Look at the sealing end. A JIC fitting has a 37° cone, an ORB male has an O-ring behind straight threads and screws into a port, and an ORFS male has an O-ring in its flat face.
| JIC 37° | ORB (O-ring boss) | ORFS (O-ring face seal) | |
|---|---|---|---|
| Seals with | Metal to metal, on a 37° flare | The male’s O-ring, against the port’s sealing face | An O-ring in a groove in the male’s flat face |
| Male end | A 37° cone on the nose | Straight threads with an O-ring at their base | A flat face with an O-ring in it |
| Female end | A swivel nut with a 37° seat | A port in the machine (the boss) | A swivel nut with a flat face |
| Thread | UNF, the same as ORB at every size | UNF, the same as JIC at every size | UNF, a size up from JIC |
| -8 thread | 3/4-16 | 3/4-16 | 13/16-16 |
| Standards | ISO 12151-5, ISO 8434-2, SAE J516 | SAE J1926 | ISO 12151-1, ISO 8434-3, SAE J516 |
How to tell them apart in your hand
- Find the seal on a male end. A cone on the nose is JIC, or SAE 45°, which a seat gauge separates. An O-ring at the base of the threads is ORB. An O-ring set into the flat end is ORFS.
- Look inside a female swivel nut. A cone-shaped seat means JIC, and a flat face means ORFS. ORB has no hose-end female: its female is the port in the machine.
- Then measure for the size. Count the threads per inch and measure across them, and look the thread up in the hydraulic thread chart. JIC and ORB share every thread, so the size alone won’t tell those two apart.
Why they don’t mix
A JIC male and an ORB male of the same dash size have the same thread, so a JIC fitting will screw into an ORB port, but it has no O-ring to seal there. An ORB male is made only for the boss-type ports found in machines. ORFS is a size off: a -4 ORFS shares the 9/16-18 thread of a -6 JIC, yet one seals on a flat face and the other on a cone.
Adapters between them
- ORB port to a JIC hose: a straight adapter with an ORB male end and a JIC male end. Parker’s is the F5OX: a -6 hose on a -8 port takes a 6-8 F5OX.
- ORB port to an ORFS hose: an ORB male × ORFS male adapter, Parker’s F5OLO.
- NPT or BSPP port: Parker makes straight adapters from both to JIC and to ORFS. The adapter finder names them by size.
Know your port and hose end?
Find the adapterWhich one is better?
Each is built for its own job, and a machine uses whatever its maker chose. An O-ring seal is the preferred choice for high-pressure applications, and ORFS fittings are becoming the most popular international type on global machines for their sealing and vibration resistance. When you replace a part, match what’s there.
Before you loosen a fitting
- Turn the machine off, put the equipment in a safe, neutral position and release the pressure before you loosen anything. Turning off the pump may not release it: check valves can hold pressure in a hose, and it can take minutes or hours to bleed away.
- Never feel for a leak with your hand or any other part of your body. Oil under pressure can go through skin, and a pinhole leak can be almost invisible.
- If oil gets under your skin, get medical help at once, even if it doesn’t hurt. An injection injury can lead to amputation.
- Threads that screw together don’t prove the parts match. Some parts that don’t belong together still thread on, and then leak or come apart under pressure.
- Use only fittings whose published working pressure is at or above your machine’s maximum pressure. If a fitting has no published rating, don’t use it.
- Stay clear the first time you run the machine under pressure after a repair.