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ArTurf
07-31-2008, 11:25 AM
I need to know what I can realistically expect from a 2" water meter at 65 psi as far as gpm. I have worked with 1" meters and know what to expect. I would like to here about real life experiences with the 2". What size pipe did you use, etc. This is a very large property I will be working with and it would take too long to water with the 1" meter. Any advice would be appreciated.

Wet_Boots
07-31-2008, 11:30 AM
A meter is a meter. What exists between it and the water main? That's more important.

DanaMac
07-31-2008, 11:37 AM
A meter is a meter. What exists between it and the water main? That's more important.

Exactly. A 2" meter on a 1" feed reducing back to 1' is not going to achieve anything. Is it a full 2" supply or larger feeding the meter?

Wet_Boots
07-31-2008, 11:46 AM
I remember a job with a inch-and-half meter and supply line (copper) and 50-60 psi. Surely I could get 25-30 gpm no sweat. Well, it turns out the water main was on the far side of a divided highway, and the 400+ foot supply line outside was probably galvanized. Don't think I even saw 20 gpm.

ArTurf
07-31-2008, 11:55 AM
The city says it is a 2" line from the main to meter. They are saying it should flow 160 gpm but I know I cannot expect that. For those of you who have worked with 2" what do you usually plan a zone around with the specs I have given.

DanaMac
07-31-2008, 11:59 AM
The city says it is a 2" line from the main to meter. They are saying it should flow 160 gpm but I know I cannot expect that. For those of you who have worked with 2" what do you usually plan a zone around with the specs I have given.

Sorry, I don't have my charts handy. But you could think of one option. Under size the zones, and if the GPM is available, run two at one time. this gives you options if the PSI or GPM change down the road.

Yes 160 seems high. Very high.

Wet_Boots
07-31-2008, 12:05 PM
160 gpm would be the rated flow capacity of that meter, and you'd probably lose 15-20 psi in the meter at that flow. And what's the distance between meter and main?

ArTurf
07-31-2008, 12:09 PM
I am not sure if the main is on the same side of the road but if it is on the other side of the road it is at max 50 feet.

Waterit
07-31-2008, 12:20 PM
I'd think you could use 80-100 GPM no prob, but best to follow what Dana says - under-design, then see what you have when it's over.

OR you could just do a flow test, whether with a Mike Leary-type flowmeter or just the old low-tech stand-by, a 5-gallon bucket. Don't flow out of a faucet, tho, you have to go open discharge from your main.

Dirty Water
07-31-2008, 12:21 PM
The city says it is a 2" line from the main to meter. They are saying it should flow 160 gpm but I know I cannot expect that. For those of you who have worked with 2" what do you usually plan a zone around with the specs I have given.

City is clueless.

I'd say max safe flow is 55 GPM.

DanaMac
07-31-2008, 12:23 PM
but best to follow what Dana says - under-design, then see what you have when it's over.

:: falls over from heart attack ::

Waterit
07-31-2008, 12:24 PM
:: falls over from heart attack ::

Dude, just giving you some props...

DanaMac
07-31-2008, 12:31 PM
Dude, just giving you some props...

I know, that's what made me fall over. Hasn't happened lately. Thanks. :)

Wet_Boots
07-31-2008, 12:32 PM
This would be a case where the three-variable water-supply equation could be put to use, given Static Pressure, and a flow-and-pressure test giving you Dynamic Pressure and Flow, from which you could derive other flow-and-pressure combinations.

But of course, Magnet Boy insists there's no such thing :)

Kiril
07-31-2008, 12:41 PM
This would be a case where the three-variable water-supply equation could be put to use, given Static Pressure, and a flow-and-pressure test giving you Dynamic Pressure and Flow, from which you could derive other flow-and-pressure combinations.

But of course, Magnet Boy insists there's no such thing :)

And still no useful equation from Mr. Faded Tie.

AI Inc
07-31-2008, 12:43 PM
Faded tie? as in colledge professor as in courderoy sport coat and orange socks?

Wet_Boots
07-31-2008, 12:48 PM
Hey, I got the equation, and I'm keeping it on the QT. Maybe I can sell it :)

Orange socks are so gauche - argyle all the way!!

AI Inc
07-31-2008, 12:52 PM
I suppose ya want us to beleive that courderoy sport coat dosnt have patches on the elbows too huh?

lowvolumejeff
07-31-2008, 12:57 PM
For what it is worth, I have done greenhouses with 2" 50 feet supply, thru a 2 inch meter and found that 75 GPM is a safe assumption. Jeff

Kiril
07-31-2008, 01:00 PM
Faded tie? as in colledge professor as in courderoy sport coat and orange socks?

No, as in too cheap to replace them. :laugh:

ArTurf
07-31-2008, 01:11 PM
For what its worth I can't do flow testing as the meter is not yet installed. Just weighing my different options. For those of you who have worked with these similar specs did you use 1.5" valves or go with 2"? I'm thinking I would like to use 50-60 gpm per zone.

Kiril
07-31-2008, 01:14 PM
For what its worth I can't do flow testing as the meter is not yet installed. Just weighing my different options. For those of you who have worked with these similar specs did you use 1.5" valves or go with 2"? I'm thinking I would like to use 50-60 gpm per zone.

Not enough details. Do you even have a need for 2" valves? What are we talking about here with respect to square footage and landscape design?

ArTurf
07-31-2008, 01:19 PM
I am dealing with aprox 93,000 sq ft of mostly open grass.

Kiril
07-31-2008, 01:29 PM
::breaks down and cries::

Stick with 2"

Wet_Boots
07-31-2008, 01:30 PM
Definitely go with 1-1/2 valves for a 50-60 gpm design.

Kiril
07-31-2008, 01:59 PM
Definitely go with 1-1/2 valves for a 50-60 gpm design.

Wow .... such a bold suggestion from Boots with so little information, such as length of pipe runs, elevation changes, desired number of rotors per zone, etc...

According to boots precious charts, 60 GPM puts you well into the dangerous velocity range for 1.5" SCH40 PVC pipe. In order to stay within recommended velocities, you would need 2.5" for 60 GPM. 2" will suffice @ 50GPM, but just barely.

Wet_Boots
07-31-2008, 02:13 PM
Wow .... such a bold suggestion from Boots with so little information, such as length of pipe runs, elevation changes, desired number of rotors per zone, etc...

According to boots precious charts, 60 GPM puts you well into the dangerous velocity range for 1.5" SCH40 PVC pipe. In order to stay within recommended velocities, you would need 2.5" for 60 GPM. 2" will suffice @ 50GPM, but just barely.1-1/2 inch zone valves, silly. Stop playing with your magnet and pay attention. :hammerhead:

Kiril
07-31-2008, 02:22 PM
1-1/2 inch zone valves, silly. Stop playing with your magnet and pay attention. :hammerhead:

Pay attention Boots. Recommended max velocity for pipe AND fittings is 5 fps. Perhaps your going to use magic to reduce your pipe down to your 1.5" valve or maybe you could reinforce it with one of your faded ties? :hammerhead:

Waterit
07-31-2008, 02:26 PM
We did a Sam's Club and a Lowe's across the street from each other a few years ago. Both had 1-1/2" meters that gave us 70GPM@60PSI DOWNSTREAM of the backflow (2" DCVA).

Ran 2-1/2" sch. 40 main with 1-1/2" PGA valves for sprays and 2" PGA's for rotors, both piped through bottom (angle-style).

Had no problems with flow until some idiot utility contractor went back in to Sam's and up-sized storm drain, tearing out over 400' of mainline and then burying everything without letting anyone know they had hit anything. Took 4 days to get that mess straightened out, including pulling new control wire thru parking-lot sleeves.

Both systems still running as installed, pressure has dropped 3 PSI overall.

Wet_Boots
07-31-2008, 02:31 PM
Pay attention Boots. Recommended max velocity for pipe AND fittings is 5 fps. Perhaps your going to use magic to reduce your pipe down to your 1.5" valve? :hammerhead:Valves are not selected by way of internal water velocity. :nono: They are selected on basis of pressure loss and operating reliability. Did you miss the lesson about undersizing zone valves for increased operating reliability?

Kiril
07-31-2008, 02:37 PM
Valves are not selected by way of internal water velocity. :nono: They are selected on basis of pressure loss and operating reliability. Did you miss the lesson about undersizing zone valves for increased operating reliability?

Stop playing with your faded neck ties and pay attention. I'm not talking about valves, I'm talking about pipe and fittings. Did you miss the lesson on safe flow velocities? Personally I would not take a chance running 60 GPM through 1.5" PVC (fitting or pipe) as the flow velocity is nearly double (9.57 fps) the industry recommended max. Your choice, but IMHO that is playing with fire if you ask me.

Wet_Boots
07-31-2008, 02:51 PM
Why don't you talk about kazoos, then? The OP was asking about valves. Just valves. It happens that 50 gpm is in the 'sweet spot' for most 1-1/2 inch valves, regardless of what you might think about the velocity through the valve and adjacent fittings. Reliability is what matters. Get up past 60-70 gpm, and you can talk 2-inch zone valves.

Kiril
07-31-2008, 03:12 PM
It happens that 50 gpm is in the 'sweet spot' for most 1-1/2 inch valves.

Taking a page out of the boots book of obtuse behavior, for a 1.5" Century 100 valve I would say the sweet spot is 70 GPM, but then who pays attention to specs right? Ya know there is more to an irrigation system than just valves.

Wet_Boots
07-31-2008, 03:15 PM
Hold that thought. I'm going to the farmers market for some more razzberries. :p

Kiril
07-31-2008, 03:21 PM
Hold that thought. I'm going to the farmers market for some more razzberries. :p

ROFL ... get some extras for the other thread.

Mike Leary
07-31-2008, 03:26 PM
Hold that thought. I'm going to the farmers market for some more razzberries. :p

Pick up a six pack of 5' a second crow beer, too.

Wet_Boots
07-31-2008, 04:27 PM
Berries overpriced. Bought wax beans instead. And some corn.

AI Inc
07-31-2008, 04:28 PM
Good , support your local farmers, or watch open land disapear.

Wet_Boots
07-31-2008, 04:34 PM
Good , support your local farmers, or watch open land disapear.Damn straight. Little enough of it as there is. I liked the European farmer that was supporting obscure breeds of hog by "raising them and eating them" - One thing I do miss seeing much of nowadays is Silver Queen white corn. Some hybrid yields more. Taste is secondary.

Mike Leary
07-31-2008, 05:07 PM
I wish I had a Valet in service so I could figure the thread out.

Wet_Boots
07-31-2008, 05:17 PM
I wish I had a Valet in service so I could figure the thread out.You got the hat, what more do you need?

Mike Leary
07-31-2008, 05:31 PM
You got the hat, what more do you need?

I wish I still could get the 425hp solenoids and the Swiss clocks.

bicmudpuppy
07-31-2008, 06:11 PM
Given what you've been told, I would not be surprised to find out you could reliably get 90gpm. Experience would say that the 60gpm recommend here leaves Murphy chomping because he can't screw another irrigator. 1.5" valves with reducing MA from 2.5" to 2.5" work VERY well and are used a LOT. Using even 3' of undersized pipe will not create the velocity problem we try to avoid with the 5fps rule. Don't believe in the 5fps rule? here is a picture of what happens when you put a sprinkler on a QC that will run 60gpm and a valve shuts off the head a bit quickly. We had a beautiful fountain until I could get back to it and turn off the frost free valve before the quick coupler. AND, Yes, I KNOW the 1" Hunter valve shouldn't be operating that much flow, but I have about 100psi at the quick coupler and the old Royal Coach looks so GOOD spinning on it :) Going to invest in a galvy swing joint setup tomorrow and try it again :) I might have to drop back to the toro gun that was only putting out about 30gpm and shooting almost as far. And I haven't checked the old performance charts, I am using the pump station flow meter to arrive at that gpm SWAG. I had two hose end sprinklers running in the tree nursery at 28gpm steady. With this bad boy running, the flow fluctuates from 86 to 110gpm (the vfd adjusts at that flow and the flow reading is not consistent).

Mike Leary
07-31-2008, 06:24 PM
Any one who uses pvc for a quick-couple under that kind of pressure deserves exactly
what happened..bet it was overtightened. I like a brass swing joint when playing with
the big dog systems.

bicmudpuppy
08-03-2008, 08:58 PM
Any one who uses pvc for a quick-couple under that kind of pressure deserves exactly
what happened..bet it was overtightened. I like a brass swing joint when playing with
the big dog systems.

The risk you run when you inherit the system and don't know for sure what you have. The 2" frost free shut-off is a LONG way away (probably 75-80' and 4-5'below). The plans show these to be installed with 2.5" piping. Where it reduces, etc. I don't know, but I will get it dug up Monday. We don't leave the frost free valves on for extended periods, so I'm not afraid of using a galvy swing that might leak a bit. The QC is behind my 15th green and in the green fill, so drainage is fine. IF I can get the piping re-build so I'm comfortable with it, I want to try it again. Part of me thinks things may have been hurt by the sprinkler action on the quick coupler. I'm not sure how much of a swing joint is even down there. If the 2.5 or even 2" pipe is carried to the QC, then I see no reason I can't use the big Royal Coach. If for some reason it is 1.5" pipe, then I'm worried and will have to use the smaller sprinkler. I'll take some pics when it is dug up.