Well Pump selection 1

[Sparky1949]

I have a well and a ground level storage tank. The existing well pump is failing. I need to select a replacement which is much smaller in order to minimize current draw on the electrical system.

Since there appears to be no useful excel sheet to help with the calculations for an old electrical engineer, who do I ask for assistance? (I have received some "calculations" but they are printed friction charts, catalog tables, and pump curves.)

I have measured the pipes, fittings, and elevations. I have the well data from a few years ago. I know the head in the tank and the GPM needed.

Who do I call to select the pump?

 

[LittleInch]

You're probably in the wrong forum - try the mechanical engineers pumps one (start a new post and link to this one), but if you supply the following info there are people here who will help you out.

Maximum lift in ft or m from your water liquid level in your well to the top of the liquid in your presumably atmospheric tank. This will define the amount of work per unit volume that you need to accomplish and the minimum head of your pump to simply pump it out of the ground. Base this on the worst level ever seen as if you don't get this right, you won't get any water....

Size of your hose or pipe from the pump to the top of your tank - this will define the additional head the pump needs to overcome in terms of friction based on your required flow rate

Maximum current at your voltage (220V?) that you have available.

The amount of electrical power you need in kW is 1.1 times shaft power which = Q(m3/hr) X H(m) X SG(1) / (367 x pump efficiency (%)). For small pumps efficiency can sometimes be quite low - so if you don't know try 60% to get you a figure to use.

If you are current limited then you might need to work this backwards to get a flow that is able to be pumped, but best to try an spread sheet and stick in some flows as the friction drop is heavily affected by flow (proportional to flow squared).

Apologies if this is very simple, but I don't know your level of expertise and understanding so best to start from the basics....



My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[LittleInch]

Did this help in any way?

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[Sparky1949]

Yes, thanks.