Resonance occurs when a forcing function frequency is equal to a natural frequency.
A simple example of excitation of a natural frequency is plucking a guitar string. The string vibrates at its natural frequency and because of damping the vibration reduces in amplitude over time.
An example...
Yes and Yes...report it immediatly.
"Why don't you knock it off with them negative waves? Why don't you dig how beautiful it is out here? Why don't you say something righteous and hopeful for a change?" Oddball, "Kelly's Heros" 1970
Please see FAQ731-376 for tips on how to make the best use of...
Ask lots of questions of those who have "it" stored in their heads. Many of us old guys like it when the whipper snappers figure out that they don't know it all, and start asking questions.
Use reading eng-tips as a relaxation tool...
Read trade journals and other papers or what not as well...
As has been said, increase NPSHa...
"Why don't you knock it off with them negative waves? Why don't you dig how beautiful it is out here? Why don't you say something righteous and hopeful for a change?" Oddball, "Kelly's Heros" 1970
Please see FAQ731-376 for tips on how to make the best use of...
First company: 2 very different jobs in 5 years.
Second company: 2 fairly different jobs in 9 years.
Third Company: Same job for 7 years.
Fourth Company (hopefully last): same job for the last 3 years.
"Why don't you knock it off with them negative waves? Why don't you dig how beautiful it...
It would help to know where you are and what kind of piping you are working on (natural gas pipline? Refinery piping? Steam piping in power plants?). Also, are you at an engineering contractor or a operating company?
I would suggest that one approach is to get out of the piping design business...
Here is what happens when it doesn't work....
http://www.liveleak.com/view?i=cdd_1203701257
"Why don't you knock it off with them negative waves? Why don't you dig how beautiful it is out here? Why don't you say something righteous and hopeful for a change?" Oddball, "Kelly's Heros" 1970...
It is a hard flange coupling, not a clutch.
"Why don't you knock it off with them negative waves? Why don't you dig how beautiful it is out here? Why don't you say something righteous and hopeful for a change?" Oddball, "Kelly's Heros" 1970
Please see FAQ731-376 for tips on how to make the...
Ok, this generator is built like its bigger cousins... I assume that orbit is off shaft probes...
If the 2x suddenly showed up on synchronization would say that this is related to the generator rotor. That 2X in the probe trace is too symetric to be due to preload or misalignment and looks...
If it is any consolation I have had a hell of a time with screw compressors in VRU service as well... Cracked silencers, blown seals, other nasty problems.
And then there are the standard recip compressor issues in VRU service, failed valves, rings and riders...
So maybe a liquid ring is no...
We are beginning to look at using them for VRU, but I can't say I like the idea.. One of my main concerns is that my experience has been that they don't much like entrained solids. I am concerned that if you have gunk in the gas stream, which you always do on VRU, then you may wreck the machine...
What leads you to believe it is bore stress? Were the interference fit done improperly? Was the blower subjected to an operating condition it was not designed for? Over speed?
My experience with this sort of impeller failure is that it is much more often a funtion of impeller resonance...
Based on the 2X bode plot it looks like a structural resonance frequency excited by 2X running speed.
I assume that you do not have proximity probe data... Would be nice to see what the shaft is actually doing.
Since there have been repairs made, I would suggest looking for soft foot in the...
Anything over 6 hours is business class, no questions asked.
"Why don't you knock it off with them negative waves? Why don't you dig how beautiful it is out here? Why don't you say something righteous and hopeful for a change?" Oddball, "Kelly's Heros" 1970
Please see FAQ731-376 for tips on...
Dave this is the VP of HR, You are fired for firing someone on a public forum on the interenet.
"Why don't you knock it off with them negative waves? Why don't you dig how beautiful it is out here? Why don't you say something righteous and hopeful for a change?" Oddball, "Kelly's Heros" 1970...
