2" UNS C70600 Copper Nickel Weld Neck Flange ASTM B466 Marine Pipeline

Product Specification

2" UNS C70600 Copper Nickel Weld Neck Flange ASTM B466 Marine Pipeline Connecting Flange

1. Product Description

This product is a Weld Neck (WN) flange manufactured from UNS C70600 (90/10 Copper-Nickel alloy / CuNi 90/10) in accordance with ASTM B466 and ASME B16.5 standards. UNS C70600, also known as CuNi10Fe1Mn or DIN 2.0872, is the most widely used marine copper-nickel grade, prized for its outstanding seawater corrosion resistance and natural antifouling behaviour. The Weld Neck flange features a tapered hub that transitions smoothly to the pipe wall, providing high strength and sealing reliability. This 2" flange is designed for permanent butt-weld connection in demanding marine and offshore pipeline systems.

2. Key Product Parameters

3. Application / Usage

This Weld Neck flange is ideal for seawater and corrosive fluid systems in demanding environments:

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

• Offshore Oil & Gas: Seawater lift pipes, platform cooling water ring mains, subsea piping

• 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 cannot be used

4. Advantages

• Superior Seawater Corrosion Resistance: Exceptional resistance to pitting, crevice corrosion, and chloride stress-corrosion cracking in marine environments

• Natural Antifouling Behaviour: Copper content inhibits marine biological growth, keeping pipe bores clear without coatings

• Weld Neck Design: Tapered hub provides smooth stress transition, excellent resistance to fatigue and thermal cycling

• High Strength & Reliability: Maintains good mechanical properties at moderate and elevated temperatures, and retains ductility at cryogenic temperatures

• Excellent Weldability: Single-phase alpha structure enables outstanding fabrication properties without complex preheating

5. Functions

The Weld Neck flange provides a permanent, leak-proof bolted connection point for joining pipes, valves, or equipment in a piping system. The tapered neck is butt-welded to the pipe, forming a unified structure that distributes stress evenly and minimizes pressure concentration at the joint. The flange face (typically Raised Face) accommodates a gasket to ensure a reliable seal when bolted to a mating flange.

6. Installation Instructions

1. Unpacking Inspection: Check for transit damage; verify markings and dimensions per ASME B16.5

2. Surface Preparation: Clean the weld bevel and adjacent area using a stainless steel wire brush; remove all oil, grease, and oxidation

3. Alignment: Accurately align the flange neck with the pipe end, ensuring proper fit-up and squareness

4. Welding: Use GTAW (TIG) process with matching ERCuNi filler wire (AWS A5.7). Use 100% argon shielding; back purge recommended for root pass. Preheat generally not required; interpass temperature ≤150°C. No post-weld heat treatment required

5. Gasket Installation: Place a suitable gasket (e.g., spiral wound, PTFE) on the flange face

6. Bolting: Install bolts and tighten in a cross-torque sequence to the recommended torque value

7. Hydrotest: Test pressure = 1.5 × design pressure; ambient temperature not below 5°C

7. Precautions

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

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

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

• Bolting Torque: Do not exceed recommended torque to prevent gasket damage or flange distortion

• Gasket Selection: Choose gasket material compatible with the service medium and pressure/temperature conditions

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

• PMI and 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.