37° Flare (JIC) Union Fitting: Tube-to-Tube Connector

Create a reliable, serviceable connection between two tube ends. The Stark 37° Flare (JIC) Union is engineered in compliance with SAE J514 and ISO 8434-2 standards, providing a globally recognized solution for joining two flared tubes. Its simple yet robust design creates a highly reliable metal-to-metal seal on the 37° flared surfaces, making it the industry standard for high-vibration and high-pressure applications in mobile hydraulics, industrial machinery, and heavy equipment.

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✓ SAE J514 / ISO 8434-2 Compliant| ✓ Proven Metal-to-Metal Seal| ✓ Extreme Vibration Resistance

🔧 Configure Your JIC Union in Seconds

Find your required fitting by selecting the tube O.D. and system type.

1. Select Your System:○ Imperial (Fractional) ○ Metric

🔥 Most Popular Sizes (In Stock - Same Day Shipping)

1/4"	3/8"	1/2"	3/4"
SS-JU-AN4	SS-JU-AN6	SS-JU-AN8	SS-JU-AN12
[Add to Quote]	[Add to Quote]	[Add to Quote]	[Add to Quote]

Part Number Format: [Material]-JU-[Tube Size] (e.g., INC625-JU-AN4)

(JU = JIC Union)

🛠 The Engineering Advantage

Reliable Metal-to-Metal Seal: The 37° flared tube ends form a perfect seal against the 37° cones inside the fitting. This simple, line-contact metal seal is highly effective, easy to inspect, and less susceptible to failure from chemical attack or extreme temperatures compared to elastomeric seals.

Superior Vibration Resistance: The design of a JIC connection provides excellent resistance to loosening under heavy vibration, making it the go-to choice for demanding applications like construction equipment, agricultural machinery, and industrial power units.

Global Standard Compliance (SAE J514): Our fittings are manufactured to the strict dimensional tolerances of SAE J514 / ISO 8434-2. This guarantees full interchangeability with other compliant JIC fittings from major brands like Parker® and Swagelok®, simplifying your MRO and global sourcing.

Forged Body for High-Pressure Integrity: Machined from one-piece forged 316/316L stainless steel, our connectors offer superior strength and fatigue resistance to handle the high pressures and pressure spikes inherent in hydraulic systems.

📈 Technical Specifications

Feature	Stark Standard Specification
Standard	SAE J514 / ISO 8434-2
Body Material	Forged 316/316L Stainless Steel
Pressure Rating	Up to 5000 PSI (345 bar) or higher, per SAE J514
Sealing Method	37° Metal-to-Metal Cone Seal
Compliance	MTR to EN 10204 3.1 & PMI Verified

🎯 Why Choose JIC? A Technology Comparison

Feature	Welded Connection	Compression Fittings (Ferrule)	37° Flare (JIC)
Installation	⚠️ Requires hot work, skilled labor	✅ Cold installation, simple	✅ Cold installation, simple
Vibration Resistance	Good	Good	Excellent
Reusability	❌ None	Excellent	Good
Inspection	⚠️ Requires NDT (X-ray, etc.)	Visual	✅ Easy Visual Inspection

📌 Targeted Application Support

Mobile Hydraulics: The industry standard for joining long runs of hydraulic lines on construction, agricultural, and forestry equipment.

Industrial Power Units: Provides robust, serviceable connections for pumps, valves, and cylinders in factory hydraulic systems.

Fuel & Fluid Transfer: A reliable choice for fuel lines, lubrication systems, and other industrial fluid transfer applications.

System Repair & Maintenance: Allows for easy replacement of damaged tube sections without replacing the entire line.

❓ Frequently Asked Questions (FAQ)

Q1: What does "JIC" stand for?

JIC stands for "Joint Industry Council," which originally created the standard. It is now formally known as the SAE J514 standard. The term "JIC" is still widely used in the industry to refer to any 37° flare fitting.

Q2: Do I need to use thread sealant or PTFE tape on JIC threads?

No. This is a critical point. The seal in a JIC connection happens on the 37° flared surfaces, not on the threads. The threads are only there to provide the mechanical force to press the two flared surfaces together. Using sealant on the threads can actually introduce contaminants into the system.

Q3: What is the difference between a JIC (37°) and an SAE (45°) flare fitting?

They are not interchangeable. JIC fittings have a 37° flare angle and are used for high-pressure hydraulic systems. SAE 45° flare fittings are typically used for lower pressure applications like automotive fuel and brake lines. Mixing them will result in a dangerous leak.

Q4: Are your JIC fittings interchangeable with Parker Triple-Lok® or Swagelok AN®?

Yes. Our 37° Flare fittings are manufactured in strict accordance with the SAE J514 standard, making them fully dimensionally and functionally interchangeable with other compliant fittings, including Parker's Triple-Lok® series and Swagelok's AN® fittings.

📦 Complete Size Chart

Need a custom material or thread type?[Request Custom Configuration]

💬 Still Have Questions?

Our engineering team is ready to assist with technical selection, system design, or material recommendations.

[Chat with an Engineer] [Email: sales@starkvalve.com] [Call: +86-13917221881]

🔒 Disclaimer

Swagelok AN® and Parker Triple-Lok® are registered trademarks of their respective holders. Stark is not affiliated with, endorsed by, or sponsored by these companies. Part numbers and brand names are provided for cross-reference and compatibility purposes only.