hydreaulic calculation for water pump

Please see the following thread for some good free download information:

http://cr4.globalspec.com/thread/30464 (especially the "Light My Pump" book)

and then have a look at this site:

http://www.engineeringtoolbox.com/pipes-fluid-flow-pressure-loss-t_18.html

and, once you have a basic understanding down, don't hesitate to ask more questions.

The pump supplier / designer had all the relevant data at hand when he selected the pumps. It is therefore assumed that the 2 wells are basically identical regarding water depth, static to tank etc.

The only difference would then be the additional friction through the additional pipe. The difference guesstimated at between 1 to 5 m would imply that pump 2 will have a slightly smaller flow.

Feel free to supply us with more information for better advice.

Each Pump has duty point; duty point means the flow rat against the head /Resistance facing the water flow,the flow will minimize if the Resistance is increased. (this is a fact) secondly in your case as normal the resistance is consist of two reasons 1- the vertical depth from submersible pump to the inlet of the tank, please measured vertically, each 10 m = 1bar, 2- the resistance of the flow due to the friction between water and the internal pipe surface, this of course depend on

a) pipe material type Mostly you are using PVC pipe Is not it?

b)pipe diameter.

c)pipe length ; means total length vertical and horizontal,there is a charts for the same email me pipe dai. ,type and total length and I will help you.

Regards

The information posted by others should get you what you need, but I am interested in the rate of water recovery in the wells. If they are at 250 meters apart and you are drawing from the wells at 60 m3/hr each well, you must be taped into a large aquifer source or you could starve the pumps if the recovery rate is insufficient.

I need more information to answer your question properly, however, with the following provision that,

1. two deep wells are horizontally same in elevation

2. two well pump's install elevation are all same

3. two well pump's discharge piping is connected or individual for both, two well pumps are discharging the normal flow in any case

4. Discharge piping size is same through the entire discharge line

Your system is already perfect. Perfect means more than enough.

Since both pumps are running properly, either 1 or 2 pump is out of order, you can run the other pump. The friction loss in horizontal piping line is extremely small when compared to the vertical friction loss.

Furthermore, if 2 pump is running (simultaneously with 1 pump or independantly alone) well, this means that back pressure by pump 1 (that can occur when two pumps are running) can be eliminated when 2 pump is running alone. This will make the pump producing more head and pumping will be more smoothly.

You do not need any further calculation actually.

Calculation of friction loss will require you to know the total piping line length, number of valves and their types, total vertical difference and others. Remember one thing. such calculation requires many information, but calculation itself is very easy one.

Total friction loss = Vertical difference + coefficient * total piping length + Sigma (coefficient(n) * number of valves(n)) + safety factor (20%),

n = each valve type, piping friction loss may differ from the size of piping

Process engineers will give you more precise equation, but again, you do not need it. Your pumping system is already more than enough.