What makes ORFS fittings the best choice for high-vibration systems?

The ORFS system utilizes a soft, elastomeric O-ring seal compressed between two flat metal faces. This design absorbs system vibration and shock, preventing the loosening and fluid leaks common with metal-to-metal seals like JIC.

What is the 'zero clearance' advantage of ORFS fittings?

Zero clearance means a component can be removed from a hydraulic line by pulling it straight out, without needing to bend or displace adjacent rigid tubes. This makes maintenance in tight spaces significantly faster and easier compared to tapered or flared fittings.

What is the difference between ORFS and ORB fittings?

ORFS (O-Ring Face Seal) is a line-to-line connection, ideal for joining hoses or tubes. ORB (O-Ring Boss) is a line-to-port connection, designed for sealing a fitting into a machined port on a pump, valve, or cylinder. Both use an O-ring but serve different functions.

Workbench view of forged steel O-Ring Face Seal (ORFS) hydraulic fittings, showing the critical flat sealing face and O-ring groove.

Steel O-Ring Face Seal (ORFS) Fittings (SAE J1453)

The Premier Zero-Leak Solution for High-Vibration Hydraulic Systems.

The Engineer's Choice for Absolute Reliability.

In equipment that runs hard all day, vibration is a constant enemy that compromises metal-to-metal seals like JIC. The O-Ring Face Seal (ORFS) system, compliant with the SAE J1453 standard, is the definitive engineering solution for achieving a zero-leak connection in high-vibration and high-pressure hydraulic systems.

The design is robust: a high-durometer O-ring is captured in a groove on the male fitting's flat face, which is then compressed against the flat face of the female fitting. This creates a soft, resilient seal with the structural strength of a forged steel body. For OEMs, it means fewer warranty claims. For distributors, it means stocking a premium, problem-solving product. Plus, its zero-clearance design allows for rapid component replacement in tight spaces, a powerful selling point for any maintenance-conscious customer. For applications requiring extreme corrosion resistance, see our 316 Stainless Steel ORFS line.

O-Ring Face Seal (ORFS) Fitting Catalog (Steel)

SAE ORFS Tube Union

Part #: FS2403

Connects two ORFS female swivel fittings or specially prepared tube ends in a straight line. Male ORFS flat face ends.

SAE ORFS Male x NPTF Pipe Male Adapter

Part #: FS2404

Straight adapter connecting a female ORFS swivel fitting to a female NPTF port. Male ORFS x Male NPTF ends.

SAE ORFS Swivel Nut Reducer / Expander

Part #: FS2406

Adapter allowing connection between different ORFS thread sizes. Features female swivel nuts on both ends.

SAE ORFS Plug

Part #: FS2408

Seals an unused female ORFS swivel fitting or port. Male ORFS flat face with O-ring groove.

SAE ORFS Swivel Nut Straight Adapter

Part #: FS7504

Straight connector typically with female ORFS swivel nuts on both ends for joining male ORFS fittings.

SAE ORFS Male 90° Elbow

Part #: FS2500

Changes flow direction by 90°. Connects two female ORFS swivel fittings. Male ORFS ends.

SAE ORFS Male x NPTF Pipe Male 90° Elbow

Part #: FS2501

90° adapter elbow connecting a female ORFS swivel fitting to a female NPTF port. Male ORFS x Male NPTF ends.

SAE ORFS Male x NPTF Pipe Male 45° Elbow

Part #: FS2503

45° adapter elbow connecting a female ORFS swivel fitting to a female NPTF port. Male ORFS x Male NPTF ends.

SAE ORFS Male x NPTF Pipe Male Branch Tee

Part #: FS2601

Tee adapter connecting one female ORFS swivel and two female NPTF ports. Male ORFS branch, Male NPTF run ends.

SAE ORFS Male Tee

Part #: FS2603

Connects three female ORFS swivel fittings in a tee configuration. All ends Male ORFS.

SAE ORFS Male Cross

Part #: FS2650

Connects four female ORFS swivel fittings at 90° angles. All ends Male ORFS.

SAE ORFS Male Bulkhead Union

Part #: FS2700

Connects two female ORFS swivel fittings through a panel or bulkhead. Straight union with locknut. Male ORFS ends.

SAE ORFS Male Bulkhead 90° Elbow

Part #: FS2701

90° elbow fitting designed to pass through a panel or bulkhead, connecting ORFS lines. Male ORFS ends, includes locknut.

SAE ORFS Male Bulkhead 45° Elbow

Part #: FS2702

45° elbow fitting for bulkhead pass-through, connecting ORFS lines. Male ORFS ends, includes locknut.

SAE ORFS Male Bulkhead Branch Tee

Part #: FS2703

Tee fitting where one connection passes through a bulkhead. Typically Male ORFS ends, includes locknut.

SAE ORFS Male Bulkhead Run Tee

Part #: FS2704

Tee fitting where the straight-through ('run') connection passes through a bulkhead. Male ORFS ends, includes locknut.

SAE ORFS Cap

Part #: FS304C

Seals the end of a male ORFS fitting. Female ORFS swivel nut with a flat sealing face.

SAE ORFS Bulkhead Locknut

Part #: FS306

Nut used to secure an ORFS bulkhead fitting (like FS2700 series) to a panel or bulkhead wall.

SAE ORFS Braze Nut

Part #: FS318

Female swivel nut designed to be brazed onto a tube end, used with sleeve FS319.

SAE ORFS Braze Sleeve (FS319 / FS319W)

Part #: FS319 / FS319W

Sleeve component designed to be brazed onto a tube end to create the flat sealing face for ORFS connections.

Tube Sleeve ORFS - Mechanical

Part #: FS319M

Mechanical sleeve, potentially for a flareless ORFS tube connection system (differs from braze type).

SAE ORFS Male x SAE ORB Male Straight Adapter

Part #: FS6400

Straight adapter connecting a female ORFS swivel fitting to an SAE O-Ring Boss port. Male ORFS x Male ORB ends.

ORFS Male x ORB Male Straight Adapter Long

SAE ORFS Male x SAE ORB Male Straight Adapter Long

Part #: FS6400L

Long version of the ORFS Male x ORB Male adapter for extended reach.

SAE ORFS Male x 37° Female JIC Swivel Adapter

Part #: FS6402

Straight adapter connecting a male JIC flare fitting/tube to an ORFS female swivel fitting. Male ORFS x Female JIC Swivel ends.

SAE ORFS Male x 37° Male JIC Adapter

Part #: FS6403

Straight adapter connecting a female ORFS swivel fitting to a female JIC swivel fitting/tube. Male ORFS x Male JIC ends.

ORFS Female Swivel x ORB Male Straight Adapter

SAE ORFS Female Swivel x SAE ORB Male Straight Adapter

Part #: FS6412

Straight adapter connecting a male ORFS fitting to an SAE O-Ring Boss port. Female ORFS Swivel x Male ORB ends.

SAE ORFS Male x ORFS Female Swivel 90° Elbow

Part #: FS6500

90° elbow with one male ORFS end and one female ORFS swivel nut end.

SAE ORFS Male x ORFS Female Swivel 45° Elbow

Part #: FS6502

45° elbow featuring one male ORFS end and one female ORFS swivel nut end.

ORFS Female Swivel x JIC Male Straight Adapter

SAE ORFS Female Swivel x 37° Male JIC Straight Adapter

Part #: FS6504

Straight adapter connecting a male ORFS fitting to a female JIC swivel/tube. Female ORFS Swivel x Male JIC ends.

SAE ORFS Swivel Nut Branch Tee

Part #: FS6600

Tee fitting where the branch connection uses a female ORFS swivel nut. Run ends typically male ORFS.

SAE ORFS Male x SAE ORB Male 90° Elbow

Part #: FS6801

90° adapter elbow connecting a female ORFS swivel fitting to an SAE O-Ring Boss port. Male ORFS x Male ORB ends.

SAE ORFS Male x SAE ORB Male 45° Elbow

Part #: FS6802

45° adapter elbow connecting a female ORFS swivel fitting to an SAE O-Ring Boss port. Male ORFS x Male ORB ends.

SAE ORFS Male x SAE ORB Male Branch Tee

Part #: FS6803

Tee adapter connecting one female ORFS swivel and two ORB ports. Male ORFS branch, Male ORB run ends.

SAE ORFS Male x SAE ORB Male Run Tee

Part #: FS6804

Tee adapter connecting one ORB port and two female ORFS swivel fittings. Male ORB branch, Male ORFS run ends.

SAE ORFS Female Swivel x SAE ORB Male 90° Elbow

Part #: FS6809

90° adapter elbow connecting a male ORFS fitting to an SAE O-Ring Boss port. Female ORFS Swivel x Male ORB ends.

SAE ORFS Swivel Nut Run Tee

Part #: FS6602

Tee fitting where the run connections use female ORFS swivel nuts. Branch typically male ORFS.

Related ORFS Accessories

Buna N O-Ring for SAE ORFS Fittings

Part #: OFS1 Series

Standard Buna-N (Nitrile) O-rings specifically sized for the face groove on male SAE ORFS fittings. Suitable for common hydraulic fluids.

Viton® O-Ring for SAE ORFS Fittings

Part #: OFS2 Series

Viton® (FKM) O-rings sized for ORFS fittings, offering enhanced chemical and temperature resistance compared to Buna-N.

Using ORFS with JIC, ORB, NPT and BSP Systems

ORFS rarely lives in a vacuum. In real machines, O-Ring Face Seal connections sit next to JIC tube lines, NPT pipe ports, ORB manifolds and sometimes BSP threads on imported equipment. The adapters above are designed to bridge those worlds without creating new leak paths.

ORFS to JIC: use parts like FS6402 and FS6403 together with our JIC 37° flare fittings when you need to tie ORFS hose assemblies into existing JIC tube runs.
ORFS to NPT/NPTF pipe threads: straight and elbow adapters such as FS2404, FS2501 and FS2503 let you land ORFS hoses on NPT/NPTF ports without over-tightening tapered threads.
ORFS to SAE ORB ports: use FS6400, FS6412 and the FS6800 series with our SAE ORB fittings to connect ORFS lines to pumps, valves and cylinder ports that use straight-thread O-ring bosses.
ORFS to BSPP/BSPT on imported equipment: verify whether the thread is parallel or tapered, then pair this ORFS range with our BSPP or BSPT adapters instead of forcing an NPT part into a British thread.
When corrosion is the limiting factor: mirror critical lines in our stainless steel ORFS fittings while keeping the rest of the system in forged carbon steel.

Engineer's Guide to the SAE J1453 ORFS System

O-Ring Face Seal is the top-tier technology for connecting fluid lines in demanding applications. Understanding its three core advantages is key to leveraging its full potential.

1. The Superior Seal: Soft Seal, Hard Body

Unlike flared fittings that rely on deforming metal, ORFS uses an elastomeric O-ring compressed between two precision-machined flat faces. This "soft seal" is incredibly resilient to system impulses, shock, and vibration, maintaining a leak-tight connection where rigid seals would fail.

2. The Maintenance Game-Changer: Zero Clearance

This is a critical advantage for technicians. Because the fitting separates by pulling straight apart (not unscrewing like a pipe thread), a hose or valve can be removed from a line without bending or stressing adjacent rigid tubes. In a cramped engine bay, this can turn a multi-hour job into a 15-minute fix.

3. High-Pressure, High-Reliability

The combination of a robust, forged steel body and a protected O-ring seal allows ORFS fittings to handle extremely high working pressures, making them the standard choice for modern construction, mining, and heavy industrial equipment.

Critical Installation Notes

Protect the Faces: The integrity of the seal depends on the two flat faces being perfectly clean and free of nicks or scratches. Handle and store these fittings with care.
Inspect and Lubricate the O-Ring: Always use a new, correctly sized O-ring for reassembly. A tiny cut or debris can cause a leak. Lubricate it with clean hydraulic fluid before installation.
Follow Torque Specifications: The straight threads are for clamping only. Tighten to the specified torque to achieve the correct O-ring compression without damaging the fitting.

O-Ring Face Seal (ORFS) - Frequently Asked Questions

What is an ORFS fitting?

An ORFS (O-Ring Face Seal) fitting creates a leak-proof seal by compressing an O-ring between two flat, machined faces. The straight threads are only for clamping, making it extremely resistant to vibration and system shock.

Is ORFS better than JIC for high-vibration hydraulics?

Yes, significantly. The soft, elastomeric seal of an ORFS fitting absorbs vibration that can cause a metal-to-metal JIC flare seal to loosen and leak over time. For equipment with constant vibration, ORFS is the superior engineering choice.

What is the difference between ORB and ORFS?

ORB (O-Ring Boss) is for sealing a fitting into a port (on a pump, valve, etc.). ORFS is for connecting two lines (hose to hose, or tube to hose). Both use an O-ring, but they are designed for different connection points in a hydraulic system.

Do ORFS threads create the seal?

No. This is a critical point. The straight threads on an ORFS fitting only provide the clamping force to hold the two flat faces together. The seal is created 100% by the compressed O-ring.

Which O-Ring should I choose: Buna-N or Viton?

For standard hydraulic oils and operating temperatures (-30°C to +100°C), Buna-N (NBR) is the cost-effective choice. For high temperatures (up to +200°C) or systems with aggressive chemicals or biodiesel, you must upgrade to Viton® (FKM).

What sizes are standard for ORFS fittings?

ORFS fittings are commonly available in sizes from -4 (1/4") to -24 (1-1/2"). The size corresponds to the tube or hose OD. You can find a complete list of available sizes in our catalog above.

Are ORFS fittings reusable?

Yes, the fitting bodies are highly reusable. However, it is a best practice to always replace the O-ring during reassembly to ensure a perfect seal. The flat metal faces should also be inspected for any damage.

Can ORFS connect to JIC, NPT, or ORB ports?

Yes, through the use of specific adapters. We manufacture a full range of transition fittings, such as our FS6403 (ORFS to JIC), FS2404 (ORFS to NPTF), and FS6400 (ORFS to ORB), to integrate ORFS technology into existing systems.

The Zero-Leak Solution for Your Toughest Jobs.

Give your customers the reliability of O-Ring Face Seal. As a direct manufacturer, we have the capacity for high-volume orders of forged steel ORFS fittings. For wholesale pricing and a supply chain you can actually count on, talk to our team.

Get a Wholesale Quote on ORFS Need it in Stainless Steel?