Water pump capacity / flow and pressure question

Hi Roy, As I understand everything, it should work just fine. You're pulling from the bottom now, right? What do you strain the pick-up with? A well point? The pump will do 10 feet, that's 10 vertical feet right? It doesn't matter for horizontal runs except for friction and constrictions.

Should be the same

I owuld think

The water will flow from the pressure source to the taps, it will follow the path of least resistance.

You'd only be pulling 5'. There will however be some head loss due to the friction of the water flowing in the pipe. Considering that your pump is not running at max flow (as indicated by the throttled down valves and your statement about the pump making pretty good pressure) if you stick with a 1" suction you'll be fine.

and do you think this extra length even thoughi ts vertical in

On Fri, 06 Aug 2004 00:00:00 GMT, snipped-for-privacy@hotmail.com (Roy) vaguely proposed a theory ......and in reply I say!:

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If you are pulling from 10' below the pump and the whole thing is underwater, then you are pulling only against the friction in 50' of pipe. That 10' of lift assumes that the lift is through air, not water.

In other words, basically the only bit that matters is what's out of the water.

It's not atmospheric pressure, but water pressure, that is going to help.

As I say, you will lose something in that 50' + line. Make it as big as possible.

On Fri, 06 Aug 2004 00:00:00 GMT, snipped-for-privacy@hotmail.com (Roy) vaguely proposed a theory ......and in reply I say!:

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It depends on flow a bit. But using the Engineering Power tools programme, for all flows, the loss in pressure per 100m (same as per metre when you are comparing pipe sizes) shows 40mm (1.5") pipe to be around 8 times as good as 25mm *1").

It also seems to me that since, as far as I understand your description, you have two "U"s, you have two lots of 1.5" pipe. You will lose a bit round corners over flowing bends. I guess it depends on distances, bends to the outlet etc. But it sounds as if you should walk it in.

Since you already have to cut down the flow with ballvalves, it sounds as if you also have a lot to play with.

On Fri, 6 Aug 2004 02:05:02 -0400, "Shawn" vaguely proposed a theory ......and in reply I say!:

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More pedantically, it will flow in inverse proportion to the resistance of each path. Every path available will contribute _some_ flow.

On Fri, 6 Aug 2004 02:05:02 -0400, "Shawn" vaguely proposed a theory ......and in reply I say!:

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Sorry. Posted too soon. What I said could be more than pedantry.It may help to decide where to place the pump outlet in the piping syste, so that the highest flow outlet has the shortest run, etc.

Yes, I am puilling intake water from the bottom so my depth at which I am pulling from will not change, just the distance from the pump to the inlet will be increased not by much anyhow, perhaps a foot.

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