DELPHI FITTINGS
Brass SAE 45° Flare Fittings
The Go-To Brass Fitting for Low-Pressure Fuel, Air, and Refrigeration Lines.
Not for Hydraulics. Perfect for Everything Else.
Let's be clear: this isn't a high-pressure hydraulic fitting. The Brass SAE 45° Flare fitting, built to the SAE J512 standard, is the workhorse for lower-pressure jobs. Think automotive fuel lines, HVAC refrigerant lines, and LP gas connections. It's a simple, reliable metal-to-metal seal that's been trusted in the field for decades.
We machine these from solid brass because it’s the right material for the job—it resists corrosion from fuel and chemicals, it’s easy to machine for a perfect seal, and it’s cost-effective for volume applications. For distributors and OEMs serving the automotive, HVAC, and marine markets, this is a core inventory item. It just works.
Brass SAE 45° Flare Fitting Catalog
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Part #: B-41S
SAE Short Flare Nut
Short pattern brass nut used with appropriately flared tubing to connect to a male SAE 45° flare fitting.
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Part #: B-41
SAE Long Flare Nut
Standard/long pattern brass nut used with flared tubing to connect to a male SAE 45° flare fitting.
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Part #: B-42
SAE Male Flare Union
Straight brass union connecting two female SAE 45° flare nuts/tubes of the same size.
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Part #: B-48
SAE Male Flare x NPTF Male Adapter
Connects a female SAE 45° flare connection to a female NPTF port. Male SAE x Male NPTF ends.
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Part #: B-46
SAE Male Flare x NPTF Female Adapter
Connects a female SAE 45° flare connection to a male NPTF pipe or fitting.
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Part #: B-40P
SAE Male Flare Plug
Brass plug used to seal an unused female SAE 45° flare fitting or port.
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Part #: B-40C
SAE Flare Cap
Brass cap with a female nut used to seal the end of a male SAE 45° flare fitting.
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Part #: B-44
SAE Male Flare Union Tee
Brass tee that connects three female SAE 45° flare lines together.
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Part #: B-45
SAE x NPTF Branch Tee
Tee with two female NPTF ports on the run and one male SAE 45° flare on the branch.
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Part #: B-51
SAE x NPTF Run Tee
Tee with two female SAE 45° flare connections on the run and one female NPTF port on the branch.
The Playbook for Brass 45° Flare Fittings
The SAE 45° flare fitting is a straightforward design. It's governed by the SAE J512 standard, and its reliability comes down to a clean flare and the right application.
How It Works: A Simple Metal-on-Metal Seal
There's no magic here. You use a flaring tool to create a 45-degree cone on the end of a soft tube (like copper or brass). A flare nut, which you remembered to slide on *before* flaring, clamps that cone against a matching 45-degree seat in the fitting. The straight UNF threads on the nut just provide the muscle to clamp it down; they don't do any of the sealing. It’s a simple, effective mechanical seal.
Why Brass is the Right Call for These Jobs
We make these out of brass for a reason. It's not for high-pressure hydraulics, so you don't need the brute strength of steel. Brass gives you exactly what you need for these applications:
- Corrosion Resistance: It stands up to gasoline, oil, refrigerants, and water without rusting.
- Easy to Work With: Brass tubing is soft enough to get a perfect, crack-free flare every time with basic tools.
- Cost-Effective: It delivers the performance needed without the higher cost of stainless steel.
The Payoff: Why It's So Common
- It's Reusable: Unlike a compression fitting, you can take a flare fitting apart and put it back together multiple times without issue, as long as the sealing surfaces are clean.
- No Pipe Dope Needed: The seal is on the flare, not the threads. That means no risk of sealant getting into your fuel injectors or refrigeration system.
- Widely Available: It's a North American standard, easy to find and match.
The Trade-Offs: Here's the Straight Skinny
- It's a Low-Pressure Fitting: This is the big one. These are not for your 3000 PSI hydraulic systems. They are for fuel lines, air lines, and refrigerant systems, typically operating well below 500 PSI. Using them for high pressure is asking for a failure.
- The Flare is Everything: A bad flare—one that's cracked, off-center, or uneven—will leak. Period. The quality of the connection is entirely dependent on the quality of the flare.
- Not for High Vibration: While decent, a simple metal flare can be more prone to loosening under severe, constant vibration than a fitting that uses an O-ring (like ORB or ORFS).
Where You'll Find It
You'll see brass SAE 45° fittings on:
- Automotive: Fuel lines, transmission cooler lines, and older brake systems (often using a specific "double flare" for safety).
- HVAC/R: Connecting copper tubing for air conditioning and refrigeration units.
- Gas Lines: Low-pressure connections for LP and natural gas appliances.
- Marine: Fuel and water lines on boats.
Need a Reliable Source for Brass Fittings?
Our catalog covers the most common brass SAE 45° configurations. As a direct manufacturer, we provide competitive quotes for wholesale and blanket orders. Talk to us about stocking your inventory.
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