Threaded pipe and fittings can be connected and disconnected as needed for maintenance and repair.

Weld fittings to pipe for a permanent connection. Welded connections are stronger than threaded connections and are less likely to leak.

Aluminum has good corrosion resistance and is lightweight.

Copper-nickel has excellent resistance to stress cracking and has better corrosion resistance than most stainless steel alloys. It can stand up to corrosive environments, such as salt water applications.