Steel Tubing Pressure Ratings
Pressure Ratings, Steel Tubing for General Hydraulic System Applications
The following chart lists the nominal pressure ratings of tubing products which conform to SAE J524, SAE J525, SAE J526 and SAE J365. These pressure ratings are derived from the Lame formula with 12,500 psi (86 MPa) allowable stress factors and approximately 4:1 design factor. Pressure values shown in bold are for tubing wall thickness normally considered suitable for 37 degree single flaring to SAE J533. Many factors influence the pressure at which a hydraulic system will perform satisfactorily. The values shown below should not be used as a standard or specification and are not to be construed as guaranteed minimums.
Note: For single flaring to SAE J533, SAE J524 or J525 tubing is recommended. For double flaring applications, tubing to SAE J 524, J525, J526 or J356 can be used.
Calculation of Design Pressures for Alternate Tubing Materials
Design pressures for alternate tubing materials may be calculated using the Lame formula as follows:
D= nominal outside diameter of tubing
d= nominal inside diameter of tubing
P= design pressure
S= allowable fiber stress of material at 4:1 design factor
Design stress and temperature derating factors for typical hydraulic system tubing materials and temperatureranges are listed below. Derating factors for SS-304 and SS-316 are derived from ASME 831.1-2012 Edition.Carbon steel tubing in these temperature ranges does not require derating.