Air suspension vs leaf suspension and axle torque loading

It depends on the method used to locate the axle under the trailer.

I built quite a few trailer axle suspensions when I was a young engineer. The types of suspension/axle system I am referring to is 20,000 pound axles, in single, tandem or tri axle configuration. Air ride suspensions typically provide a low natural frequency vertically. SOME air suspensions are rigid in roll and get their stiffness from moment attachment of the trailing arm to the axle. Typical axles are 5 inch outside diameter, and 1/2" or 5/8" wall thickness. Think of the axle as a torsion bar. The result is that SOME air ride suspensions can be more rigid in roll than leat spring versions.

Conventional leaf spring suspensions get their roll stiffness by spring stiffness.


bradley elwood

Thanks!