SAE J527 tubing brake line specification standard

Date:Jul 08, 2019

SAE J527_201710 standard specifies brazed Double Wall Low-Carbon Steel Tubing.


This SAE J527 Standard covers brazed double wall low-carbon steel tubing intended for general automotive, refrigeration, hydraulic, and other similar applications requiring tubing of a suitable quality for bending, flaring, beading, forming, and brazing.


SAE J527 references standards as follows:

SAE J1 677 Tests and Procedures for Carbon Steel and Low Alloy Steel Tubing

ASTM A 254 Standard Specification for Copper Brazed Steel Tubing

SAE J409 Product Analysis - Permissible Variations from Specified Chemical Analysis of a Heat or Cast of Steel

SAE J51 2 Automotive Tube Fittings

SAE J51 3 Refrigeration Tube Fittings - General Specifications

SAE J51 4 Hydraulic Tube Fittings

SAE J51 6 Hydraulic Hose Fittings

SAE J533 Flares for Tubing

SAE J1065 Nominal Reference Working Pressures for Steel Hydraulic Tubing

SAE J1290 Automotive Hydraulic Brake System - Metric Tube Connections

SAE J1453 Fitting - O-Ring Face Seal



 SAE J527_tubing_dimensions_tolerances_table_1



MATERIAL of SAE Tubing is made from low carbon steel, such as UNS G1 0080 or UNS G1 01 00.


Tubing End Condition is produced using normal mill cut-off practices. These practices can, but is not limited to single-cut ends, double-cut ends, saw-cut ends, and rotary cut ends. Care shall be taken to minimize the distortion of the tube ends. Ends that require further processing shall be by agreement between the producer and purchaser.


Mechanical Properties of SAE tubing shall have mechanical properties as tabulated in Table 2:


Properties Values

Yield Strength, min (0.2% offset) 1 70 MPa

Tensile Strength, min 290 MPa

Elongation in 50 mm 1 4% min

Hardness (Rockwell 30 T scale), max T65 (1 ) (2)

1 . Average of three readings not to exceed T65. 

2. The hardness test shall not be required on tubing with a nominal wall thickness of less than 1.65 mm. Such tubing shall meet all other mechanical properties and performance requirements.



The finished tubing shall satisfactorily meet the following performance tests. All tests are to be conducted in accordance with the procedures in SAE J1 677 or ASTM A 254 as designated.


Bending Test, Flaring Test,Nondestructive Electronic Test, Hardness Test,Flattening Test, Tensile Test, Pressure Proof Test SAE J1 677 Performed by agreement between purchaser and producer, (where allowable unit stress of material(s) =1 40 MPa (80% of minimum yield strength).

Inside Surface Cleanliness ASTM A 254.

Previous: SAE J528 automotive copper tubing specification standard

Next: SAE J517 Appendix A B C