PUMP HEAD PRESSURE For the Novice

The terms PUMP HEAD PRESSURE or PRESSURE HEAD is really describing how powerful that pump is. Having an idea of what Pump Head Pressure is about will help you to converse more easily with a pump manufacturer. If you feel that you can explain this even simpler than this or would like to improve it –please drop us a line.

There are terms which are often used like “pump flow rate” but we are not really discussing flow rate. The flow rate is normally expressed in Litres per Minute , Gallons per min or M3/H . The flow rate has to do with the velocity of the fluid expressed as a  volume over time . The smaller the pipe , the greater the velocity but lesser volume. The volumetric flow rate may also depend on other factors like how dense the fluid is. The more dense the fluid,  the slower it will move.  If you have a pipe full of water and a pipe full of thick oil, the water is going to move more easily than the oil.

Some other  words that might be used for Pump Head Pressure are pressure-head-shut-off  or head-shut-off pressure
Pump manufactures who use the term Head Pressure  are normally referring to a pump’s vertical discharge or vertical lift normally measured in feet of water. When viewing a Pump Manufacturer’s graph you will see that at some point the curved lines flatten off or rather there is no flow rate at this point so it is important to know Head Pressure in case you are buying a pump to perform a  particular task but have mistakenly undersized it.  People do this all the time!

A  good Pump Manufacturer sales technician should be able to help to size a pump that you need from your application if this is something that you do not want to be concerned with. If everyone was expected to do this, there would be no need for a pump service industry. Pump-Manufacturers.com lists pump manufacturers in many locations and they should be able to provide you literature and explanations to help you purchase the correct pump. But here is a simple calculation.  Head (ft.)/2.31 = PSI and PSI x 2.31 = Head (feet) It is equally correct to convert head into pressure and vice versa with the factor .433. Head in feet multiplied by .433 is pressure in PSI, and pressure divided by .433 is head in feet. Mathematically: Head (feet) x .433 = PSI and PSI/.433 = Head (feet) The following way of calculating total head pressure is greatly simplified. It does not take into account frictional resistance ,  exact pipe diameters and other factors.  This article is written for the novice and there are plenty of people in the Pump Manufacturing service industry who have made it a job to help others select pumps and hopefully their pump!  If you do not wish to become a pump expert please contact several of the companies on this website with your application  and see which one is still providing a service. http://www.pump-manufacturers.com