What are the working principles, types and applications of centrifugal pumps?

A centrifugal pump is a device that uses centrifugal force to transport liquid from a low-pressure area to a high-pressure area. It is a common fluid transport tool in modern industry and is widely used in water treatment, chemical industry, petroleum, construction and other fields. Unlike other types of pumps, centrifugal pumps mainly accelerate the liquid by rotating the impeller and force the liquid to flow through its centrifugal force to complete the liquid transportation.
The core component of a centrifugal pump is the impeller. When the motor drives the pump shaft to rotate, the impeller rotates at high speed, and the liquid flows into the impeller from the pump inlet. As the impeller rotates, the liquid gains energy under the action of the impeller and gradually accelerates. The liquid is thrown to the outer wall of the pump body under the action of centrifugal force and eventually flows out through the pump outlet. In this process, the kinetic energy of the liquid is converted into pressure energy, thereby realizing the transportation of the liquid.
The working principle of a centrifugal pump can be summarized as three processes: "intake, acceleration, and discharge". First, the liquid enters the impeller through the pump inlet; second, the liquid is accelerated by the impeller and converted into kinetic energy; finally, the liquid is discharged through the pump outlet at a higher pressure.
Centrifugal pumps can be divided into many types according to their structure and purpose. The following are several common types of centrifugal pumps:
Single-stage centrifugal pump
Single-stage centrifugal pumps are the most common type, with only one impeller inside the pump body. It is suitable for low to medium head (i.e. the output pressure of the pump) and is usually used in water treatment, agricultural irrigation, liquid transportation and other occasions.

Multistage centrifugal pump
Multistage centrifugal pumps are composed of multiple impellers, each of which further accelerates the liquid to provide a higher head. It is mainly used in high-head and high-pressure requirements, such as boiler feed pumps, fire pumps, etc.
Self-priming centrifugal pump
Self-priming centrifugal pumps can automatically discharge air after the pump is started, and can absorb liquid for continuous transportation. Its application scenarios include mud transportation, oil fields and other special liquid transportation.
Magnetic drive centrifugal pump
Magnetic drive centrifugal pumps use magnetic force instead of traditional mechanical couplings for driving, thereby avoiding the problem of pump shaft sealing and reducing the risk of leakage. Commonly used in the transportation of corrosive liquids, hazardous chemicals and other occasions.
Centrifugal pumps have become the preferred equipment for liquid transportation due to their simple structure, high efficiency and wide application. Its main advantages include:
High efficiency
Centrifugal pumps provide powerful energy conversion through the rotation of the impeller, and can achieve large flow and pressure in a short time.
Strong adaptability
Centrifugal pumps can adapt to a variety of liquid transportation and are suitable for a variety of media such as water, chemical liquids, oils and mud.
Simple structure and easy maintenance
Centrifugal pumps have a relatively simple structure, are easy to disassemble and clean, and have low maintenance costs.
However, centrifugal pumps also have some challenges:
Cavitation problem
If the pressure at the suction port of the centrifugal pump is too low, it may cause the liquid to evaporate in the pump, forming bubbles and bursting, causing damage to the pump body and reduced efficiency.
The matching problem of flow and head
The flow and head of the centrifugal pump are mutually restricted. Excessive head may lead to reduced flow and affect work efficiency.
Centrifugal pumps are widely used in various industries, especially in the fields of liquid transportation and water treatment. The following are some typical applications of centrifugal pumps:
Water treatment industry
Centrifugal pumps are used in sewage treatment, drinking water transportation and various water circulation systems. Its high efficiency and stability make it an important part of water treatment plants.
Chemical Industry
In the chemical industry, centrifugal pumps are often used to transport various chemical liquids, solvents and acid-base substances. Its corrosion resistance is essential for chemical processes.
Petroleum Industry
In the process of oil extraction and refining, centrifugal pumps are used to transport crude oil, petroleum products and chemical additives.
Construction Industry
Centrifugal pumps are also widely used in the construction field, especially in air conditioning cooling systems and pump rooms, for water supply and drainage systems in buildings.
Centrifugal pumps have become an indispensable and important equipment in modern industry due to their high efficiency, simplicity and versatility. With the continuous development of technology, the performance and application scope of centrifugal pumps are also constantly improving, and they will play a greater role in more fields in the future.