Match fittings
How to identify hydraulic hose fittings
Check thread diameter and pitch, then identify the actual sealing surface, angle, gender, and fitting shape.
Use five checks—not one guess
1GenderMale, female, swivel, or fixed
2ThreadMajor diameter and pitch
3SealCone, flat face, taper, O-ring, or flange
4ShapeStraight, 45°, 90°, or special
5SizeHose bore and connection size
Identification sequence
- Clean and inspect the end
Expose the thread and seal without scratching the sealing surface. Look for an O-ring, cone, flare, flat face, or tapered thread.
- Measure the thread
Use calipers for major diameter and a pitch gauge for thread pitch. Do not identify a family from diameter alone.
- Find where it seals
Threads may only pull the joint together. The fluid seal may be on a cone, flare, O-ring, flat face, or flange.
- Check angle and movement
Record fitting angle and whether the nut swivels. For two bent fittings, also record their relative clocking.
- Verify the mating port
Compare the fitting with the actual port or adapter. Similar-looking thread families are not automatically interchangeable.
Common families: what the mechanic should look for
| Family | Typical sealing clue | Do not confuse with |
|---|---|---|
| JIC | 37° flare seat | Other flare angles or metric threads |
| ORFS | Flat face with an O-ring | Flat faces without the same O-ring design |
| BSPP | Parallel thread; seal is normally elsewhere | BSPT |
| BSPT / NPT | Tapered thread family | Each other; angle and pitch differ |
| Metric 24° cone | 24° cone with family-specific sealing arrangement | Other metric cone systems |
| SAE flange | Flange head, clamp halves, and O-ring face | Different pressure series or flange dimensions |