Selecting a Submersible Pump

[zapatero]

I need to select a submersible pump for drawing water up from the river.

In rough terms, I would like a pump with a flow range of, say, 20 to 75 liters/minute, over a lift height range of 5 to 15 meters, (depending on the river's water level.) I have studied many performance charts and so far can only identify pumps that are either too powerful, or not powerful enough.

Is there anyone in TV that can assist me -- or if not, can you please point me to someone in the Thai commercial market that can make knowledgeable recommendations? English-language, if possible.

Thank you very much for any guidance.

~~zapatero

[Artisi]

What type of submersible pump/s are you looking at, borehole or sump type pumps?

[zapatero]

Hi Artisi. Sump type. Because of the geometry I'm thinking it would be more suitable for this particular installation.

[SantiSuk]

Maybe post a link to this thread under the same title on the farming forum (if ThaiV will allow that - I think they will as long as it is clear you are not wanting two threads to be running on the same topic - ie encourage respondents to reply on this thread)

[ksamuiguy]

flow and head to broad a range for an off the shelf "Divo"

Best to get an Inverter pump, or use a bore hole pump Lay it on its side , house it in a PVC pipe sleeve to protect and secure the pump. There is a drawing on the net on how to do this, as clearance around the pump is required for cooling.

[zapatero]

Hi SantiSuk. Done! Thank you for the suggestion.

Hi ksamuiguy: Not sure what a Divo is?

Can you please explain why/how an Inverter pump would solve this problem? (I am familiar with the term, but not with how it works.)

If you can remember where the bore pump/cooling link is, I would surely appreciate it. (It sounds like you have studied this issue, whereas I'm sure that I would find the wrong link.)

Thank you very much, ~~z.

Edited October 22, 2015 by zapatero

[zapatero]

I keep wondering -- couldn't the output flow of a pump that is too powerful be throttled down with a valve on the output side of the pump?

(I am still assuming a submersible pump.) Please reread my OP post above if our context has been lost... Thank you very much.

[RedBullHorn]

Hi SantiSuk. Done! Thank you for the suggestion.

Hi ksamuiguy: Not sure what a Divo is?

Google "Divo Pump"

Range from 150w to 1hp (1''-2'' outlet)... It's a "portable" submersible pump.

Edited October 23, 2015 by RedBullHorn

[ksamuiguy]

submersible pumps have very little lift.

Inverter pumps keep a constant flow depending on demand, but again HEAD is usually the problem, a pump doesn't like varying water levels.

So a small deep well pump works best, they can be laid flat in a PVC pipe (how to encase the pump is shown on the Grundfos web site) and will provide constant flow at very high heads, you can throttle the output with no problem. control the pump with either a pressure switch or a float valve in your water tank.

Low cost deep well pumps are available here on Samui. The added advantage they are usually SS pumps and will last a long time, but Not With out water, so a low water cutout switch in the source will prevent the pump from running if there is no water.

[zapatero]

submersible pumps have very little lift.

**Yep, I used the wrong word there didn't I !

Inverter pumps keep a constant flow depending on demand

**The only example I have so far been able to find of Inverter pumps is Hitachi -- and that is all in Thai. Is "constant flow" what "inverter" means? If not, can you please tell me what it means?

So a small deep well pump works best, they can be laid flat in a PVC pipe (how to encase the pump is shown on the Grundfos web site)

**I guess I'm getting too old -- I have spent several hours in the Grundfos site and still cannot find this. (However I believe you <g>) I did find their models SB and SBA though and they look like they might work for my application -- have you any experience with either of these?

file:Downloads/Grundfosliterature-5141099.pdf

Edited October 25, 2015 by zapatero

[zapatero]

Let me try again to attach that SB,SBA brochure file:

Do you know of a website where I can price this option, as well as your recommended "install-horizontal" borehole pump option?

Thank you very much !

Grundfosliterature-5141099.pdf