most common flare fitting standards in use today are the 45° SAE flare, the 37° JIC flare, and the 37° AN flare.

For high pressure, flare joints are made by doubling the tube wall material over itself before the bell end is formed. The double flare avoids stretching the cut end where a single flare may crack. Before the flaring step, the end of the tube is compressed axially causing the tube wall to yield