How Does The Water Pump Work?

The water pump uses mechanical and hydraulic principles throughout a piping system to create enough force to drive water.  When the water is moving fast in the pump, it creates low pressure at the intake, hence creating a vacuum. As the water is moving toward the outlet from a low-pressure side, the water outlet experiences a higher pressure and, in turn, pushes the water with that force. 

There are various types of water pumps, but we are going to discuss a few of them. It is essential to discuss them so that people can understand the drawback and advantages of each one.  We will be looking at centrifugal water pumps and the positive displacement water pumps in detail. Below is how each of these types of water pump works. Read to be knowledgeable! 

How Does The Water Pump Work

Centrifugal Water Pumps 

This is a type of water pump that is power-driven by a device known as an impeller. It involves many blades that direct water via the pump. These water pumps come in several kinds which comprises submersible, standard and trash model.  With these pumps, all sorts of liquids can be pumped with low-viscosity. Also, these pumps work fine with thin liquids and provide high flow rates.

How Centrifugal Water Pumps Works 

The device called impeller lies at the heart of a centrifugal water pump. It has a series of curves that can be fitted with shroud plates. This water pump is regarded as the most efficient. With its impeller immersed in water, there is no doubt the water pump will work its magic.

Once you turn on your water pump, the impeller will rotate, making the fluid around it rotate. This rotation conveys centrifugal force to the water particles, which is the source behind the water moving radially out. 

At the impeller’s discharge sides, both pressure and kinetic energy will be expected to increase since rotational mechanical energy is moved to the fluid. Water is displaced at the water pump’s suction port, causes low pressure to be induced.  This low-pressure aids in sucking the water into the system once more and thus creates a cyclical process. 

With this kind of water pump, the impeller is usually fitted inside a casing.  The water moving out will be stored inside it and will move in the matching way of spinning the impeller to the water exit.

 It is worthy of knowing the field of the casing.  It has an increasing area along the movement direction, which will aid in housing the water moving in. Plus, it helps in minimizing exit flow velocity. This, therefore, increases static pressure, which is crucial in overcoming the resistance of the pumping system. 

There is one problem linked to a standard centrifugal water pump, and that is air.  When the pump comes across air, it becomes air-bound; hence it becomes hard to pump air than water. This means that the pump cannot work as required in forcing out water with pressure. The pump that performs at its best will be filled with water with no traces of air. 

Considerations For Centrifugal Water Pumps 

These types of pumps are applicable in numerous applications such as building and water systems. They are used to offer water supplies for facilities and matched with pneumatic systems where the no-suction lift is needed. These water pumps’ primary function is to pump water from boreholes in people’s residences and upsurge water pressure in intake lines. Also, they provide a nonstop pressure supply for fireguard systems. 

Self -Priming Water Pumps

This type of pump solves the problem associated with a standard centrifugal water pump, but how? By preventing air binding. This kind of pump aims to mix the water with air to make a fluid pumped typically. Once this process is complete, the pump removes the air and moves the water like a standard centrifugal pump. 

How Self -Priming Water Pumps Works 

Unlike the standard centrifugal water pump, this kind of pump has a water reservoir built into the unit, which aids it to rid the pump and suction line of air by recirculating water within the pump throughout the priming process. 

The water reservoir can be located in front of the impeller or above the impeller. This depends on where the manufacturer of the water pump decides to place the impeller. Sometimes, a pump’s ability to “self-prime” depends on its capability to hold water after the first prime. 

It is crucial to know that the pump ought to have water in the casing to function. It is sensible never to run such a pump without water because it can be dangerous and might lead to seal failure. 

Positive Displacement Water Pumps 

Their designs are two, the rotary water pumps or reciprocating water pumps. They use mechanical energy to transfer water, and that what makes it different from centrifugal water pumps. When the displacement is on the forward stroke, it is said to be single acting. 

How Positive Displacement Water Pumps Works 

This water pump is double acting, given that it displaces water both on the forward and return stroke. It can deliver very high pressures. The pressure can be more than the design pressure, and so a relief valve is required to protect the pump. Also, these pumps are self-priming because the suction and delivery are positively separated throughout pumping. However, an external priming connection from the pump ought to be available to reduce wear and make sure there is a quick starting of the pump. 

They usually function in a circular motion and displace a constant liquid quantity with every pump shaft revolution. This is accomplished by pumping mechanisms moving in that manner to expand volumes to permit water to go into the pump. 

The water pump keeps these volumes till the geometry makes the elements move to reduce the volume and ensure the liquid is ejected out. The removal of these elements within the pumps separates the suction from the released liquid, making them critical for effective operation. 

Considerations For Positive Displacement Water Pumps 

These pumps are competitive because of their capability to eliminate air from the lines. Also, they are efficient as it deals with high-viscosity fluids. The main downside of these pumps is that they require slight clearance between the revolving pump and the unit’s external edge. 

How To Choose The Pump?

One should consider the following factors:

Material– The pump material ought to be weather-resistant. The quality water pumps are generally made with lightweight aluminum casting. These kinds of materials ensure that it lasts a long time. It’s good to choose a water pump with an extended warranty because it is made from quality materials. 

Type Of Fuel And Motor – The fuel and motor of the pump should be gas, hydraulic, diesel-electric motor. 

Head–  The head should be suitable for proposed applications.

Power– the power of the pump mainly comprises the flow rate and horsepower.

Usage– what do you intend to use the water pump for should be among the factors to take into consideration. For example, you require a submersible water pump for deep wells as opposed to a jet pump. 

Applications Of Water Pumps 

They are used for dewatering reasons reducing the downtime from enormous rain actions.  These pumps’ typical applications comprise boost applications, circulation of hot water, wells, building, fire systems protection, sump pits, etc. 

These pumps are an excellent addition to our life; they make a possible enormous variety of agricultural, industrial, and household tasks.  However, the type of water pumps out there is so adaptable and abundant that choosing the correct pump suitable for your requirement is challenging. 

How Does The Old-Fashioned Water Pump Work?

The foot valve opens on the piston’s top stroke, and suction brings water into the pump head. The piston’s valve opens and permits water to move above the piston on the pistons’ bottom stroke. Once the subsequent upstroke of the piston is attained, water is discharged out of the outlet. 

What Is The Function Of The Water Pump?

A car water pump’s function is to shove coolant via the car’s engine block, hoses, and radiator to ensure the engine is heated away from the system. Most often, the water pump drives off the crankshaft or crankshaft pulley. 

How Can I Run A Water Pump Without Electricity?

You can use solar energy to run. Most solar-powered water pumps are long-lasting, effortless to install, cost-effective, and need minimum maintenance compared to the standard water pumps. The installed pump can last for up to 20 years. 

How Do You Get Rid Of Water Without A Pump?

Here is the process:

1. Put one end of a water hose in the pool 

2. Place the other end of the hose to where you desire the water to the gutter 

3. Drain off the water out of the pool by putting your mouth on the end of the hose and suck it more times as possible until water comes out. 


As seen above, there are a few water pumps that someone can opt to use and how each one works. Always choose the right one based on the water source. 

Leave a Comment