This SAE Standard covers specifications and performance requirements for 37° and 45° single and double flares for tube ends intended for use with SAE J512, SAE J513, SAE J514, and ISO 8434-2 connectors. The flares described in this document are intended for use with SAE metallic tube materials. Considerations such as the effects of wall thickness selection for specific working pressures, identifying appropriate length of thread engagements for specific applications with mating connectors and other associated criteria, shall be the responsibility of the user. For applicable nominal reference working pressures for hydraulic tubing, see SAE J1065 and ISO 10763.
The SAE J533 specification has been in use for over 50 years and has served the original equipment industry well. The flares defined in SAE J533 are still extensively used in the automotive industry, on industrial equipment and on specific applications by original equipment manufacturers. Some users find the basic description of the flare seat surface in the current standard somewhat lacking in details associated with key attributes and how they relate to the physical characteristics of the formed material. This revised document uses Geometric Dimensioning and Tolerancing (GD&T) to define the face of the flare sealing surface. The use of GD&T tolerancing based on the total runout of the flare surface allows for the use of check fixtures during production, which can improve the quality of the finished product. Additional tables were added to incorporate metric tube sizes and a depiction of an inspection gage example for checking total runout was added.