September 23, 2020 209
In the hydraulics industry, JIC and AN fittings are terms thrown around and searched for online interchangeably. But, are they? Are a JIC and AN hydraulic fitting the same thing? And if not, what’s the difference? NJ digs in.
Historical Context of the AN Fitting
AN stands for Air Force – Navy Aeronautical Design Standards (also known as “Army Navy”) that are used in U.S. Military aviation applications. These fittings are made to meet strict performance standards related to the aeronautical industry. The use of "AN" fittings increased to include most branches of U.S. Military, Military Contractors, General Aviation and Commercial Aviation. As these fittings were adopted for use in many land and sea applications, confusion between AN and its industrial counterpart, the SAE 37 degree fitting occurred. In the 1960s, several versions of 37 degree flare fittings flooded the industrial market, all claiming the AN standard, creating a nightmare for the users.
JIC Steps In
The Joint Industries Council (JIC), sought to clear the air by standardizing the specifications on this type of fitting by creating the "JIC" fitting standard, a 37-degree fitting with a slightly lower class of thread quality than the military AN version. The SAE went on to adopt this JIC standard as well. It’s important to note that the AN and JIC specifications are no longer in existence in most cases.
The majority of the hydraulic population agrees, the JIC (or SAE) 37 degree fittings are generally interchangeable with AN fittings. Keep in mind that JIC fittings are not acceptable for military aviation or aerospace use, but for agricultural equipment, construction equipment, heavy machinery applications or material handling and the like, JIC / SAE adapters are the same. And it’s worth noting that the JIC fittings are a fraction of the price of their true "AN" counterparts.
Technically speaking, AN fittings are manufactured to MIL-F-5509, and industrial 37-degree flare fittings are manufactured to meet SAE J514/ISO-8434-2.
The most notable difference between these standards are in the threads. AN fittings use an increased root radius thread (“J” thread) and a tighter tolerance (Class 3) to achieve a 40% increase in fatigue strength and 10% increase in shear strength. Material requirements also differ greatly. These two fittings function the same, they look the same, AND the industrial version is much less expensive to manufacturer. The “JIC” / SAE J514 fittings produced by NJ satisfy all of qualification requirements specified.