Expansion Joints with FPS pipe
Expansion Joints with FPS pipe
(OP)
Some of the pumps I am replacing currently have expansion joints. Does anyone have some good resources on why we should use expansion joints? The pumps' suction operate under a slight vacuum and the system engineer told me there may be some flashing going on at the impeller....this indicates to me that the pumps are operating pretty rough. Our replacement pumps have a better base design but will expansion joints help the vibration issues with the pumps??
Thanks in advanced.
Thanks in advanced.





RE: Expansion Joints with FPS pipe
EJ helps reducing the nozzle loads.
EJ is not for vibration remedy and as a matter of fact vibration can be very detrimental to EJ.
Are you limited in space around pump suction? If yes, then we can not deal with required flexibility with adding pipe fittings e.g. elbows, ..
RE: Expansion Joints with FPS pipe
Since the pipe is just FPS, there shouldn't be any major loads on the suction or discharge correct?
RE: Expansion Joints with FPS pipe
Is it a non-metallic material? Like PVS, FRP, HDPE,...
RE: Expansion Joints with FPS pipe
The existing piping were carbon steel (metal)?
RE: Expansion Joints with FPS pipe
There are a total of 4 identical pumps we are replacing, where two of them indeed have expansion joints on the suction/discharge. Since Fiberglass piping is fairly brittle, this may be why they used expansion joints? Reduced nozzle loads would be helpful since the existing pumps are operating pretty rough.
Here are the expansion joints we are wanting to use.
http://www.mercer-rubber.com/mercer/html/5.htm
Thanks for your help so far!
RE: Expansion Joints with FPS pipe
I concur with what you said.
And as these are rubber EJ, they help isolating the vibrations.
Just watch for the temperature, FRP and rubber can go up to 70 to 90 degree C.
RE: Expansion Joints with FPS pipe
As far as length of exp joints. Is there a rule of thumb for the maximum recommended length you should have them? we are connecting to a 12" pump flange...
RE: Expansion Joints with FPS pipe
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