Hydraulic Fitting Types: Global Identification Guide
We stock, identify, crimp, and install every major hydraulic fitting type used globally — American JIC & ORFS, European DIN Metric & BSP, British BSPT, Japanese Komatsu 30°, high-pressure SAE flanges, and all common adapters.
Quick answer: the fastest way to identify a hydraulic fitting is by seal type, not just thread size. Metal-to-metal flare cones (JIC 37°, JIS 30°, SAE 45°) seal on the angle itself; flat-face fittings (ORFS) seal on an O-ring; tapered threads (NPT, BSPT) seal by thread interference; and straight threads (BSPP, ORB) seal with a washer or boss O-ring. Match seal type first, thread size second — full comparison chart below.
Hydraulic Fitting Types at a Glance
Hydraulic fittings vary by region, equipment brand, pressure rating, and sealing method. We carry and understand all major global standards, so you get the correct fitting or adapter the first time.
| Fitting type | Seal method | Thread angle | Common region / brands | Typical use |
|---|---|---|---|---|
| NPT / NPTF | Tapered thread interference | 60° | North America, general industrial | General-purpose, low-to-mid pressure |
| JIC 37° Flare | Metal-to-metal flared cone | 37° | North America; Caterpillar, John Deere, Case | High-pressure hose connections |
| ORFS | Flat face + O-ring | N/A (flat face) | North America / growing global adoption | High vibration, pressure impulse |
| ORB | Straight thread + boss O-ring | N/A (straight) | North America, pumps & manifolds | High-pressure port connections |
| Banjo | Crush washer, hollow bolt | N/A (swivel) | Global, brake & tight-clearance lines | Low-to-mid pressure, needs to pivot |
| SAE Code 61 / 62 Flange | Bolted flange + O-ring | N/A (flat flange) | Global, large-diameter high pressure | Up to 6,000+ psi, large hose sizes |
| SAE 45° Flare | Metal-to-metal flared cone | 45° | Automotive, refrigeration, brass lines | Fuel lines, air brakes, low pressure |
| DIN Metric 24° Cone | Bite-type sleeve or O-ring | 24° | Europe; Volvo, Liebherr | General industrial fluid systems |
| BSPP (G thread) | Bonded washer or O-ring | N/A (parallel) | Older European industrial equipment | Low-to-mid pressure |
| BSPT (R thread) | Tapered thread interference | 55° | Older European equipment | General industrial, non-NPT interchange |
| Metric 60° Cone | Recessed cone, straight thread | 60° | European trucks, specialty lines | Low-to-mid pressure fluid routing |
| JIS 30° / Komatsu Flare | Flared cone, metric/BSP threads | 30° | Komatsu, Hitachi, Kobelco, Kubota | Asian heavy machinery fleets |
North American & SAE Hydraulic Fittings
Most common in the United States, Canada, and on American & global OEM equipment (Caterpillar, John Deere, Case, etc.).
NPT / NPTF — National Pipe Taper / Dryseal
Tapered pipe threads at a 60° angle. NPTF is the dry-seal version engineered to form a mechanical seal without fluid leaks — the most commonly requested fitting type in general industrial hydraulics.
- Very common in general industrial hydraulics
- Standard NPT often needs thread sealant or Teflon tape
JIC 37° Flare (SAE J514)
37° flared cone, metal-to-metal contact seal — the standard high-pressure hose fitting design in North America.
- Highly reusable and very common on high-pressure hoses
- Strong resistance to system vibration
ORFS — O-Ring Face Seal (SAE J1453)
Flat face matched against an integrated O-ring groove — the modern leak-free standard for fluid systems.
- Best for high vibration and severe pressure impulse
- Growing adoption among major global manufacturers
ORB — O-Ring Boss (SAE J1926 / ISO 11926)
Straight UNF threads with a rubber O-ring seal nested inside a machined port or boss entry.
- Excellent for high-pressure connections into manifolds and pumps
- Resists thread-stripping compared to over-tightened tapers
Banjo Fittings
A hollow bolt passes through a rotating “banjo” eye fitting, sealed by crush washers on either side, letting the hose swivel without twisting the line.
- Common on brake lines and low-to-medium pressure circuits
- Ideal for tight-clearance mounting points
SAE Code 61 & Code 62 4-Bolt Flange (SAE J518)
High-pressure bolt-down flange for larger hose diameters and pressures up to 6,000+ psi, once threaded connections aren’t practical.
- Code 61: standard high-pressure applications
- Code 62: thicker flange, larger bolts, extreme duty
SAE 45° Flare
An older 45° flare style, mostly localized to automotive lines, refrigeration, and low-pressure brass configurations.
- Not interchangeable with JIC 37° threads
- Common on fuel lines, air brakes, light utility equipment
European & Metric Hydraulic Fittings
Standard on European, Asian, and international machinery (Volvo, Liebherr, Komatsu, Hitachi, etc.).
DIN Metric 24° Cone (DIN 2353 / ISO 8434-1)
The most widely used metric DIN fitting type on industrial fluid systems worldwide.
- Available in Light (L series) & Heavy (S series)
- Bite-type sleeve or elastomeric O-ring seal
BSPP — British Standard Pipe Parallel (G thread / ISO 228)
Parallel straight threads that rely on a bonded sealing washer (Dowty seal) or embedded O-ring to contain pressure.
- Extremely common on older European industrial equipment
- Thread pitches follow British Standard Whitworth dimensions
BSPT — British Standard Pipe Tapered (R thread / ISO 7)
Tapered threads at a 55° angle. Visually similar to NPT, but non-interchangeable due to pitch variance.
- Seals via thread interference and mechanical deformation
- Needs quality thread paste or wrap for a reliable seal
Metric 60° Cone (DIN 7631)
A 60° internal recessed cone matched to straight metric threads, for straightforward sealing on specialized lines.
- Common on specialized adaptations and European trucks
- Dependable for low-to-medium pressure routing
Japanese & Asian Hydraulic Fittings
Common on Komatsu, Hitachi, Kobelco, Kubota, Takeuchi, and other Asian-built machines.
JIS 30° Flare / Komatsu 30° Flare
A 30° flare-angle seat using metric or BSP parallel threads, built for fast deployment across Asian heavy machinery fleets.
- Reliable sealing under demanding construction use
- Protects connections from sudden pressure surges
For more detailed technical guidelines on fluid system connections and structural pressure specifications, you can consult official safety outlines documented by the international International Organization for Standardization (ISO). If you’re tracking down emergency local fabrication or system parts on a deadline, see our Flexible Hose & Fittings Solutions page.
Hydraulic Fitting Identification: FAQ
What’s the difference between JIC 37° and BSPT fittings?
JIC 37° fittings seal with a 37-degree flared cone against metal-to-metal contact and use UN/UNF straight threads. BSPT fittings seal by tapered thread interference at a 55-degree thread angle. They look similar but the threads are not interchangeable — forcing them together will damage both fittings.
How can I tell NPT and BSPT fittings apart without a thread gauge?
NPT uses a 60-degree thread angle and is common on North American equipment; BSPT uses a 55-degree thread angle and is common on older European equipment. Without a gauge, thread the suspect fitting into a known NPT female port by hand — BSPT threads will feel loose or bind unevenly because the pitch doesn’t match.
When do I need an SAE Code 61 or Code 62 flange instead of a threaded fitting?
Once hose diameter or system pressure exceeds what a threaded connection can reliably seal, a bolted 4-hole flange is used instead. Code 61 is rated for standard high-pressure service; Code 62 uses a thicker head and larger bolts for higher-pressure, larger-diameter lines.
Are ORFS fittings interchangeable with JIC 37° fittings?
No. ORFS seals with a flat face against an O-ring groove, while JIC seals with a 37-degree flared metal-to-metal cone. The thread sizes can sometimes match, but mixing the two seal types will leak under pressure — always match seal type, not just thread size.
What fitting type is standard on Komatsu and other Asian-built machinery?
Komatsu and many other Asian-built machines use a JIS 30° flare fitting, which seals at a 30-degree flare angle on metric or BSP parallel threads — a different flare angle than the 37-degree JIC standard used in North America.
We Stock & Crimp Every Major Fitting Type
NPT • NPTF • JIC 37° • ORFS • ORB • Banjo • SAE Code 61/62 Flange • BSPP • BSPT • DIN 24° Metric • JIS 30° • Komatsu fittings • Metric 60° Cone • Conversion adapters • Stainless steel & brass options
Wrong fitting = downtime. Call us — we’ll get you the right one fast.