACE MR0175?
Yes. Monel K500 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