Copper-nickel flanges are commonly used in various industrial applications, particularly in maritime and offshore industries, due to their excellent corrosion resistance and high durability. The main objectives of using copper-nickel flanges are as follows:

1. Corrosion Resistance: One of the primary objectives of using copper-nickel flanges is their exceptional resistance to corrosion, especially in seawater and marine environments. They are highly resistant to both saltwater corrosion (biofouling) and general corrosion, making them ideal for marine and offshore applications.
2. Longevity and Durability: Copper-nickel flanges are known for their long service life and durability. They can withstand the harsh conditions of saltwater, aggressive chemicals, and extreme temperatures, ensuring that the flanges maintain their integrity and functionality over an extended period.
3. Reliability and Safety: Copper-nickel flanges are used in critical applications where reliability and safety are paramount. They are chosen for their ability to maintain structural integrity, even in challenging conditions, reducing the risk of leaks, failures, and accidents.
4. Ease of Fabrication: Copper-nickel alloys, including Cu-Ni 90/10 (90% copper, 10% nickel) and Cu-Ni 70/30 (70% copper, 30% nickel), are known for their excellent workability and ease of fabrication. This makes it relatively straightforward for manufacturers to produce flanges of various shapes and sizes to meet specific project requirements.
5. Compatibility with Seawater: Copper-nickel alloys are well-suited for use in seawater systems, where they prevent biofouling and corrosion. They also exhibit low susceptibility to stress corrosion cracking and erosion, ensuring the long-term functionality of components like flanges in marine and offshore applications.

In summary, the main objectives of using copper-nickel flanges revolve around their exceptional corrosion resistance, longevity, reliability, ease of fabrication, and compatibility with seawater, making them a preferred choice for demanding industrial and marine applications.