This SAE Standard covers sub-critically annealed electric resistance welded flash controlled single-wall high strength low alloy steel tubing intended for use in hydraulic pressure lines and in other applications requiring tubing of a quality suitable for bending, double flaring, cold forming, welding and brazing. Material produced to this specification is not intended to be used for single flare applications due to the potential leak path that would be caused by the ID weld bead.
The grade of material produced to this specification is of micro-alloy content and is considerably stronger and intended to service higher pressure applications than like sizes of the grades of material specified in SAE J356 and SAE J2435. Due to the alloy content of the material, the forming characteristics of the finished tube are equal to or better, when compared to SAE J356 and SAE J2435. Nominal reference working pressures for this tubing are listed in ISO 10763 for metric tubing and SAE J1065 for inch tubing.
CAUTION: When brazing or welding is used as a tube end joining method, the structural integrity of the tube material can potentially be compromised due to the degradation of the areas affected by the thermal effect applied to the tubing; therefore, the ISO 10763 and SAE J1065 nominal reference working pressures may not be applicable.
Brazed and/or welded tube assembly configurations made to specific geometry and components bill of material in association with this material, may require qualification testing in accordance with ISO 19879 Test Methods for Hydraulic Fluid Power Connections. Cold forming the tube end configurations avoids this systemic testing by not compromising the tube material structural integrity.