JIC fittings, defined by the SAE J514 and MIL-F-18866 standards, are a type of flare fitting

Flare fitting

Flare fittings are a type of compression fitting used with metal tubing, usually soft steel and ductile copper, though other materials are also used.  Tube flaring is considered to be a type of forging operation, and is usually a cold working procedure.  During assembly, a flare nut is...

 machined with a 37-degree flare seating surface.  JIC (Joint Industry Council) fittings are widely used in fuel delivery and fluid power

Hydraulics

Hydraulics is a topic in applied science and engineering dealing with the mechanical properties of liquids. Fluid mechanics provides the theoretical foundation for hydraulics, which focuses on the engineering uses of fluid properties. In fluid power, hydraulics is used for the generation, control,...

 applications, especially where extremely high pressure is involved.  The SAE J514 standard replaces the MS16142 military specification, although some tooling is still listed under MS16142.  JIC fittings are dimensionally identical to AN (Army-Navy)

AN thread

The AN thread is a particular type of fitting used to connect flexible hoses and rigid metal tubing that carry fluid. It is a US military-derived specification that dates back to World War II and stems from a joint standard agreed upon by the Army and Navy, hence AN.AN sizes range from -2 to -32...

 fittings, but are produced to less exacting tolerances and are generally less costly.  45-degree flare fittings are similar in appearance, but are not interchangeable.

JIC fitting systems have three components that make a tubing assembly: fitting, flare nut, and sleeve.  As with other flared connection systems, the seal is achieved through metal-to-metal contact between the finished surface of the fitting nose and the inside diameter of the flared tubing.  The sleeve is used to evenly distribute the compressive forces of the flare nut to the flared end of the tube.  Materials commonly used to fabricate JIC fittings include forged

Forging

Forging is a manufacturing process involving the shaping of metal using localized compressive forces. Forging is often classified according to the temperature at which it is performed: '"cold," "warm," or "hot" forging. Forged parts can range in weight from less than a kilogram to 580 metric tons...

 carbon steel, forged stainless steel

Stainless steel

In metallurgy, stainless steel, also known as inox steel or inox from French "inoxydable", is defined as a steel alloy with a minimum of 10.5 or 11% chromium content by mass....

, forged brass

Brass

Brass is an alloy of copper and zinc; the proportions of zinc and copper can be varied to create a range of brasses with varying properties.In comparison, bronze is principally an alloy of copper and tin...

, machined brass, Monel

Monel

Monel is a trademark of Special Metals Corporation for a series of nickel alloys, primarily composed of nickel and copper, with some iron and other trace elements. Monel was created by David H. Browne, chief metallurgist for International Nickel Co...

 and nickel-copper

Cupronickel

Cupronickel or copper-nickel or "cupernickel" is an alloy of copper that contains nickel and strengthening elements, such as iron and manganese. Cupronickel is highly resistant to corrosion in seawater, because its electrode potential is adjusted to be neutral with regard to seawater...

alloys.