pressure and head equation

If you are asking the simple question of converting a known pressure measurement (psi/bar) into equivalent 'head' units then the equations are:

head [ft] = (p [psi] * 2.31)/SP

where SP = specific gravity of liquid

OR

head [m] = (p [bar] * 10.197)/SP

If you are asking for the more difficult problem of what pressure your pump will produce - that is a more involved calculation which takes a lot of other factors into account (mainly where your system curve intersects with your pump curve).

what kind of head that u need to...

1.Suction Head

2.Discharge head

3.Or Total static head of the pump

i need the height of (the eye) the pump from the water surface

and the type of the pump , axial or centrifugal...

if i get the information i'll calculate it for you

Head:

The pressure at any point in a liquid column can be caused by vertical column of the liquid due to its weight. The height of the liquid column at any point is called the static head and is expressed in height of liquid. The same head term is used to measure the kinetic energy created by the pump. The static head corresponding to any specific pressure is dependent upon the weight of the liquid.

Head (H) ft= Pressure (PSI) X 2.31/specific gravity

Or

Head (Met)= Pressure (bar) x 10.2/specific gravity

In case of water specific gravity is 1 and so

Head (ft) = Pressure(PSI) x 2.31