Part Number: 6405-SS

SAE ORB Male x NPTF Pipe Female Adapter (Stainless Steel)

Product Overview

The Delphi Fittings Part 6405-SS is a straight adapter, meticulously crafted from high-quality stainless steel (typically Grade 316 SS), designed to facilitate a secure connection between a component with a male SAE O-Ring Boss (ORB) port and a female NPTF (National Pipe Taper Fuel / Dryseal) threaded pipe or fitting. This robust adapter features a male SAE O-Ring Boss thread complete with an O-ring groove on one end, and a female NPTF pipe thread on the other. The inherent properties of stainless steel provide superior corrosion resistance, making the 6405-SS adapter an excellent choice for demanding applications in marine environments, chemical processing plants, food and beverage facilities, or pharmaceutical industries where system purity, longevity, and resistance to aggressive media are crucial.

Key Features & Specifications

Material	High-Grade Stainless Steel (Typically 316 SS for optimal corrosion resistance)
End 1 Configuration	Male SAE O-Ring Boss (ORB) (conforming to SAE J1926-1 / ISO 11926-1)
End 2 Configuration	Female NPTF Pipe (Dryseal) (conforming to ANSI B1.20.3 / SAE J476)
Body Style	Straight Adapter with hexagonal (hex) body for secure wrench engagement during installation.
Sealing Mechanism	ORB End: Utilizes an elastomeric O-ring (Viton® recommended for stainless steel applications) which seals against the chamfered boss of the mating female ORB port, providing a highly reliable, leak-proof seal. NPTF End: Designed to seal with a mating male NPTF pipe fitting (Dryseal). If connecting to a standard NPT male fitting, the use of a compatible thread sealant is recommended for an optimal seal.
Corrosion Protection	Inherent to the stainless steel material; may also be passivated to further enhance surface integrity and corrosion resistance.
Primary Function	To provide a straight, leak-proof connection from a male SAE ORB port to a female NPTF pipe or fitting, offering the enhanced durability and superior corrosion resistance of stainless steel.
Working Pressure	Suitable for high-pressure hydraulic systems. Specific pressure ratings are dependent on the size of the adapter and the particular application conditions.
O-Ring Material (for ORB end)	Viton® (FKM) is strongly recommended for stainless steel fittings to ensure compatibility with a wide range of fluids and temperatures. O-ring is typically supplied with the fitting.

Commonly Available Sizes (Part #6405-SS Series)

Delphi Fittings offers the 6405-SS Stainless Steel ORB Male to NPTF Female Adapter in a variety of common size combinations. Sizes are generally denoted by ORB dash numbers (for the male ORB end) and NPTF nominal pipe sizes (for the female NPTF end).

Examples include (Male ORB x Female NPTF):

6405-04-02-SS: -04 (7/16-20 UNF) ORB Male x 1/8" NPTF Female
6405-04-04-SS: -04 (7/16-20 UNF) ORB Male x 1/4" NPTF Female
6405-06-04-SS: -06 (9/16-18 UNF) ORB Male x 1/4" NPTF Female
6405-06-06-SS: -06 (9/16-18 UNF) ORB Male x 3/8" NPTF Female
6405-08-08-SS: -08 (3/4-16 UNF) ORB Male x 1/2" NPTF Female
6405-10-08-SS: -10 (7/8-14 UNF) ORB Male x 1/2" NPTF Female
6405-12-12-SS: -12 (1-1/16-12 UNF) ORB Male x 3/4" NPTF Female
6405-16-16-SS: -16 (1-5/16-12 UNF) ORB Male x 1" NPTF Female

Note: Each ORB male end is supplied with an appropriate O-ring (Viton® recommended for stainless steel applications). For unlisted size combinations, specific material grade requirements (e.g., 316L), or other custom needs, please contact our sales team.

Applications

The Part 6405-SS Stainless Steel adapter is essential for:

Connecting components with male ORB ports (such as certain types of pumps, valves, filters, or manifolds) to pipes, hoses, or other fittings that are terminated with male NPTF threads, especially within systems demanding the corrosion resistance of stainless steel.
Interfacing stainless steel ORB-ported equipment with stainless steel NPTF piping systems to maintain material consistency and prevent issues like galvanic corrosion.
Use in challenging environments including marine and offshore installations, chemical processing facilities, food and beverage production lines, and pharmaceutical manufacturing, where resistance to aggressive substances, saltwater, or frequent cleaning protocols is critical.
Applications requiring high levels of system purity and where the inert nature of stainless steel is advantageous.

Installation & Usage Guidelines

Thoroughly clean all ORB threads, the O-ring groove on the adapter's male ORB end, the female NPTF threads on the adapter, and all mating surfaces (female ORB port and male NPTF fitting) to ensure they are free from any damage, debris, or contaminants.
Verify that the O-ring material (Viton® is recommended for stainless steel and demanding applications) is correct for the specific system fluid, temperature, and pressure. Ensure the O-ring is correctly lubricated with a system-compatible fluid or an appropriate O-ring lubricant.
Carefully install the lubricated O-ring onto the ORB male end of the 6405-SS adapter, ensuring it is properly and evenly seated in its groove without being twisted, cut, or pinched.
Thread the ORB male end of the adapter into the mating female ORB port by hand until the O-ring makes initial contact with the port's chamfer and the fitting shoulder seats. Then, using a wrench on the adapter's hex body, tighten the fitting to the manufacturer's recommended torque specification for that specific ORB size and stainless steel material.
For the female NPTF end of the adapter, thread a mating male NPTF pipe or fitting into it. It is highly recommended to apply a suitable thread sealant (such as PTFE tape or a liquid pipe sealant specifically formulated for use with stainless steel and compatible with the system fluid) to the male NPTF threads. This is particularly important if mating with standard NPT male threads or to ensure an optimal seal in high-pressure NPTF connections. Tighten to the recommended specification for the NPTF connection size.
Always use appropriate backup wrenches on the adapter's hex body and the mating components during the tightening process to prevent distortion or damage. When working with stainless steel fittings, using a thread lubricant or anti-seize compound (compatible with stainless steel) on both the ORB male threads and the mating male NPTF threads is crucial to prevent galling during assembly.

Why Choose Delphi Fittings Part 6405-SS?

Unmatched Corrosion Resistance: Manufactured from high-grade stainless steel (typically 316 SS), offering maximum durability and extended service life in harsh chemical, marine, or high-humidity environments.
Reliable Sealing Performance: Combines the proven high-integrity SAE O-Ring Boss (ORB) seal for the port connection with the robust NPTF tapered thread connection for pipes and fittings.
Designed for High Pressure: Engineered to withstand the demanding pressures commonly found in modern industrial and mobile hydraulic systems.
Extensive Chemical and Temperature Compatibility: Stainless steel construction provides a significantly broader range of compatibility with aggressive fluids and extreme operating temperatures compared to standard carbon steel alternatives.
Strict Adherence to Industry Standards: Fully meets SAE J1926 (for the ORB end) and ANSI B1.20.3/SAE J476 (for the NPTF end) specifications, ensuring correct fit, reliable function, and global interchangeability.
Quality-Assured Manufacturing: Produced under Delphi Fittings' rigorous ISO 9001:2015 certified quality management system, guaranteeing consistent high quality and dependable performance.

Get a Quote for Part 6405-SS - Stainless Steel SAE ORB Male x NPTF Pipe Female Adapter

For durable, corrosion-resistant, and leak-proof straight connections from male ORB ports to female NPTF pipe or fittings in your most challenging applications, the Part 6405-SS stainless steel adapter is an outstanding choice. Contact Delphi Fittings today for wholesale pricing, information on bulk orders, and expert engineering support.

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