Cooper Nickel Spectacle Blind ASTM B466 UNS C71500 4" ASME B16.48 Anti Corrosion

Product Specification

Cooper Nickel Spectacle Blind ASTM B466 UNS C71500 4" ASME B16.48 Anti Corrosion

1. Product Description

This product is a spectacle blind (also known as a figure-8 blind) manufactured from UNS C71500 (70/30 Copper-Nickel alloy / CuNi 70/30) in accordance with ASTM B466 and ASME B16.48 standards. A spectacle blind is a permanent piping isolation device consisting of two metal discs connected by a short tie bar: one solid disc (the blind) and one open disc with a bore (the ring spacer). The figure-eight shape resembles a pair of spectacles, giving it its name. UNS C71500, also known as CuNi 70/30 or Werkstoff Nr. 2.0882, contains approximately 70% copper and 30% nickel, with small additions of iron and manganese to enhance strength and corrosion resistance. This 4" flange is designed for installation between two ASME B16.5 flanges to provide positive isolation for equipment or pipeline sections requiring inspection, maintenance, or removal from service.

2. Key Product Parameters

3. Application / Usage

This spectacle blind is ideal for seawater and corrosive fluid systems requiring positive isolation:

• Marine & Shipbuilding: Seawater cooling systems, firewater lines, ballast systems

• Offshore Oil & Gas: Platform piping, subsea applications, seawater injection

• Desalination Plants: Seawater intake, reverse osmosis feed lines, brine recirculation

• Power Generation: Condenser cooling water systems, heat exchangers

• Chemical Processing: Chloride-containing environments where stainless steel may suffer SCC

• Equipment Isolation: Upstream/downstream of heat exchangers, vessels, pumps requiring maintenance

4. Advantages

• Positive Isolation: Provides absolute, zero-leakage isolation—more reliable than valves which can leak or be accidentally opened

• Superior Corrosion Resistance: Exceptional resistance to seawater, pitting, crevice corrosion, stress corrosion cracking, and hydrogen embrittlement

• Biofouling Resistance: Copper content naturally inhibits marine biological growth

• Visual Indication: The protruding handle/tab visibly confirms whether the line is open or blinded

• Permanent Installation: Remains in the piping system throughout its service life; no separate storage required for blind and spacer

• Easy Switching: Rotate 180 degrees to change from open to closed position without removing the fitting

• High Strength: 70/30 CuNi offers better strength and erosion resistance than 90/10 CuNi

5. Functions

The spectacle blind provides a permanent, leak-proof isolation device for piping systems. In the “open” position, the ring spacer with a bore matching the pipe ID sits between the flanges, allowing full flow. In the “closed” position, the assembly is rotated 180 degrees so the solid blind disc sits between the flanges, completely blocking flow. The unused disc hangs outside the flange pair, visible to operators as a visual confirmation of the line status. Two gaskets are required—one on each side of the active disc.

6. Installation Instructions

1. Unpacking Inspection: Check for transit damage; verify markings, dimensions, and pressure class per ASME B16.48

2. Surface Preparation: Clean the spectacle blind and flange faces using dedicated tools; remove all oil, grease, and contaminants

3. Flange Preparation: Depressurize and drain the line section; unbolt the flange pair and spread the flanges apart

4. Gasket Installation: Place new gaskets on both sides of the spectacle blind (one on each face of the active disc)

5. Positioning: For normal operation, position the ring spacer between the flanges (open position). For isolation, rotate 180 degrees to position the solid blind disc (closed position)

6. Bolting: Install longer stud bolts (to accommodate the additional thickness of the spectacle blind and two gaskets). Tighten in a cross-torque sequence to the recommended torque value

7. Verification: Confirm the protruding handle/tab visibly indicates the correct position (spacer = open; blind = closed)

7. Precautions

• Cleanliness: Requires a higher degree of cleanliness than carbon steel fabrication; use dedicated tools to prevent contamination

• Temperature Limit: For aqueous corrosion service, verify system conditions for temperatures above 300°C

• Gasket Requirement: Two gaskets are mandatory—one on each side of the active disc

• Bolting: Longer stud bolts are required due to the additional thickness of the spectacle blind and two gaskets

• Medium Compatibility: Not recommended for use with strong oxidizing acids (e.g., nitric acid) or ammonia systems

• Space Requirement: The installation must accommodate the full swing of the spectacle blind for 180-degree rotation

• Handle Indication: The protruding handle is the primary visual indicator of line status—ensure it is clearly visible and properly identified

8. Shipping & Delivery

• Standard delivery time is typically 15–30 days, subject to order quantity, pressure class, and specification availability

9. Payment Terms

• Common international payment methods include T/T (Telegraphic Transfer) and L/C at sight (Letter of Credit)

10. Packaging

• Products are securely packed in plywood cases or wooden crates with internal cushioning to ensure safe transportation and prevent damage during transit

11. After-Sales / Return & Warranty Policy

• All products undergo strict quality inspection before shipment, with Mill Test Certificates (EN 10204 3.1/3.2) available

• Third-party inspection (ABS, DNV, CCS, LR, BV, etc.) available upon request

• In case of quality issues, retain original packaging and provide relevant photos or third-party inspection reports

• Specific return, exchange, and warranty terms are subject to the final sales contract agreement.

  FAQ

  1. Are you trading company or manufacturer ?
      We are manufacturer ,You can see the certification.
  2. How long is your delivery time?
      Generally it is 5-10 days if the goods are in stock. or it is 15-20 days if the goods are not in stock, it is according to quantity.
  3. Do you provide samples ? is it free or extra ?
      Yes, we could offer the sample for free charge but need pay the cost of freight.
  4. What is your terms of payment ?
      Payment<=1000USD, 100% in advance. Payment>=1000USD, 50% T/T in advance ,balance before shippment.