DELPHI FITTINGS
Part Number: FS318
SAE ORFS Braze Nut
Product Overview
The Delphi Fittings Part FS318 is an SAE O-Ring Face Seal (ORFS) Braze Nut. This female swivel nut is a critical component for creating a permanent ORFS connection directly onto a hydraulic tube. It is designed to be used in conjunction with an ORFS Braze Sleeve (such as Delphi Part FS319 or FS319W), which is brazed or welded onto the end of a tube to form the necessary flat sealing face. The FS318 nut then slides over the prepared tube and sleeve assembly, allowing it to be connected to a male ORFS fitting. This method provides a very robust and reliable ORFS tube end termination. Manufactured from high-quality carbon steel and typically zinc-plated for corrosion resistance, the FS318 braze nut conforms to the dimensional requirements of SAE J1453 / ISO 8434-3 for ORFS connections.
Key Features & Specifications
| Material | High-Grade Carbon Steel (suitable for brazing/welding) |
|---|---|
| Configuration | Female SAE O-Ring Face Seal (ORFS) Swivel Nut (threads conforming to SAE J1453 / ISO 8434-3) |
| Design | Swivel nut specifically designed to be used with a brazed/welded ORFS tube sleeve (e.g., FS319) to form a complete female ORFS connection on a tube end. |
| Body Style | Hexagonal nut for secure wrench tightening. |
| Compatibility | Must be used with an appropriate SAE ORFS Braze Sleeve (e.g., FS319, FS319W) of the corresponding size, which is then brazed/welded onto the tube end. The assembly then mates with a male ORFS fitting. |
| Sealing Mechanism | When assembled with a brazed sleeve on a tube, the flat face of the sleeve (with the O-ring from the mating male fitting) seals against the flat face inside the FS318 swivel nut, creating the ORFS connection. |
| Corrosion Protection | Standard Zinc Plating for enhanced durability and resistance to environmental corrosion. |
| Primary Function | To provide the female swivel nut component for creating a permanent, brazed/welded ORFS connection on the end of a hydraulic tube, allowing it to connect to a male ORFS fitting. |
| Working Pressure | Designed for high-pressure hydraulic systems. The ultimate pressure rating of the assembly will depend on the quality of the braze/weld, the tube material, and the mating ORFS fitting. |
Commonly Available Sizes (Part #FS318 Series)
Delphi Fittings offers the FS318 SAE ORFS Braze Nut in a comprehensive range of sizes, corresponding to standard hydraulic tube outer diameters and ORFS fitting sizes.
Examples include (ORFS Braze Nut Size for corresponding Tube OD and Male ORFS Fitting):
- FS318-04: For 1/4" Tube OD (mates with -04 Male ORFS, 9/16-18 UNF Thread)
- FS318-06: For 3/8" Tube OD (mates with -06 Male ORFS, 11/16-16 UNF Thread)
- FS318-08: For 1/2" Tube OD (mates with -08 Male ORFS, 13/16-16 UNF Thread)
- FS318-10: For 5/8" Tube OD (mates with -10 Male ORFS, 1-14 UNS Thread)
- FS318-12: For 3/4" Tube OD (mates with -12 Male ORFS, 1-3/16-12 UN Thread)
- FS318-16: For 1" Tube OD (mates with -16 Male ORFS, 1-7/16-12 UN Thread)
Note: This nut must be used with the corresponding SAE ORFS Braze Sleeve (e.g., Part FS319 or FS319W). For unlisted sizes, specific material requirements, or other custom needs, please contact our sales team.
Applications
The Part FS318 SAE ORFS Braze Nut, when used with its mating sleeve, is essential for:
- Creating permanent, high-integrity ORFS connections directly onto hydraulic tubing, eliminating the need for separate tube end adapters in some cases.
- Fabricating custom hydraulic tube assemblies where ORFS connections are specified for their superior leak resistance and performance in high-vibration or high-pressure environments.
- Use in industries such as mobile equipment manufacturing, industrial machinery, shipbuilding, and any application requiring robust, brazed/welded ORFS tube terminations.
- OEM applications where fixed ORFS tube ends are integrated into hydraulic system designs.
Installation & Usage Guidelines
- Ensure the hydraulic tube end is cut squarely, deburred, and perfectly clean.
- Slide the FS318 Braze Nut onto the tube with the threads facing away from the tube end.
- Position the appropriate FS319 (or FS319W) Braze Sleeve onto the tube end. The sleeve must be correctly oriented and bottomed out on the tube.
- The sleeve must then be securely brazed or welded to the tube according to industry best practices and appropriate procedures for the tube and sleeve materials. This process creates the flat sealing face required for the ORFS connection. Ensure the brazing/welding process does not damage the nut threads or the critical sealing face of the sleeve.
- After cooling and cleaning, the FS318 nut can be brought forward over the brazed sleeve.
- The assembly is now ready to connect to a male ORFS fitting. Ensure the O-ring on the male ORFS fitting is clean, lubricated, and correctly seated.
- Align the prepared tube end (with nut and brazed sleeve) with the male ORFS fitting. Hand-tighten the FS318 swivel nut onto the male fitting until the flat faces make contact.
- Use appropriate wrenches to tighten the FS318 nut to the manufacturer's recommended torque for the specific ORFS size.
Why Choose Delphi Fittings Part FS318?
- Enables Permanent ORFS Tube Ends: Allows for the creation of highly reliable, brazed/welded ORFS connections directly on hydraulic tubes.
- Superior Leak Prevention (as part of assembly): When correctly assembled with a brazed sleeve and mated to an ORFS male fitting, it contributes to the exceptional sealing performance of the ORFS system.
- Robust and Durable: Designed for high-pressure hydraulic applications, providing a strong and lasting connection point.
- Standard Compliance: Threads and critical dimensions conform to SAE J1453 / ISO 8434-3 for ORFS connections.
- High-Quality Material: Manufactured from high-grade carbon steel suitable for brazing/welding operations.
- Enhanced Corrosion Resistance: Standard zinc plating provides good protection against environmental factors.
- Quality-Assured Manufacturing: Produced under Delphi Fittings' rigorous ISO 9001:2015 certified quality management system.
Get a Quote for Part FS318 - SAE ORFS Braze Nut
For creating robust, permanent ORFS connections on hydraulic tubing when used with a corresponding braze sleeve, the Part FS318 Braze Nut is an essential component. Contact Delphi Fittings today for wholesale pricing, bulk order information, and expert technical support.
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