DELPHI FITTINGS
Product Overview
The Delphi Fittings Part FS306 is an SAE O-Ring Face Seal (ORFS) Bulkhead Locknut. This essential component is specifically designed to secure male ORFS bulkhead style fittings (such as the FS2700, FS2701, FS2702, FS2703, and FS2704 series) to a panel, bulkhead, or equipment wall. The locknut threads onto the body of the male ORFS bulkhead fitting on the opposite side of the panel, providing the necessary clamping force to hold the fitting firmly in place and ensure a stable pass-through for hydraulic lines. Manufactured from high-quality carbon steel and zinc-plated for corrosion resistance, the FS306 locknut is an indispensable part of any ORFS bulkhead installation, conforming to relevant dimensional aspects of SAE J1453 / ISO 8434-3 standards for thread and hex size compatibility.
Key Features & Specifications
| Material | High-Grade Carbon Steel |
|---|---|
| Thread Type | Female UNF/UN (Unified National Fine/Unified National) straight threads, dimensioned to match the corresponding male ORFS bulkhead fitting body threads (per SAE J1453 / ISO 8434-3). |
| Design | Hexagonal locknut, typically manufactured with a profile suitable for bulkhead applications (may be thinner than standard service nuts but robust enough for securing). |
| Body Style | Hex nut for secure tightening with a standard wrench. |
| Compatibility | Specifically designed for use with SAE ORFS male bulkhead fittings (e.g., Delphi FS2700, FS2701, FS2702, FS2703, FS2704 series and similar). |
| Sealing Mechanism | This locknut primarily provides mechanical securing of the bulkhead fitting to the panel. It does not directly participate in the fluid seal, which is achieved by the O-ring on the male ORFS fitting ends. An additional flat washer or sealant may be used by the installer between the fitting shoulder/locknut and the panel if specific environmental sealing at the panel interface is required. |
| Primary Function | To securely fasten an SAE ORFS bulkhead fitting to a panel, bulkhead, or wall, preventing movement and ensuring a stable connection point for ORFS hydraulic lines. |
| Standard | Conforms to relevant dimensional aspects of SAE J1453 / ISO 8434-3 for thread and hex size compatibility with ORFS bulkhead fittings. |
| Plating & Finish | Cr3+ Trivalent Zinc Clear (ASTM B117 salt spray tested) |
| Reference Standard | SAE J1453 / ISO 8434-3 (O-Ring Face Seal Standard) |
Commonly Available Sizes (Part #FS306 Series)
Delphi Fittings manufactures standard and custom dash sizes for Part FS306. Engineering specifications, dimensions, and thread/flange sizes are detailed below:
| Delphi Part # | Size / Nominal Dimension | Standard Specification | Configuration |
|---|---|---|---|
| FS306-04 | For -04 (9/16-18 UNF Thread) ORFS Bulkhead Fittings | SAE Standard | Standard Production |
| FS306-06 | For -06 (11/16-16 UNF Thread) ORFS Bulkhead Fittings | SAE Standard | Standard Production |
| FS306-08 | For -08 (13/16-16 UNF Thread) ORFS Bulkhead Fittings | SAE Standard | Standard Production |
| FS306-10 | For -10 (1-14 UNS Thread) ORFS Bulkhead Fittings | SAE Standard | Standard Production |
| FS306-12 | For -12 (1-3/16-12 UN Thread) ORFS Bulkhead Fittings | SAE Standard | Standard Production |
| FS306-16 | For -16 (1-7/16-12 UN Thread) ORFS Bulkhead Fittings | SAE Standard | Standard Production |
| FS306-20 | For -20 (1-11/16-12 UN Thread) ORFS Bulkhead Fittings | SAE Standard | Standard Production |
| FS306-24 | For -24 (2-12 UN Thread) ORFS Bulkhead Fittings | SAE Standard | Standard Production |
Need non-standard dash sizes, custom flange drops, special port configurations, or alternative material grades (AISI 316 Stainless / Brass)? Delphi manufactures custom components to client blueprints.
Specific Applications & Hydraulic Circuit Routing
Part FS306 fittings provide reliable fluid power conveyance in demanding mobile and stationary equipment circuits:
- High-Vibration Mobile Equipment: Excavator booms, mining equipment, and hydrostatic drives where Part FS306 prevents hydraulic weeping under intense shock loads.
- Zero-Clearance Manifold Assembly: Flat face design allows slip-in component replacement without springing or spreading rigid hydraulic tubes.
- Extreme Pressure Impulse Circuits: Elastomeric face seal remains 100% leak-free throughout repetitive thermal cycles and impulse spikes.
Installation & Assembly Guidance
- O-Ring Retention Inspection: Inspect the machined face groove to ensure the O-ring is properly seated and retained prior to mating.
- Face-to-Face Alignment: Bring the flat faces into parallel contact before hand-threading the swivel nut to avoid pinching the O-ring.
- Calibrated Torque Tightening: Tighten the nut to the specified SAE J1453 torque value using a calibrated torque wrench.
- Dual-Wrench Counter-Torque: Always hold the fitting body hex with a backup wrench while torquing the connection to prevent twisting.
Why Source Part FS306 from Delphi Fittings?
- Strict Dimensional Precision: CNC machined to exacting tolerances for 100% interchangeability with North American and international systems.
- ASTM B117 Salt Spray Corrosion Protection: Electroplated with eco-friendly Cr3+ trivalent zinc clear for extended service life in harsh operating environments.
- 100% Thread & Seal Inspection: Every production batch undergoes strict optical and mechanical gauge inspection before packaging.
- Factory-Direct OEM Supply: Direct manufacturer pricing, full mill test reports (MTR), and ISO 9001:2015 quality assurance from Yuhuan, China.
Get a Quote for Part FS306 - SAE ORFS Bulkhead Locknut
Direct OEM container-load and distributor replenishment pricing, complete material test reports (MTR), and inspection samples available upon inquiry. Connect with our engineering sales team for rapid quotations and delivery schedules.
Complementary & Mating Hydraulic Fittings
Commonly paired with Part FS306 in hydraulic valve manifolds, power units, and industrial fluid power circuits:
