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Setting up a vibration envelope

Setting up a vibration envelope

Setting up a vibration envelope

(OP)
Hi,

I have been given a vibration envelope that I have to test a product based on. I am using a Vibration sofware that I enter a profile for the vibration using Hz and G^2/Hz as the x and y axis. I cannot figure out how to set up the profile as it is given in varying units and I am new to vibration testing. The envelope is as follows

Magnitude       Frequency range (hz)
 
0.030" pk-pk    10 to 37
3.5"/sec pk     37 to 350
20g pk          350 to 3000

I thought this was a sine vibration initially but our customer said it was random. Any help would be greatly appreciated.

Thanks,
Ben

RE: Setting up a vibration envelope

What?? I have never seen this before.  May be others on this board can help, but when I see Pk to Pk that is sine wave language.  Maybe just ask the customer to give you a break point table in G^2/Hz per Hz instead so that you don't have to fumble around converting it.  If the customer is a vibration person, it should be easier them to do it since it is their profile.

Tobalcane
"If you avoid failure, you also avoid success."
"Luck is where preparation meets opportunity"  

RE: Setting up a vibration envelope

(OP)
I think you may be right, I have done sine profiles before and these units resemble the ones I saw there. Our customer may also have slipped in there knowledge of vibration and assumed it was random.  

RE: Setting up a vibration envelope

This looks perfect for a sinusoidal vibration... usually since the vibration shaker cannot handle all ranges of disp, vel, & acccln, the specs looks quite normal. May be you should consult a vibration test lab with the specs and they might help u

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