Thread 2945742

Would anything go wrong or be undesirable about using big 1.5/2/whatever" layflat hose with adapter fittings on a transfer pump designed for 3/4 GHT?

Looking to pump water ~300ft laterally but with a vertical rise of only about 10", thinking big layflat discharge hose would be good to reduce friction loss, and it packs smaller than garden hose. But I've never seen anyone do it, would it drop the pressure or something? Kink too easy because the hose is empty? Are these terminally stupid questions? I know the suction hose has to be equal or larger diameter.

>>2945742 (OP)
*10' not 10"

Yeah it can cause priming and velocity problems. Just use a garden hose

>>2945742 (OP)
You can put anything larger on the outlet side, it doesn't matter. On the inlet side, it has to be a solid structure pipe (ie. garden hose), obviously a roll-up pipe cannot be used for suction. For diameter, you'd likely have to manually precharge the whole hose and the pump to start pumping, if it's a very large pipe on a smaller pump that is supposed to be self-priming.

>>2945751
What kind of velocity problems?

>>2945764
But it should work normally if manually primed?

>>2945766
Yeah, a larger pipe just means less resistance, the pump doesn't give a shit as long as you meet its ratings. It's definitely not gonna be able to suck from deeper or push higher up at all, but you'll get better throughput from lower pipe resistance.
If you massively increased the outlet pipe diameter while keeping the original inlet pipe diameter, you could also potentially get cavitation that is long-term damaging to the pump's body, so try to not do that. Cavitation is noisy so you'd probably notice it's happening if it was happening.

>>2945776
Would a matched 1.5/2/whatever suction hose eliminate that possibility? Or could it arise from within the little intake pipe on the pump itself?

>>2945781
I would use the intended garden hose intake. A battery powered pump like that probably won’t benefit worth a damn.

Anybody know physics well? Anon’s “velocity issues” are bullshit, but a 2” hose full of water going up 10ft weighs a ton more than a 3/4” hose full of water. Does feet of head pressure or whatever account for the diameter of the hose/ volume or water you’re trying to push uphill? I would google that, like does blowing water up a 10’ verticle drinking straw require more work than blowing water through a 2” piece of PVC?

>>2945781
I'd just stick on whatever pipe I want and worry about problems later, if they occur.
>>2945797
The weight of the column doesn't change anything, only the height.

People use lay flat hoses to discharge water from backwashing pool filters without issue. It wouldn't work on the intake as others have suggested but I see no reason it wouldn't work for the outflow. It will hold a lot of water when done due to the rise but you can solve that by just lifting up the pump end.

>>2945909
>The weight of the column doesn't change anything, only the height.
Because the higher the water column is, the greater the weight of water in it. More water = more weight. More weight = greater head pressure.

>>2945932
The retarded tripfag was asking if, when you have more water in one body, as in a thicker hose, its total weight would have an effect on the pump. So the answer is, no, it doesn't matter if you have a 1mm diameter pipe that's 10m high or a 1km diameter pipe that's 10m high, both of them have the same pressure at the bottom, and the pump faces the same head pressure. The relation of the water column's height to pressure isn't related to total weight, only specific weight and height. P = h * ρ

>>2945939
That was the question. Too lazy to google the equation.

Is there more pressure at a 3/4” outlet on the bottom of a 10ft tall tank full of 20k gallons of water? Or a 3/4” garden hose 10’ long standing vertically full of water?

If physics says they’re the same, well I guess they’re the same. Gravity does what it does.

>>2946095
Somehow you don't sound like you're asking the question honestly. Like you're saying well obviously pfft it's the 20k gallon tank.

>>2946153
Because you have to go to the extremes to prove a theory like that. If a 20k gallon tank and a 3/4” garden hose standing vertical are both filled to the same height, and the 3/4” outlet at the bottom of the big tank is the same pressure as the bottom of the garden hose, then surely a 2” lay flat will be the same as the garden hose OP’s pump is designed for.

>>2945764
>You can put anything larger on the outlet side, it doesn't matter
Not true. If it has to pump uphill, the diameter of the hose plays a huge role in what the head pressure on the pump is. A 300' long 3/4" garden hose would have the weight of 0.9 cubic feet of water pushing back on the pump, where as a 2" hose of the same length would have the weight of 6.5 cubic feet of water pushing back on the pump. That's a difference of over 7x the head pressure between a 3/4" hose and a 2" hose.

>>2946338
>still doesnt comprehend how head pressure works
>read moody chart upside down
i have a floating millstone to sell you to tie around your neck as a pool floatie

>>2946338
You can’t forget friction losses in the pipe that reduces the available head.

>>2946341
Ok, but here’s the thing that I’m wondering about…

Is there like a hydraulics equation? Remember that force = pressure x area when it comes to hydraulics and such.

The area (cross section) of the 2” hose is wayy hueger than the 3/4”. So they’re both going to have the same PSI of head pressure for a given square inch, but you’re 2” hose is going to have more force overall (not pressure), and all of that force shoved down into a 3/4” adapter… lower pressure but high volume/area shoved through a small orifice often creates high pressure,

But I may be wrong, I need somebody to post their M.S. internet degree in fluid dynamics with the answer.

>294638nein no (you)s given for tripfags
pressure == force/area
force == pressure*area
the exposed area is the only point of acting force in the system
its nothing to block a pinhole @100psi but a shopvac blowing will float a sheet of plywood hovercraft @<1psi
this is the story of the little dutch boy with his finger in the hole in the dike

>>2946389
So if you go out to the beach and stick a straw under the ocean, you.got a 20quadbillion cu ft tank. Is the water going to shoot out of the straw like a cannon or is it going to match the same head as the ocean right next to it?

>>2946391
>little boy fingering a lesbian

Ok anon, I understand it now

>>2946392
The fingerbanging a dyke makes more sense.

>2” hose is going to have more force overall
a pump moving a fixed volume of water into a hose will move the water less far in the wider hose, as it spreads out. the 'work done' is the same.

Relatedly, how insane is it to hook up 1.5" hose to a garden spigot for a long run of that?

>>2946264
You can just take a 2" pipe and a 1/2" pipe at equal length, stand them up, fill with water, and put a pressure transducer at the bottom of both. Or you can even hook them up into a U-shape, but that'd probably be too much of a big brain move for (You) and >>2946338

>>2948233
It's a waste of money on expensive hose, but you do get noticeably less pressure drop over long (several dozen meters) runs compared to say, 3/4".