Flare fitting

Flare fittings are a type of compression fitting used with metal tubing, usually ductile (soft) copper, though other materials are also used.

Tube flaring is considered a forging operation. [Manufacturing and Engineering Technology: Serope Kalpakjin] It is usually a cold working operation but can be done hot.Tube flaring is primarily used to hold a special flare nut in place so the tube may be connected to other components.

The tool used to flare tubes consists of a die that holds the tube and a mandrel that is inserted into the tube to enlarge the diameter, the cross section is also deformed by this process The nut is then tightened, compressing the flared portion of the tubing between the male fitting and the nut. Flare fittings offer a high degree of long term reliability and for this reason are often used in mission-critical and inaccessible locations.

There are several styles of flare fitting available, including the 45° SAE style (available at many hardware stores, and very commonly used), the 37° AN style, and JIC. Note that 45° and 37° flare fittings and tools are incompatible and should not be mixed.

References

See also

* Compression fitting
* Pipe fitting
* Sweat fitting