What Is A Foot Valve In A Pumping System?

Is it possible to prime when a pump is installed vertically? Isn’t it going to pump out all the water back to the tank when turned off? This is a general issue as gravity plays the spoilsport. This is the reason why you need to install foot valves in the pumping system to keep up the prime and also prevent damage.

What is a foot valve?

When you are trying to lift the liquid from a lower ground to higher, a foot valve plays a major role in such applications. It is installed at the end of the suction pipe so that the liquid do not return as soon the system is turned off. Even if the storage tank is located at a lower level than the pump, the same problem may occur. In all the situations, foot valve is crucial to stop the flow of the liquid. In the industrial language, it is also called a check valve which is often installed along with a strainer at the opening.

Why is it so crucial?

The check valve is assisted with a spring. Whenever you consider to turn on the pump, the pressure inside it changes and the valve responds immediately after opening. Again the spring system reacts as soon as the pump is turned off. One of the major benefits of foot valve is, it can check the flow of the water if the power (which is needed to operate the pump) fluctuates. Foot valves stop the drainage of fluid out of column and thus, the prime is lost every time the pump is turned off. Remember, foot valve is an important component in positive displacement pumps, especially if it is rotary lobe pump.

What is the role of the strainer?

The strainer’s role is to keep away the debris from the pump especially in the pipeline and in the column of the pump casing. Generally, vertical pumps have tight tolerances. Still, if a small amount of debris enters the system, it can prove to be detrimental for the same.

The strainer also plays an important role in lodging the debris in the foot valve. This results in blocking of the valve at the opening and thus, the fluid in the column stays as it is. This nullifies the point of installing additional valves and keys on the pipes.

Before installing any foot valve in the pumping system, make sure that you determine the type of model from a reputed pump supplier in Ireland.