ORFS fittings – leak-free tube and hose connections for hydraulics

ORFS (O-Ring Face Seal) is the industry standard for leak-free hydraulic connections at high pressure and with vibration. With an elastomer o-ring in the sealing face, ORFS creates a reliable seal that can be reassembled and that minimises downtime, spillage and re-tightening.

What is an ORFS fitting, and how does it work?

ORFS (SAE J1453) uses a flat sealing face (“flat face”) with an o-ring that is compressed against a mating face when the fitting is assembled. Unlike metal-to-metal cone solutions, you get:

A stable seal under pulsating high pressure.
Resistance to vibration and over-tightening.
“Zero clearance” – lateral removal/installation without bending/cutting tubes.
Re-usable seal: the o-ring and flat face allow repeated disassembly/assembly.

Standard and thread types

Standard: SAE J1453 (ORFS).
Typical thread: UN/UNF (straight), used with a flat sealing face and o-ring.
Sizes: typically -4 to -24 (1/4”–1 1/2”) – see product data for details.

Benefits of ORFS for demanding applications

Leak-free operation: the o-ring compensates for tolerances and vibration.
Fast servicing: zero clearance makes maintenance easier in tight installations.
Safety and cleanliness: less oil spillage, a better working environment.
Low total cost: less re-tightening and fewer stoppages.

Trap-Seal – holds the o-ring in place and prevents assembly errors

Parker’s Trap-Seal technology retains the o-ring in a trapezoidal groove, so that it:

Does not fall out during storage handling or assembly.
Is not pinched/cut during assembly.

The result is greater assembly reliability and fewer leaks.

Corrosion resistance with ToughShield

In harsh environments, corrosion is a frequent cause of leaks and seized fittings. Parker O-Lok is supplied with ToughShield plating, documented for up to 1000 hours of corrosion resistance in tests – 10× the SAE requirement. This extends service life and service intervals. Read more about ToughShield here.

Variants and extended temperature/media requirements

Seal-Lok for CNG: special elastomer with improved ozone resistance and a wide temperature range (-40 °F to 300 °F) for natural gas applications.
Seal-Lok Xtreme: patented metallic seal for extreme chemistry and temperatures (-328 °F to 1200 °F).

Typical applications

Mobile and stationary hydraulic systems (construction/civil engineering, agriculture, materials handling).
Offshore, marine and heavy industry with vibration and corrosive environments.
Energy and process industry, incl. CNG and other gas applications.

ORFS products at Hymatik

ORFS tube fittings (Seal-Lok): elbow, tee and straight fittings in many sizes and configurations. Buy ORFS tube fittings.
ORFS hose fittings: for crimping onto hydraulic hoses for leak-free hose assemblies. Buy ORFS hose fittings.

Why choose Hymatik?

100,000+ item numbers in stock and fast delivery.
A wide range of Parker Seal-Lok ORFS, incl. Trap-Seal and ToughShield.
If you have any questions, call 63 12 83 00.

Frequently asked questions about ORFS fittings (FAQ)

What is the difference between ORFS and JIC? ORFS uses an o-ring in the sealing face for an elastomer seal, whereas JIC is metal-to-metal (37° cone). ORFS is typically better with vibration and for repeated disassembly/assembly.

Can I reuse ORFS connections? Yes, ORFS can normally be reassembled. Inspect and replace the o-ring in case of wear/damage, and follow the torque chart when assembling.

Which media and temperatures can ORFS handle? Standard ORFS covers typical hydraulic oils and operating temperatures depending on the o-ring material. For extended requirements, Seal-Lok CNG (-40 °F to 300 °F) and Seal-Lok Xtreme (-328 °F to 1200 °F) are available.

How do I avoid leaks during assembly? Ensure cleanliness, the correct o-ring and the right torque, and avoid over-tightening. Trap-Seal reduces the risk of o-ring failure

ORSF tube fittings ORFS hose fittings