Water pumps are devices that are very familiar to us. However, not everyone knows how to fully understand them or handle the situations and troubleshooting issues that arise during pump operation.
In this article, Thái Khương shares information about water pumps, common situations encountered, and how to address them for our readers.
What Is a Water Pump
A water pump is a device used to move water. Water pumps are among the oldest and most widely used machines, and they exist in many different forms. The shaduf, or shadoof, a very primitive type of pump, is known to have existed since around 2000 BCE.
Pumps can be powered by:
- Human power: hand cranks, foot pedals, moving pistons
- Animal power
- Mains electricity, electric motors
- Battery power
- Solar energy, photovoltaic collectors powering electric motors
- On-site fuel engines: diesel, gasoline; coal-fired steam engines
- Wind energy
Who Invented the Water Pump
The first pump invented by humanity was the shadoof. The Egyptians are credited with this invention, millennia before the Common Era. The shadoof was a bucket tied to a pole or rope, used to raise water from deep wells.
Although this does not precisely describe the operation of a modern pump, it is the earliest historical evidence that humans have always sought devices to help transport water more easily. And while this first pump may seem overly simple by today’s standards, it is worth noting that it appeared only a thousand years into human civilization on the planet.
Types of Water Pumps
After the fall of the great Roman Empire, pump technology stagnated for nearly one and a half millennia. It was not until the Age of Enlightenment that hydraulic science began to receive renewed attention.
It was during this era that the pump was revived, and over the following centuries, new ideas and inventions began flooding the market, all leading to the design of the modern pump.
Below, let us explore the various pump types along with the inventors behind them.
Gear Pump
In 1593, a Frenchman named Nicolas Grollier de Serviere sketched early designs for a gear pump. Later in 1636, a German engineer named Pappenheim invented the deep-tooth, double-rotating gear pump, which is still used for engine lubrication to this day.
Centrifugal Pump
This is one of the most widely used pump types today, and it was invented in the 17th century by Denis Papin, a French inventor. He used straight vanes to discharge water. The centrifugal pump is motor-driven and draws water by creating suction force.
The Savery Pump
In 1698, an inventor named Thomas Avery created a pump that used steam to operate. The steam generated a vacuum, which then drew water upward.
Axial Flow Pump
Since the 1940s, axial flow pumps have been present in water supply services. In addition to this application, axial flow pumps are also widely used in the industrial and commercial sectors.
Submersible Borehole Pump
This type is similar to a centrifugal pump but is primarily used to lift water from deep wells.
Electromagnetic Pump
This type is primarily used in advanced applications such as nuclear reactors. This is because electromagnetic pumps can handle very high temperatures. As a result, they are well suited for applications involving liquid metals and other electrically conductive fluids. They use an electromagnetic force to move fluids.
In addition, many other pump types have been invented from the 1900s to the present, including:
- Submersible pump
- Deep-well turbine pump
- Vertical turbine pump (sealless)
- Lined pump
- Peristaltic pump
- Machine metering pump
- Magnetic drive pump
- Chopper pump
- Circulation pump
- Air-operated double diaphragm pump…
Construction of a Water Pump
Today, water pumps come in many different types. However, they all share a common basic construction dating back to when they were first invented. These components include:
- Drive motor (some pump types use compressed air)
- Pump casing
- Impeller (some pump types have no impeller; instead, they use a diaphragm, as in diaphragm pumps…)
- Suction port and discharge port
Working Principle of Water Pumps
There are many different types of water pumps, including positive displacement pumps and centrifugal pumps, which serve the same function yet operate in different ways.
The core concept of a water pump is to use a motor to convert rotational energy or kinetic energy and transform it into energy for moving fluid (hydrodynamic energy).
A centrifugal pump operates with an impeller; the fluid enters through the rotating impeller and is pushed outward by centrifugal force through the impeller tips. This process increases the velocity and pressure of the fluid and directs it toward the pump outlet.
Positive displacement pumps have an expanding cavity on the suction side and a reducing cavity on the discharge side of the pump. They operate by alternately filling the cavity and then displacing the fluid with each cycle at a constant volume regardless of the pressure or head being used.
Although they share a similar function, the key differences between centrifugal water pumps and positive displacement pumps are: Centrifugal pumps may have variable flow rates depending on the pressure of the head being used. Positive displacement pumps can vary flow rate regardless of system pressure or head. Another important difference is that when the flow rate of a centrifugal pump decreases, viscosity increases, whereas for a positive displacement pump, as flow rate increases, viscosity also increases.
Why Does the Water Pump Have Low Output?
Low pump output is a problem that anyone who has operated a water pump will have encountered. There are many causes for this issue. To resolve it thoroughly, there is no other way than to carry out a general inspection and systematically eliminate possible causes.
Some causes that Thái Khương has encountered and resolved include:
- Weak power supply, voltage drop, or phase loss
- Suction strainer clogged with debris, blocking the suction line
- Issues with the pump casing, typically a damaged impeller or seized pump shaft
- The motor may also be burned out or operating intermittently
The repair approach is not overly difficult. As Thái Khương mentioned above, the key is to carry out a thorough inspection and eliminate causes one by one until the exact fault is identified.
Troubleshooting steps include:
- Check the power supply
- Check motor operation
- Inspect the suction inlet and remove debris
- Inspect the pump casing, perform functional testing; if results are unsatisfactory, contact your supplier or a pump repair service for assistance…
Why Does the Water Pump Fail to Deliver Water?
The causes of a pump completely failing to deliver water are similar to those for low pump output described above. However, this condition is generally considered more severe.
Some causes include:
- Power loss to the pump
- Burned-out motor
- Completely seized pump shaft
- Fully damaged impeller
- Suction inlet completely blocked, with no water suction path
- Water source depleted…
The repair approach is similar to that for low pump output. For more complex pump types such as diaphragm pumps, gear pumps, screw pumps, piston pumps, or vane pumps, it is advisable to engage a professional service to ensure pump performance is properly restored.
Why Does the Water Pump Lose Its Prime?
Loss of prime in a pump is usually related to the suction line. The main causes of this condition are as follows:
- The foot valve is leaking and no longer functions as a check valve
- The suction pipe has a cracked or broken section causing leaks that allow air to enter
- A blown gasket at the connection between the pump head and the piping also causes this condition
The remedy is to review each potential cause and address the issue at the identified point. Recheck, then re-prime with water and run the pump to verify the problem has been resolved.
Why Does the Water Pump Make Loud Noise?
The main causes of a loud water pump can come from 2 sources:
- Noise from the pump casing: In this case, the pump shaft may be grinding, seized, lacking lubrication, or the pump may have run dry at some point. Additionally, a damaged, worn, broken, or chipped impeller also produces loud, abnormal sounds during operation.
- Noise originating from the pump motor: This is usually the first thing the technical team checks, as the pump motor is responsible for the majority of loud water pump noise. The cause may be that internal motor components have deteriorated after extended use, become unstable, and produce a motor hum. A burned winding will also generate abnormal humming. A seized rotor shaft produces very loud and unpleasant grinding sounds. The remedy is to disconnect the power supply and check for shaft play in the motor. Look for a burning smell or black burn marks on the motor. Minor damage may allow the motor to be rewound. If damage is too severe, replacement is recommended.
Applications of Water Pumps
Today, water pumps can be considered an indispensable device, both in daily life and in industrial production. Simply put, without water pumps, how would you have access to water? Water pumps are used to pump water from treatment plants to your home, from wells into storage tanks, and from tanks to faucets for daily use.
In industry, water pumps in general contribute to improving production productivity and creating quality finished products. They enable factories to handle processes that cannot be performed by human effort or any other tool or machine.
Water pumps serve many industries, from heavy industry such as mining and oil and gas, to sectors requiring hygiene and safety standards such as healthcare, pharmaceuticals, and F&B.
Thái Khương has shared detailed information about water pumps for our readers. Thái Khương has been active in this industry for nearly 15 years, and is confident in its ability to supply products and resolve the water pump issues you encounter.
