Spray Bar Hole Sizes

Goldhunter78

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I am using a 1200 gph 12v bilge pump & 1250 gph 12v bilge pump with two 1" x 12" pvc Spray bars. The pump hoses are not connected together, rather connected to two individual spray bars, but the pvc is connected together further down the box. What size holes and how far apart for adequate spray pressure and water flow? Used on 10" wide Keene sluice/highbanker"


The highbanker I created uses a keene a51 at a reveresed downward angle that is attached to a Keene a52 going the other way. Imagine an open alligator mouth.



Thank you
 

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jeff of pa

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Moved to Gold Prospecting.
I believe it Fits here Better ?
 

ratled

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GH have tested the pump on the A51 to see if you have enough flow for the riffles to work .....properly?

ratled
 

Jeff95531

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Your set up is like mine. I used 11/2" feed reduced to 3/4" at the header box. I went with 1/8" holes to start and slowly worked up to 5/32. Your holes can be as big as the pump, rise and plumbing will allow in your set up. For example, 1/8" x's 8 holes means you are letting out a 1" hole overall.The problem with spray bars is the holes plug up. I have to poke the holes with a rod while running and open up the caps at the end of the spray bars to flush it all out. I just saw this and will likely change my set up to this for 2017. Just heat, squeeze, cool and install. :icon_thumleft:

https://www.youtube.com/watch?v=KKwrtviiehk&feature=youtu.be
 

et1955

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Your set up is like mine. I used 11/2" feed reduced to 3/4" at the header box. I went with 1/8" holes to start and slowly worked up to 5/32. Your holes can be as big as the pump, rise and plumbing will allow in your set up. For example, 1/8" x's 8 holes means you are letting out a 1" hole overall.The problem with spray bars is the holes plug up. I have to poke the holes with a rod while running and open up the caps at the end of the spray bars to flush it all out. I just saw this and will likely change my set up to this for 2017. Just heat, squeeze, cool and install. :icon_thumleft:

https://www.youtube.com/watch?v=KKwrtviiehk&feature=youtu.be
Have you tried putting a screen on your pump to prevent debris from clogging the spray bar
 

Jeff95531

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oh yeah. The first tub catches what comes outta the sluice and is screened upon overflow into the second tub. Then thru a cage/filter I built for the pump as well. Bars plug the most when I run unclassified buckets.
 

Capt Nemo

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Your set up is like mine. I used 11/2" feed reduced to 3/4" at the header box. I went with 1/8" holes to start and slowly worked up to 5/32. Your holes can be as big as the pump, rise and plumbing will allow in your set up. For example, 1/8" x's 8 holes means you are letting out a 1" hole overall.The problem with spray bars is the holes plug up. I have to poke the holes with a rod while running and open up the caps at the end of the spray bars to flush it all out. I just saw this and will likely change my set up to this for 2017. Just heat, squeeze, cool and install. :icon_thumleft:

https://www.youtube.com/watch?v=KKwrtviiehk&feature=youtu.be

8 x 1/8" holes does not equal 1" diameter of pipe. It's more like slightly under 3/8" diameter pipe. As long as the combined surface area of the holes stays less than the surface area of the feed pipe, you'll have good pressure at the holes.
 

QNCrazy

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If necessary, use 1/2" pipe for the nozzles. Use 1" x 1/2" tees. Be sure to post pics of your work.
 

Jeff95531

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8 x 1/8" holes does not equal 1" diameter of pipe. It's more like slightly under 3/8" diameter pipe. As long as the combined surface area of the holes stays less than the surface area of the feed pipe, you'll have good pressure at the holes.

Yes. It will be less than 1" overall. When I built my sluice, it was all explained to me by a previous knowledgeable member here (Chris Fabrication Specialist for the ol timers here) and he rounded on the conservative side to make sure I was happy (and in layman's terms cuz well, I am). And it all worked, the GPH, reductions, and expected flow was dead on. So I thought I would pass it on. Agree with the second part 100% tho.
 

IMAUDIGGER

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The answer is "whatever works best". Really - mining equipment is usually modified, then modified again until the operator is happy with the results.
Start small and add more holes or drill them out larger.
 

Goldwasher

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and bilge pumps are terrible at handling pressure
 

et1955

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Bilge pumps are designed to push water not pressurize it, any resistance and water volume in the line will slow down the pump and reduce water flow. The higher the head the less pressure you will get " Head refers to the ability of a pump to push water strait up " bilge pumps are terrible at this.
 

russau

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I use 3/16 dia. holes in spray bars because of the streams I worked had a LOT of turbidity/sand in the muddy water and that caused me some plug ups in the spray bars. PLUS I made a access port that I could open and flush out any sand that caused my plug ups AND on the bottom of my pump I drilled and taped a 1/4 inch valve to drain / flush my pumps occasionally to clean it out and when the temps drop , then I could drain it without the thought of it freezing at night (or when traveling) and cracking something!
 

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