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Flow control manifold

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BoomerSooner7

Industrial
Aug 4, 2008
73
We have a flow control manifold with three parallel branches with two branches having actuated plug valves on them and the third with a manual ball valve on/off. We use this to test centrifugal pumps at various points on the curve. The larger pumps flow around 2500 GPM at BEP. The fluid velocity through the manifold is around 45 fps at this flowrate. I know this is on the high side, but does anyone have experience with fluid velocities this high and the long-term impacts?
 
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Oh, forgot to mention we are flowing water that is filtered. Small particulates do exist.
 
If the material is carbon steel and the water is normal tap water, you can expect erosion-corrosion and wall thinning of the piping, eventually to failure, for velocities above 20 fps. Incolnel and stainless may be permitted up to a max of 75 fps. Copper and copper alloys have low velocity limits in most cases as well.
 
Do you inspect the manifold, UT or Visual? I agree with davefitz, you will see erosion/corrosion, but at what rate will be hard to say without having data.

If your worried about certain areas of your manifold washing out, inspect dimensionally or UT for thickness.




Petrotrim Services
 
My biggest concern at this point is the high vibration and noise we're seeing flowing at 2500 GPM. I sized the valve Cv's accordingly to handle the required pressure drop at the various pump sizes, which the valve engineer knew the flow rates we would be be seeing at the time, so he had to know the velocity through the valves. Even if I upsize the pipe we're still going to see the high velocity through the valves where it will be the highest and the noise will be generated at that point regardless of upstream and downstream pipe sizes. Rock and a hard place.
 
Booooooomer! :) Sorry, couldn't resist...

Pete
'88 BSME OU

 
The noise + vibration issues at the valve can be solved by using a multistage valve, such as a CCi self drag or yarway turbocascade or fisher Cavitorl IV.
 
Soooner! #1 baby, of course being #1 this year seems to be a curse, knock on wood. I sent data to the valve engineer at Emerson Process controls (these are Fisher valves) where I originally purchased them. Hopefully will come up with a cheap easy solution, did I just say cheap and easy? That's never the case is it?
 
They haven't called it that in years. In fact I can't remember when they changed the name to OSU. Even as a kid I remember it being OSU as long as I can remember. It was cool a couple years back when they wore the black jerseys with Oklahoma A&M on them for that one game.

 
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