JIC Fitting Sizes Overview

JIC fittings are common with high-pressure hydraulic systems. These fittings usually feature parallel threads with a 37-degree flare seating surface. Materials used for JIC fittings vary. The most common of which are nickel alloys, brass, carbon, and stainless steel.

As with any hydraulic fitting type, JIC fittings are available in different sizes. The size of a hydraulic fitting is one of the most important factors when making a purchase.

It is essential to use a hydraulic fitting whose size matches the hose, pipe, or tube it will connect with. Otherwise, the hydraulic system would not function properly, and accidents might occur.

In this post, we look at the different JIC fitting sizes. With this information, identifying the right JIC fitting size for your hydraulic system becomes easier.

Sizes of JIC Fittings

The JIC fitting size you need depends on the outer diameter of the tube you are connecting with. The tube usually has inches or metric size and requires a nut and sleeve during installation.

So, you have to consider dash size, thread size, and threads per inch when purchasing JIC fittings. The inner diameter of the female thread and the outer diameter of the male thread are also critical.

Check the below chart for the different sizes of JIC fittings:

	Dash Size	Male Thread Outer Diameter	Female Thread Inner Diameter	Thread Size	Threads Per Inch
1.	-2	7.9 mm	6.7 mm	5/16	24
2.	-3	9.5 mm	8.3 mm	3/8	24
3.	-4	11.1 mm	9.9 mm	7/16	20
4.	-5	12.7 mm	11.5 mm	1/2	20
5.	-6	14.3 mm	12.7 mm	9/16	18
6.	-8	19.1 mm	17.5 mm	3/4	16
7.	-10	22.2 mm	20.6 mm	7/8	14
8.	-12	27.0 mm	24.6 mm	1-1/16	12
9.	-14	30.2 mm	28.2 mm	1-3/16	12
10.	-16	33.3 mm	31.4 mm	1-5/16	12
11.	-20	41.3 mm	39.3 mm	1-5/8	12
12.	-24	47.6 mm	45.6 mm	1-7/8	12
13.	-32	63.5 mm	61.5 mm	2-1/2	12

How Are JIC Fittings Different From Other Fittings

The standard they follow is the primary difference between JIC fittings and the other fitting types in the market. JIC fittings follow the standards laid out by the Joint Industry Council. 

Meanwhile, NPT fittings, for example, follow the US standard, and BSP follows British standards. Another popular type is the SAE fitting, which follows the Society of Automotive Engineers standards.

Compared to NPT fittings, JIC fittings are better sealers. As mentioned earlier, JIC fittings have a 37-degree flare seating surface. The same is not true for NPT fittings, which only have tapered threads.

Since they have tapered threads, NPT fittings work with larger inner and outer diameters than JIC fittings. From the chart above, the 2-dash-size male outer diameter of a JIC fitting is 7.9 mm. For NPT fittings, the male outer diameter of the same dash size is 10.3 mm.

BSP fittings are more similar to JIC fittings considering their use case. Both fitting types are high-pressure fittings and usually pass as thrust-wire fittings.

In addition, both come in 2 to 48-dash sizes. But note that BSP fittings and JIC fittings are not interchangeable. While they share similar dash sizes, the thread sizes and diameters differ.

Like the BSP firings, SAE fittings are similar to JIC fittings. SAE and JIC fittings look the same and share the same thread size for most dash sizes. In particular, the thread size is the same for 2 to 10-dash sizes.

Yet, SAE and JIC fittings are still not interchangeable. This is because they feature different flare angles. SAE fittings usually come with a 45-degree flare angle, which differs from JIC’s 37-degree.

What Fitting Standards Are Interchangeable With JIC Fittings?

JIC fittings are considered interchangeable with AN thread fittings. In truth, they are interchangeable, but not in all situations.

AN, or Air Navy, fittings are common for military aviation and aerospace applications. But JIC fittings are not accepted in such applications. Instead, JIC fittings are common in construction equipment and heavy machinery applications.

Both JIC and AN fittings have the same 37-degree flare angle. However, JIC fittings have a lower class of thread quality, which is why they do not work for the same applications as AN fittings.

You may need a UNF thread to interchange a JIC fitting for an AN fitting. Also, cross-check the dash size, thread size, inner diameter, and outside diameter to be sure they match.

JIC fittings are also interchangeable with some SAE fittings. The majority of SAE fittings you will find come with a 45-degree flare angle. However, it is possible to get an SAE fitting with a 37-degree flare angle like the JIC fittings.

In general, interchanging hydraulic fittings is not recommended. Always try to get the correct type of fittings for your hydraulic system.

Talk to an Industry Professional for Your JIC Fittings

Now that you know the different sizes of JIC fittings, you will find it easy to purchase the correct fitting for your hydraulic system.

If you need more guidance or have questions, the best thing to do is talk to an industry expert. Contact us at Sinoplulse Group today, our experts are here to assist you.