: Provides specifications for the sealing interface to ensure leak-proof performance under varying pressures and temperatures. 2. Technical Specifications
For new engineering designs, SAE International recommends using (Flareless Fitting End Design Standard) or (24° Cone Flareless Fluid Connection). Key Technical Specifications SAE AS33514 document
The difference was invisible to the naked eye—a slight optimization in the flareless seat dimensions and gasket seal interface—but at 3,000 PSI, physics didn't care about "close enough." The old fitting was microscopic millimeters off, causing a "weeping" seal that only opened under thermal expansion.
AS33514 FITTING END MECHANICS ___________________________ | | =============| Straight Thread (UNJ) |====== ( Tube Axis |---> [ 24° Internal Cone ] | =============|___________ ___________|====== | | <--- Gasket/O-Ring Seal |___| Boss Area 1. Core Engineering Tolerances sae-as33514
During a routine heavy maintenance check, a young mechanic named Elias was tasked with inspecting the hydraulic lines. He knew the history: AS33514 was originally a military standard ( MS33514 ) before being adopted by SAE International to keep commercial and defense parts unified.
It seals tightly without needing to bend, stretch, or flare the actual tube ends.
SAE-AS33514: A Guide to Aerospace Flareless Tube Fittings is an aerospace standard that defines the dimensions and requirements for male flareless tube fitting ends used in fluid systems. Originally developed for military applications under the designation MS33514 , the standard was transitioned to SAE International to ensure continued maintenance and relevance in the modern aerospace industry. Core Technical Purpose : Provides specifications for the sealing interface to
Manufacturers claiming compliance with SAE-AS33514 must subject their fittings to rigorous qualification testing:
This is the game-changer. AS33514 fittings feature a visual indicator (often a colored band or a mechanical flag) that is only visible when the nut has reached its retained torque range . No more guessing. No more "calibrated elbow." If you don't see the color, the fitting isn't safe.
The initial conversion from military sheets to commercial aerospace standards. It seals tightly without needing to bend, stretch,
The male fitting end features a precise 24-degree internal cone angle.
The SAE AS family includes several similar, yet distinct, standards.