Motor / Pump Vibrating Whole system

[leeds25]

Could anyone help me on this please.

Whole system is vibrating as the motor is turned on. Its is diaphragm pump. Sample is kerosene.

Its connected directly to the pump (tubing SS) , we haven't used any hoses (Flexible)....

Could any one recommend a solution.... we havent used pulsation dampers... as its not piston pump.

Any help much appreciated...

Thanks

 

[leeds25]

Vibrating is more at inlet than outlet. All the gauages are vibrating and hard to read...

We have used vibration mounts as well..

 

[JJPellin]

A diaphragm pump is a reciprocating pump and is prone to pressure pulsation problems and cavitation. Given the very limited information you have provided, I expect that one or both of these are the problem. You should review the technical literature on both phenomena (Cameron Hydraulic Data has some good examples). You should contact a manufacturer of pulsation dampers and get a recommendation for your application.

Johnny Pellin

 

[BigInch]

Sounds more like a bolt-down problem. Get rid of the vibration mounts and get some real bolts.

**********************
"Being GREEN isn't easy" ..Kermit

http://www.youtube.com/watch?v=hpiIWMWWVco

http://virtualpipeline.spaces.live.com/

 

[micalbrch]

As written by JJPellin a diaphragm pump is a reciprocating pumps and as long as it is not an air driven diaphragm pump it behaves like a piston or plunger pump. The necessity of a pulsation dampener depends upon stroke volume, pressure and pump style (simplex, duplex, triplex). So, what pump do you have? Diaphragm pump alone does not mean a lot. But if the actual vibration problem did not occur when the pump was commissioned it will most probably not have anything to do with pulsations. I think it is a mechanical problem.

 

[SteveWag]

A diaphragm pump is a piston pump, get some pulsation dampers and consider the use of flexible tubing.
Steve

 

[leeds25]

Will test it with flexible hose ....

 

[BigInch]

Why ... you think the rigid pipe is causing the vibration?

**********************
"Being GREEN isn't easy" ..Kermit

http://www.youtube.com/watch?v=hpiIWMWWVco

http://virtualpipeline.spaces.live.com/

 

[leeds25]

We got the vibration mounts , fixed securely to base plate.

Flexible hose , I am hoping would take the vibration , or atleast part of it ...rather than oscillating the whole line.

Seen previously , flexible hose used ... hence i am hoping it works ..

Whats ur notion against flexible hoses??

 

[BigInch]

I don't like things that vibrate, they always come loose or break, just a matter of time, so I don't use vibration mounts or flexible pipe, unless the foundation is what's vibrating the pump.

**********************
"Being GREEN isn't easy" ..Kermit

http://www.youtube.com/watch?v=hpiIWMWWVco

http://virtualpipeline.spaces.live.com/

 

[leeds25]

So is it just u mount it securely to base plate , and tube it directly..

Did u ever have to use the pulsation dampers then ???

 

[BigInch]

Yes, if fluid pulsations are the result of fluid moving in the pipe, and that's causing the vibration, the dampners will work. If the vibrations are the result of unbalanced forces due to pump motion, pistons, levers, fluids, you have to balance those, or bolt it down if you can't balance them, to stop it. I suppose, if you can't balance it, or bolt it down to a big enough foundation, you've got no alternative except to let it vibrate and design for its eventual failure.

**********************
"Being GREEN isn't easy" ..Kermit

http://www.youtube.com/watch?v=hpiIWMWWVco

http://virtualpipeline.spaces.live.com/

 

[JJPellin]

You need to study the technical literature, as I suggested. If the vibration is a result of pressure pulsation or cavitation, then pulsation dampers are the proper solution. If the vibration is a result of mechanical forces, then mounting could be a potential solution. I expect that running the calculations as called out in Cameron Hydraulic Data will reveal a pressure pulsation problem with your system design. But, I can't evaluate that possibility because I don't have the needed data. You do.

Johnny Pellin

 

[micalbrch]

leeds25: Do two simple things. Send us a photo of the installed pump and answer the question "Did the pump vibrate from the beginning (when it was commissioned) or did the vibrations occur just recently." I'm sure with the photo (that shows the whole pump) and the answer to the question we can move a big step forward in finding a solution.

 

[relentlessratt]

I agree with Johnny Pellin. Have a look at the Cameron hydraulic data - pressure pulsation might be your problem. You also need to check acoustic design of the piping system as this can also be your problem.