CuNi 70/30 Copper Nickel Elbow 90° BW ASME B16.9 Corrosion Resistant Seamless Fitting

CuNi 70/30 Copper Nickel Elbow 90° BW ASME B16.9 Corrosion Resistant Seamless Fitting

The Copper Nickel Elbow is a directional pipe fitting manufactured from Cu-Ni alloys (grades C70600 90/10 and C71500 70/30) via cold extrusion, hot pushing, or integral die forging. Both grades possess a face-centered cubic solid-solution microstructure, offering excellent work-hardening characteristics and corrosion resistance. The elbows feature smoothly curved sections with beveled or threaded ends machined in accordance with ASME/EN/DIN standards, with wall thickness tolerance within ±12.5% and ovality ≤8% to ensure seamless integration with piping systems. Each elbow undergoes intergranular corrosion testing, hydrostatic testing, and non-destructive inspection, with full traceability to the original melt lot.

2.Product Applications

This product is specifically engineered for severe corrosive services. Primary applications include:

Marine & Offshore: Sea-water intake lines, bilge discharge, fire mains, ballast water treatment systems, and cooling water headers on vessels and platforms.

Desalination & Water Treatment: Brine circulation lines in Multi-Stage Flash (MSF) units, and feed/discharge pipes in Reverse Osmosis (RO) plants.

Power Generation: Auxiliary cooling water systems in nuclear and coastal thermal power plants, condenser tube bundles, and heat exchanger bypasses.

Chemical & Petrochemical: Transport of acetic acid, phosphoric acid, organic acids, chlorinated solvents, and hydrochloric acid recovery (subject to concentration/temperature limits).

Offshore Engineering: Scour protection pipes for offshore wind foundations, and directional turns in subsea manifolds.

3.Product Advantages

1. Seawater Impingement Resistance: In seawater with flow velocities up to 3.5 m/s, C70600 exhibits corrosion rates of only 0.002–0.005 mm/a and withstands cavitation erosion better than standard copper alloys.

2. MIC Resistance: Copper ion release creates a bio-inhibitive layer, effectively preventing microbiologically influenced corrosion (MIC) caused by sulfate-reducing bacteria (SRB), thereby reducing clogging risks.

3. Weld Joint Corrosion Integrity: When welded with matching filler (e.g., ERCuNi-7), the weld zone retains corrosion resistance comparable to the base metal with no post-weld heat treatment required.

4. Low-Temperature Toughness: Maintains excellent impact toughness (≥60 J) down to –196°C, making it suitable for LNG-related cryogenic seawater systems.

5. Dimensional Stability and Workability: Hot-pushing refines grains, minimizes spring-back, and ensures high dimensional accuracy, eliminating field trimming.

6. Low Life‑Cycle Cost: Higher initial cost than carbon steel or galvanized piping, but over a 25‑ to 30‑year service life, maintenance costs are reduced by 40%–60%, and the alloy is fully recyclable.

​4.Key Product Specifications

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