Highest Standard Fittings for Orbital and Suborbital Launch, Testing, and Ground Support

SAE 37 KJ Ultraflare
banner render KJ

An enhanced version of the standard SAE 37° Flared tube fitting, Ultraflare® KJ tube fittings feature a PTFE back-up seal in the flared fitting nose cone. The seal is extruded of virgin PTFE® and machined to create an interference fit-in-the-groove, or trepan, in the fitting nose. This trepan is machined parallel to the fitting center line to eliminate the risk of twisting the Teflon® seal out of its seat during assembly. This seal provides more forgiveness in tubing surface imperfections, under flaring and torquing, and higher overall pressure ratings.

(note: Available only through defined Aerospace Industry Distributors

Quick Links

Click Here for Ultraflare® KJ tube fittings

How to Order

Download Ultraflare KJ Tube Fittings Catalog



  • Working Pressure: Vacuum to 9,900 psig
  • Temperature Rating: -100 to 450° F
  • Body Materials: Corrosion resistant stainless steel Class 316, Code K, per QQ-S-763
  • Seal Materials:
    • Straight thread O-Ring: Acrylonitrile-Butadiene (NBR) 90-durometer
    • Nose seals:  Tetrafluoroethylene resin (TFE) per MIL-R-8791
  • Sizes: 1/4 to 2 in.
  • End Connections: ORFS, NPT, BSP, and SAE


The SAE 37° Ultraflare® KJ tube fitting consists of three components to make a tubing assembly: body, nut, and sleeve. The SAE flared tube fitting relies on metal-to-metal contact between the finished surface of the fitting nose and the inside diameter of the flared tubing to make a seal. SSP takes great care in the manufacturing process to produce a flared nose surface that far exceeds published specifications. This high finish reduces the likelihood of leakage due to irregularities in the flared tubing. As the fitting nose and flared tubing are drawn together, they are supported by the fitting sleeve, which distributes the compressing load caused by the nut as it is threaded onto the fitting body during assembly.

Ultraflare® KJ tube fittings meet all of the requirements for flared tube fittings, including adjustable and swivel elbows, reducers, and tees suitable for use in accordance with KSC-SPEC-Z-0008.
UltraFlare® KJ fittings are designed to the requirements of KSC-GP-425 and AS1098


Stainless steel Ultraflare® KJ tube fittings are manufactured from Type 316 corrosion-resistant steel, condition A (code K), in accordance with QQ-S-763.


Ultraflare® KJ tube fitting is an extremely good choice in many cases for both new system design, and replacement of existing SAE flared tube fittings. For new system design, the Ultraflare® KJ tube fitting offers a superior alternative to a standard SAE Flared fitting through its improved resistance to vibration and sealing reliability. The Ultraflare® KJ tube fitting is also more forgiving of assembly irregularities in the shop or field, such as under flared tubing or under-torqued make-ups.

The Ultraflare® KJ tube fitting uses standard SAE nuts & sleeves, and is assembled following normal procedures and techniques for SAE flared tube fittings. As such, for companies with an investment in tube flaring equipment and training, the Ultraflare® KJ tube fitting represents a superior performing fitting system without the need for new capital equipment or technician training.

In the field, or for system maintenance, Ultraflare® KJ tube fittings can be substituted for a standard SAE flared fittings for enhanced protection against leakage due to normal system vibration.