The Flared Connection.
This connection withstands high pressure
and is used extensively in hydraulic systems.
The component pieces
necessary to form a flared connection are a nut, sleeve, and properly
formed (flared) tube end.
These pieces are assembled with the nut
screwed on a threaded fitting. These nuts and sleeves are available
in both steel and aluminum alloy; the use varies with the material of
the tube. Two types of flares can be made on tubing: