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Odd pump question?

Odd pump question?

Odd pump question?

(OP)
I have a 7.5hp submerged pump (well) gong into a pumphouse and not connected or used. Just a capped pipe. My question is this; can I use this well to water (irrigate) a surrounding 2 acre area. Has no reservoir, bladder tank nothing. Will I ruin the pump if I just run it and water the area?

RE: Odd pump question?

You can probably use this well/pump.  Has it been test pumped ?  Who built the well and installed the pump ?  What else do you know, or can find out about the well and pump ?  What do you know about water quality ?

good luck

RE: Odd pump question?

Maybe the real problem is how you will distribute the water.  If you pipe the water out to the 2 acres using too small of a diameter pipe, or if there are any significant uphill sections, your pump might not be the right one for that job.

http://virtualpipeline.spaces.msn.com

RE: Odd pump question?

I think you should consult you pump curve and the rated head and flow for your pump. Then you should figure out possible piping layouts for your irrigation system and examine the hydraulics of those options and how they compare with the ratings from your pump. Then you can decided whether the pump is inappropriate or whether certain modifications can be done to any of your irrigation options so that they are compatible with your pump. Also ensure that the well output is adequate for the rated flow of your pump.

RE: Odd pump question?

(OP)
Basically 7.5 hp pump 260ft well. 3600 gph. That is my question, I'm probably not going to use the pump to capacity at all. If I restrict flow to much will it harm the pump? Since I have no reservoir or tank for the excess to go.

RE: Odd pump question?

You probably won't harm the pump or motor if you control it properly.  Very few irrigation systems have either a tank or pressure tank ( what you call a "bladder tank") but simply discharge to the atmosphere through "emitters".

You pump/motor combination is capable of delivering 60 gpm (3600gph) @ 60% efficiency against a Total Dynamic Head ( TDH )  of 297 feet of water. You need a slowly opening and closing check valve on the discharge side of the pump to prevent losing prime, reducing water hammer and ensuring that the pump starts against some positive head.  The, you need to size the distribution piping to meet your irrigation needs within the limits set by the pump horsepower and well capacity.

good luck

RE: Odd pump question?

3600 gph = 4.5 l/sec - Typically a useful irrigation supply is about 4 l/sec. at this flow rate you may be irrigating for 4 to 6 hours per day. Maybe you don't need to throttle back too much ?

Another factor to consider is the capacity of your well - will it sustain a flow of 3600 gph.

RE: Odd pump question?

There has been several posts from a person, screen name valvecrazy.  This sounds like a good fit for the product he is always pitching, cyclestop valves.  

RWF7437 unless I misunderstand IMM600 is talking about a submersible pump.  Being under water it will already have a positive head to start against.  Also most pumps of this size have a spring loaded check valve built into the head of the pump.  The concern is depending on the climate, it may have to be removed so that in the winter the column pipe can drain back below the frost line.  

For cooling of the motor, Franklin motors requires that a 4" motor in a 4" well have a minimum flow of 1.2 Gpm
4"            5"                             7
4"            6"                             13
to meet the reuired flow of .25ft/sec.

RE: Odd pump question?


You need to examine the pump curve to determine whether or not that you will overload the pump motor if the pump runs out on the curve. That may happen if you are pumping against a lower head than the pump was designed to operate at.

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