Flare fitting is a compression fitting used with metal pipe, usually carbon steel, ductile (soft) brass, and aluminum, but other materials are also used. In flare fittings, the tube itself is flare, that is, expanded and deformed at the ends of the tube. The male flare union is then pressed against the fitting to which it is attached and secured with a tight-fitting nut to ensure no leakage occurs.
Tube flaring is a forging operation, usually a cold working operation. During assembly, a flared nut is used to secure the tapered end of the flared tube to an equally tapered fitting, crebility and are therefore often used in mission-critical and inaccessible locations. Tools for flared joints consist a pressure-resistant, leak-proof seal. Flare connection is a kind of long-term reliable way of connection, and usually used for a hard task or not easy reachable position. The tools for production of male flare union is a die which can grip the tube, and a mandrel or rolling cone pressed into the end of the tube to form the flare by cold working.
The most common flare fitting standards using today are 45° SAE flare, 37°JIC flare, and 37°AN flare. SAE 45° flare connections are commonly used in automotive applications as well as refrigeration and air conditioning. SAE fittings are usually made of brass. SAE and AN/JIC connections are not compatible due to different opening angles. JIC 37° torch connection for high pressure hydraulic applications. JIC fittings are usually steel or stainless steel. Due to different quality standards, JIC accessories are not allowed when AN connection is specified.
