What is SAE 45° Flare Thread (SAE J512)

SAE 45° Flare threads are another type of fitting used in hydraulic and fluid transfer systems, often alongside JIC 37° Flare. Here’s a breakdown of their key characteristics and differences:

SAE 45° Flare:

• Angle:As the name suggests, the flared tube features a 45-degree angle, slightly steeper than JIC’s 37 degrees.
• Seal:Similar to JIC, SAE 45° Flare relies on a metal-to-metal seal between the flared tube and the fitting seat for leak-proof connection.
• Thread Standard:It follows the SAE J512 standard for thread specifications, which are distinct from JIC’s.
• Compatibility:While not directly interchangeable with JIC 37° Flare due to differing thread standards, some sizes and configurations might allow cross-connection with additional adapters or modifications.
• Applications:Commonly used in various hydraulic and fluid transfer systems, including refrigeration, fuel lines, air conditioning units, and instrumentation lines.
• Advantages:
  • Leak-proof and reliable seal under high pressure.
  • Reusable with proper care and maintenance.
  • Available in a variety of sizes and configurations.
• Disadvantages:
  • Requires specific tools for installation and removal like a 45° flare nut wrench.
  • Not directly interchangeable with JIC 37° Flare without adapters.

Comparison with JIC 37° Flare:

SAE 45° Flare threads are widely found in low pressure applications like refrigerant and fuel lines, as well as automotive piping applications. Both halves have a 45° flare seat, and the threads of the each connector engage together to form a tight mechanical connection, with the seal forming on the 45° flare seat. Usually this thread is not used in hydraulic quick couplings, but some customers need to customize this type of thread for natural gas supply.