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View Full Version : 12" pro spray vs 18" 1/2" nipple


duckworth
08-11-2012, 12:35 AM
Well produces 7gpm with 40psi.my question, is there more pressure loss through a 12" prospray with 2000mp or 18" 1/2" nipple with shrudhead and 2000 mp.if there is how much?

Mike Leary
08-11-2012, 12:21 PM
Well produces 7gpm with 40psi.my question, is there more pressure loss through a 12" prospray with 2000mp or 18" 1/2" nipple with shrudhead and 2000 mp.if there is how much?

How and where did you take your psi/gpm tests? That is a border-line well. I'd be looking at ALL my friction losses, especially main and lateral lines. Bring the pump guys in and test it for re-charge and drawndown. They might be able to adjust your 60-40 switch and the pressure tank before a stronger pump or a booster is considered.

duckworth
08-11-2012, 01:52 PM
Thanks for the advise ,but l think you missed my main question

Mike Leary
08-11-2012, 03:48 PM
Thanks for the advise ,but l think you missed my main question

Yup, and for a damn good reason.:rolleyes:

duckworth
08-11-2012, 04:10 PM
I take it there's no pressure loss when pushing 12 " riser up .sorry to waste your time .*trucewhiteflag*

Wet_Boots
08-11-2012, 04:35 PM
Pressure loss is zilch for the nozzles used with a spray body - A separate value is flow-by, the gpm escaping around the popup piston while the head rises into position

Mike Leary
08-11-2012, 05:36 PM
Pressure loss is zilch for the nozzles used with a spray body - A separate value is flow-by, the gpm escaping around the popup piston while the head rises into position

Which, in my early days, I've had happen, especially with 12" Stream-Rotors and Hunter low-drain check valves. It's not interesting standing there with the client with one's zipper undone and shoes un-tied. :dizzy:

Wet_Boots
08-11-2012, 05:48 PM
When the Rainbird 1800 with its improved wiper seal appeared, they gave the flow-by as zero. I created a zone of sprays and popup bubblers around a factory, of close to a hundred popups, that proved that the flow-by was definitely not zero.

Mike Leary
08-11-2012, 06:12 PM
I was called into a large commercial site where the LA swore he saw the heads pop-up during the walkthrough and failed afterwards. I could only figure that air in the lines gave enough pressure to pop the heads the first time, the second time the main was full and the heads failed and sat at complete flow-by. That was a good job for us, given the dipwads had not given us any spare wire. payup

Wet_Boots
08-11-2012, 06:54 PM
In my case, I simply added a second zone valve at a strategic location, and physically cut the zone in two, and ran them simultaneously to designed performance.

Flow-by was a headache on early popups that used a simple rubber sheet for both gasket and wiper seal, like the first of the toro 570 heads.

cjohn2000
08-13-2012, 01:13 PM
I was called into a large commercial site where the LA swore he saw the heads pop-up during the walkthrough and failed afterwards. I could only figure that air in the lines gave enough pressure to pop the heads the first time, the second time the main was full and the heads failed and sat at complete flow-by. That was a good job for us, given the dipwads had not given us any spare wire. payup

I had to learn this lesson the hard way. Did an install this spring where we had about 45 4" popups in a flowerbed and they were all 5' variety. We couldn't get the zone to pop up and seat. I only had an idea of what to do after my boss put a bunch of Hunter 2' h in his parking strip and checked valved half of it. So I threw about 25 check valves into the furthest heads and it worked. The customer saw it not come on the first time "why no work". Just an adjustment issue ma'am :rolleyes: