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Max flow rate through pipe

Max flow rate through pipe

Max flow rate through pipe

(OP)
How do i find the maximum flow rate of fuel through a 7 inch pipe?

RE: Max flow rate through pipe

do a search here, there are several dozen posts on how to do that.

BobPE

RE: Max flow rate through pipe

7 inch pipe?  Is this a culvert or water pipe?

RE: Max flow rate through pipe

It could be REALLY OLD pipe as well. They used to make 4-1/2", 7", 9", 11", 13", 15" etc.

RE: Max flow rate through pipe

If only the search engine wasn't down for "routine maintenance"

TTFN

RE: Max flow rate through pipe



1000 gpms

RE: Max flow rate through pipe

hacksaw:

Do tell............just how did you figure that out?   I figure if I put this one pump on that pipe that I saw in a book, I could get 1,000,000 gpm through it.....lol

BobPE

RE: Max flow rate through pipe

I don't know if this is a "wind up" or not, but I'll answer it anyway.

There is no (practical) "maximum flow rate of fuel through a 7 inch pipe".  As BobPE says in his last post, "I figure if I put this one pump on that pipe that I saw in a book, I could get 1,000,000 gpm through it.....".

I'm sure that if I look through my catalogues for a few minutes, I can find a pump that will shift two-times, three-times, ten-times...etc that much!!!

On the other hand, if you have a limiting factor within which you want to stay (say an average pipe velocity of 1.5 metres per second), then the maximum flow rate would be:

Pipe Internal Diameter 7 inches (say 0.175 metres)
Pipe Area about 0.025 metres squared (pi x (dia^2)/4)
Pipe Velocity 1.5 metres per second
Pipe Flowrate 0.025 metres squared X 1.5 metres per second = 0.0375 metres cubed per second (34.5 litres per second)

Sorry about the metric units!!!

Regards,

Brian



RE: Max flow rate through pipe



Okay, 2000 lpm ~ 4400 lb/min

at 8.33 gals/lb (water) that's 528 gpms.

most plants run a little better than 1.5 m/s so 1000 gpm is a good upper limit and the answer to the original query...

RE: Max flow rate through pipe

kcons5055

There is no single answer for your question based on the info you gave.  If I assume you are pumping with metal pipe and want to know the friction losses you should use the Hazen Williams formula:

F= 2.083(100/C)^1.85 (Q)^1.85/ID^4.8655

Where:
F= Feet loss per 100 feet
Q= Flow in GPM
C=120

Once you calculate the friction loss you can look on your pump curve and see what flow to expect.

If you have an existing pipe and want to know Qmax in order to buy a pump several things to consider are:

The friction loss cost or opX.  If you are talking about 5 feet or 5000 feet will change any answer given.  Your need for pumping the fluid verses the associated friction loss is something that you need to determine.

Fluid velocity will cause erosion wear or failure.  Not knowing the "FUEL" you want to pump makes any answer questionable.  If you are pumping a somewhat corrosive liquid you would want the velocity low to avoid combining both corrosive and erosion problems in your line.

The expected length of service for the operation needs to be considered to make pump / tubing decisions.  If you are only going to pump for one day you may want to consider Bob’s million GPM pump.  It may survive.

Being fuel I doubt that you have any solids.  If you are pumping solids such as sand, rocks etc. you will want the velocity high so the solids won’t “fall-out” in your tubing.  Any discussion that I have heard about recommended fluid velocity seems to be qualified by what is being pumped.

The numbers that I have heard in the petroleum industry range from 2 FPS to 15 FPS, but those numbers can change dramatically based on any variables that you may add.

David

RE: Max flow rate through pipe

Maybe if the original poster would supply some more information what they are looking for (hint, hint), we could provide them with some more applicable information.  Not slamming anyone here for what they have said, this is a matter of not knowing what the OP really is looking for.

RE: Max flow rate through pipe

You are right TD2K, I just couldn't resist.....I think the short of everyones busting was that we do need more info....


Take care

BobPE

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