JIC fittings (also known as SAE 37° tube fittings, flared fittings, or SAE J514 fittings) are one of the most popular configurations of hydraulic fluid connectors in North America, thanks to their exceptional seal and versatility.
In this blog, we’ll provide an introduction to JIC fittings, exploring their purpose, versatility, and application.
What Are JIC Fittings?
Most commonly used as hydraulic fittings in the fluid power industry, JIC (Joint Industry Council) fittings are a type of flare fitting machined with straight threads using a 37° flare seating surface. This is used to form the seal of the fitting instead of an o-ring or tapered threads. Though they have identical dimensions, JIC fittings should not be confused with AN (Army Navy) fittings, and the two should not be considered functionally interchangeable.
JIC fittings consist of three main parts: body, nut, and sleeve. The seal in JIC fittings is created through the metal-to-metal contact of the finished surface of the fitting nose and the inside of the flared tubing. The fitting sleeve supports the connection between the fitting nose and the inside of the flared tubing by distributing the compression during assembly. Higher quality finishes are less likely to leak since they don’t contain as many irregularities in craftsmanship.
JIC fittings can perform at pressures up to 7,700 psi and at temperatures ranging from -425°F to 1200°F, depending on the material. In most applications, they can handle moderate vibration environments, though enhanced versions can exceed these pressure, temperature, and vibration requirements.
Advantages of JIC Fittings
JIC fittings offer many of the same advantages as other fittings and seals as well as additional unique benefits.
Universal & Affordable
The simplicity and affordability of manufacturing JIC fittings—as well as the wide range of size and style options—have made them the industry standard for hydraulic fittings for decades. JIC fittings now come in a multitude of variations that are easy to adapt to both imperial and metric, allowing them to fit virtually any hose or port and making them universally accepted by both foreign and American companies.
High/Low Temperature Performance
JIC fittings perform exceptionally well in high- and low-temperature environments. The metal-to-metal seal found in JIC fittings is not affected by temperature like O-rings are, since O-rings are typically made of rubber or some other elastomer material that can handle exposure to a milder range of temperatures.
Beyond the versatility that allows JIC fittings to be connected to virtually any hydraulic system, JIC fittings can also be disconnected (and later reconnected) without loss in performance, further explaining how they came to be an industry standard.
Typical Applications of JIC Fittings
Today, JIC fittings are most commonly found in the military, aerospace, and plumbing industries.
In the past, JIC fittings were also referred to by the military specification MIL-F-18866. While that specification has been superseded by SAE J514, many industries and their designers continue to refer to JIC fittings in this way. In the military today, JIC fittings are primarily used in fuel delivery applications, connecting control valves with hydraulic tubing.
JIC fittings see heavy use in the aerospace industry by commercial airline manufacturers, NASA, and privately owned space companies. They can be found in commercial airliners, airline ground equipment, and aerospace fluid systems.
JIC fittings also see use in flexible plumbing systems joining together tubing in a hydraulic system. They can be attached to a hose as an adapter for female SAE swivels, allowing versatility and flexibility wherever necessary within the system.
JIC Fittings From SSP
At SSP, we have a long history of manufacturing experience crafting fluid system components and assemblies, including JIC fittings. A great source of pride is our excellence in and dedication to customer service. We are committed to our clients, regardless of company size or order size, and we guarantee unparalleled products with the technical knowledge to comprehensively service them.
Our JIC fittings are available in two styles: SAE 37° Flared and the modified UltraFlare version, which includes a primary PTFE seal, reinforced by the metal-on-metal seal which increases performance in mild vacuum and moderate vibration on thin and medium-walled tubing systems. To learn more about JIC fittings or our products and capabilities, reach out to us today.