Machine Press Dynamic Loads

[Tony2009]

I'm designing a steel framed structure and foundation system for several presses up to 4500 tons (600,000 press weight). I have a pretty good handle on operating dynamic loads and but need help on determining the dynamic loads due to a sudden part failure. This is an "internal" force that creates large vibrations. How do I determine the force on the support structure?

 

[Bribyk]

Sounds like a spring & mass problem to me. You're basically storing energy by deflecting a structure with a given mass (and attached mass(es)). If you know the force and deflection you can calculate the acceleration (and, thus, force) of the masses when it releases.

 

[MotorVib]

A large mass under the presses works well to take care of the vibrations. If I remember the rule of thumb right 10 times the dynamic load will minimize the vibrations to the structure. The problem with this is that I have never run the numbers to check how true this is and what are the ground condistion for this to be true, it is just the rule of the thumb that a old engineer told me years a go.

Chris

"In this house, we obey the laws of thermodynamics." Homer Simpson

 

[Tony2009]

The "stored engery" is within the press. The heavy massed press frame will confine the broken part but vibrate when the part breaks. Sort of an internal explosion. I've designed the supporting structure for a vertical dynamic load of 100% of the press weight. My foundation mass is roughly equal to the press mass. This is similar to what I've designed in the past. Any additional thoughts would be appreciated. Thank you for your previous comments.

 

[BSE05]

There is a good article Principles of Foundation Design for Engines and Compressors which discusses rotary dynamics.
I think I downloaded it from Sliderule era's web site of good old material.