Hi Jay,

My understanding is that snubber will not act in slow moving loads such as thermal loads but will be active in sudden shock dynamic load. The natural frequency of piping is dependent on both mass (m) and stiffness (k) of the system (sqrt of k over m), which the tendency of the piping system to respond to dynamic loads. Since snubber is a dynamic restraint it will be included in the stiffness term k of the natural frequency calculation but will not be included in static stiffness k so that it is free during thermal expansion of piping system.

Please correct me fellow stressers if my understanding is wrong.

Cheers!!!