Vibration caused by spin fixtures?

[ptrepkowski]

How would you go about trying to determine the vibration caused by a simple spin fixture and dyno for testing engine components. I am working on a project that involves attaching spin fixtures to a base plate for testing purposes. The question is how to have the base plates attached to the floor whether to sink the base plates in the floor, bolt on to the floor, or use isolators for the vibration caused by a motor with the following characteristics:

40 hp - 1765 rpm
40 hp - 3525 rpm
33 hp - 4200 rpm

and a dyno with the following characteristics:

150 hp - 2500/6000 rpm


Please let me know how you would go about determing whether the base plate would have to be sunk in the floor, bolted to floor, or on isolators for the spin fixture and dyno due to vibration.

[FredGarvin]

It is impossible to say from the information given. The amount of vibration you are going to se will be dependent on every piece of rotating hardware. The major component of those vibrations will be the vibration due to imbalance. So, I guess the questions of how massive is the rotating fixture and how well is it going to be balanced.

From my experience, you can easily drill the floor, put some concrete anchors in and then bolt everything down. Why not just do that and move on with things?

[Shawnzyoo]

at work we use accelerometers to measure the freq/amp of rotating equipment
and then diagnose the problems from there on the computer
but sadly our set up is pretty expensive
but most of the motors i have seen that size are on some sort of vibrational isolator to dampen the forces
--shawn