Pipe Flow Capacity?

[npaden]

Actually that calculator is strictly for the height of the water in the container from my understanding.

As for an actually calculating your exact plumbing situation Louey, it is too hard for me!!

Alot easier to speculate and theorize than it is to calculate a specific example!!

BUT!, I think that you will be right on the borderline pushing 1,500gph through a 1.5" drain with your setup. If you can go to 2" drains you will be in great shape. It is always better to overkill on drains.

HTH, Nathan

 

[Anonymous]

Thanks Chris. You post does help.

I think my 1.5" drains will be fine. I may add a gate valve on the return pumps to dial them back a little if I have two. It's to late to go with smaller pumps or bigger drains.

Louey

 

[npaden]

Oh yeah, if you wanted to add some safety margin to the setup you could set your durso so that it was about 6" below the top of the overflow. Then if something happened to slightly clog it and the water started backing up in the overflow it would add pressure to the drain and would have 6" to work before overflowing.

The difference between 6" of water over the drain and 1" is 1,104gph using that calculator. Of course you wouldn't want that setup on a full time basis because it would basically be like a toilet flushing over and over again but it would be a bit of a saftey margin if you are pushing the max volume of the 1.5" drain.

FWIW, Nathan

 

[Anonymous]

Oh yeah, if you wanted to add some safety margin to the setup you could set your durso so that it was about 6" below the top of the overflow. Then if something happened to slightly clog it and the water started backing up in the overflow it would add pressure to the drain and would have 6" to work before overflowing.

The difference between 6" of water over the drain and 1" is 1,104gph using that calculator. Of course you wouldn't want that setup on a full time basis because it would basically be like a toilet flushing over and over again but it would be a bit of a saftey margin if you are pushing the max volume of the 1.5" drain.

FWIW, Nathan

I don't think it would do the toilet flushing thing. I think you'd get a steady state thing going, as long as you had the airline to the top of the durso receiving air the whole time.

Here's a pic of my Durso on my old 125. It's a junk pic but what it shows is the water level in my overflow about 2" higher than it should ideally be. I was pushing the limits of what the drain could handle. Anyway, the water level consistently stayed up there above the air hole, so I added a small piece of PVC pipe around it to keep it 'breathing'.

Obviously you guys know a hell of a lot more about the physics of this than I do but maybe this is a possible solution without having to ramp back the pumps. Drop the standpipe a bit and keep the airline above it. I guess it's kind of risking disaster if something should block it though...<shrug>

 

[ChrisRD]

I think my 1.5" drains will be fine.

I think you're going to be OK with two 1.5" drains too - especially if you're going to use penductors/eductors on your return lines (which will restrict the pumps considerably).

 

[Anonymous]

Cool. Thanks to you and everyone else for helping me figure this out.

Next time I'll do the planning first then the ordering, lol.

Louey