About

A flare fitting is a type of mechanical tube fitting used to connect metal tubing (most commonly copper, aluminum, or steel) by flaring the end of the tube outward and clamping it against a matching tapered seat.

Key features:

• Seal type: Metal-to-metal seal (no gasket required)

• Flare angle: Most commonly 45 (SAE flare) in HVAC, refrigeration, and automotive systems; 37 (AN/JIC flare) in hydraulic and aerospace applications

• Components: Flared tube end, flare nut, and fitting body with a conical seat

How it works:
The tube end is flared using a flaring tool. When the flare nut is tightened, the flared tube is pressed against the fittings tapered seat, creating a tight, leak-resistant seal.

Common applications:

• HVAC and refrigeration lines

• Automotive brake and fuel systems

• Gas and fluid transfer lines

• Hydraulic systems (with 37 flares)

Advantages:

• Strong, vibration-resistant connection

• Can be disassembled and reassembled

• Suitable for high pressure and temperature (depending on material)

Materials:

• Brass (most common)

• Stainless steel

• Steel