Which set of perforations would water be feeding from

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Fishyone

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New well 460' deep, 5 inch pvc casing. static water 60' winter to 90' summer. perforations at 430 t0 460 and 195 to 205. pump will be set at 240'. what will be the primary feeding set of perforations. Note that according to the e-log there is more water at the 430-460 perforations but plenty of water at the 195 to 205 perforations. reason for question is pump cooling as, i am told its best to set pump above the perforations
 

Reach4

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A flow inducer (inducer sleeve) could eliminate top-feeding worries, and even improve motor cooling for bottom feeding. If you don't find good construction info, ask.
 

Fishyone

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My worry with a flow inducer sleeve is that in a 5" casing with a 4" pump ...... well, if something is going to get stuck it will happen to me. hate to not be able to reach that 430 water if needed in the future.
As far as the perforations and which set would be the primary, would any consideration be given to the lower perfs and the pressure being more to try and get the water to the top vs. the mid level perfs.
Also if the water is rising to the static level would not the water from the lower perfs rise as well as the mid level perfs water rise. My point is if the pump is set 40' below the 200 ft. perforations and the lower water perforations are causing the water to rise, why would the motor cooling be any different
 

Reach4

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I think the only worry is if the sleeve can get past the pitless adapter shoe.

The sleeve can be held on by tape instead of a worm gear clamp.

SDR35 would give max clearance, I think.
 

Valveman

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A 4" flow inducer or shroud in 5" casing is the norm around here. It will fit past a 1" clamp on pitless or a weld on pitless. Water is going to take the path of least resistance, which is usually downhill. I would use a flow inducer unless you are able to set the pump above all perforations as you won't know if the motor is getting cooling until it is too late.
 

Reach4

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A 4" flow inducer or shroud in 5" casing is the norm around here. It will fit past a 1" clamp on pitless or a weld on pitless. Water is going to take the path of least resistance, which is usually downhill. I would use a flow inducer unless you are able to set the pump above all perforations as you won't know if the motor is getting cooling until it is too late.
But not a BX-10 trapezoidal type?


https://terrylove.com/forums/index.php?threads/idea-for-flow-inducer-construction.86907/ was an attempt to describe an idea for a minimum OD flow inducer. If made from SDR35, the OD would only be 4.215 inches.
 

Fishyone

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on this flow inducer.. the diameter of my 4 inch pump is actually 3.8". what pipe would be used to make the inducer that would not restrict the water flow to the pump. i looked at some 4 inch corrugated smooth inside drainage pipe today white on outside black on inside at lowes. (thinnest I could find) and measuring the id it was 3 7/8. how's the water going to get to the pump with out a restriction. schedule 40 pvc is about the same id with an od of 4 1/2. quarter inch clearance to wall of casing ? not much room for error.
 

Fishyone

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I've been looking at the different manufactures of sdr35 sewer pipe. What i come up with is, as you have stated, is an od of 4.215 however the wall thickness is .120 which i believe would make the id 4.095. noted on another tread that you say the id is 3.95. An id of 3.95 would be doable but 4.095 would only give the water 1/10 of an inch to pass to the pump inlet. that would seem a hard task for a 2hp 18 gpm pump. maybe not I'm not a pro. Not trying to argue here just trying to get the right information. might be best to set the pump at 180 ft. and if need be later, lower it (pass the planned 240) to say 400 thereby drawing from the 430 water. truthfully i doubt the water would ever get lower then the anticipated worst case of 120. Even with a draw down of 12 ft. i would still have 60ft of water in the down pipe.
I note that valveman states that its the norm in texas to use a 4" flow inducer in a 5" casing. After 30 gran just to punch the hole i can't risk something going wrong.
thanks for your input reach 4
 

LLigetfa

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What i come up with is, as you have stated, is an od of 4.215 however the wall thickness is .120 which i believe would make the id 4.095.
Double-checking your math, I get 3.975 for the ID so that is not right. You need to double the wall thickness since there are two of them in the OD measurement.
 

Fishyone

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interesting puzzle if your theory is correct then an id of 3.97 is still just a little over 1/10 " for the water to pass with a pump od of 3.83. are you going to get 18gpm being pushed by a 2hp motor through that space? interesting question, one that would take more knowledge of physics then i would ever have. Maybe Sheldon Cooper could figure it out !
 

Reach4

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I got my numbers from https://www.jmeagle.com/sites/default/files/GravitySewer_one-page-slick_v1.pdf

You are going to use a 1 inch drop pipe? Figure the area of that.

Do you understand the bit about annular space? That is the cross-sectional area inside the pipe minus the area of the motor cross section. Usually people cite 3.75 for the motor diameter. So I figure if the annular space is as big as the cross section of the 1 inch pipe, there is not going to be a lot of restriction. I understand that area is not the only factor, but I think it is close enough for this purpose.

Incidentally, if there may be some sand dropping from above, it would be good to have the flow inducer extend below the bottom of the motor. That way the velocity of the water in the big space at the bottom of the sleeve will be very low. You will have plenty of room below the pump.

See https://terrylove.com/forums/index.php?threads/looking-for-a-new-well-pump.96433/page-2#post-694003 #35 and more
 
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Valveman

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The drain pipe is the best you can find these days. There is more room than you think as the max OD of the pump includes the cable guard. Doesn't look like much room but I have tested it and there is very little restriction until you pump over 50 GPM.
 

LLigetfa

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You are going to use a 1 inch drop pipe? Figure the area of that.
Have you ever noticed that the suction side of a jet pump is larger diameter than the outlet side? Same logic applies here except for the length.

Anyway... once you have the true diameter of the pump without the cable guide, you can apply math or use an annulus calculator.
 
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