How the pump works: principle of operation, characteristics and types of devices - Setafi

In this article, you will find out how many types of pumps there are, what are the most popular types of water / gas pumps, the design of piston pumps, the principle of operation of vortex, centrifugal, rotary pumps.

The principle of operation of the pump depends on its type, so you first need to understand the types of pumps. In total there are about three thousand of them. They differ in design, mode of action, mechanism, method of supplying / dispensing water. All types of pumps can be divided into two large groups: volumetric and dynamic.

In positive displacement pumps, liquid/gas is pushed out due to a change in the volume of the inner chamber. The most popular example is piston pumps. In them, the piston moves to the end of the chamber, the water after it is drawn into the open chamber, after which the piston begins to reverse - the volume of the chamber decreases, the pressure of the water increases, and it flies out of branch pipe.

In dynamic pumps, the volume of the chamber does not decrease - water is pushed out from the impact of the pump elements on it. For example, centrifugal and vortex.

Here are the main types of pumps:

• Piston
• winged
• Lamellar-rotary
• Gear with external gearing
• Gear with internal gearing
• Cam with sickle-shaped rotors
• impeller
• Sinus
• screw
• Peristaltic
• Vortex
• Centrifugal

Below we will analyze the 4 most popular types of pumps, tell you about the characteristics of different types of pumps, the design of pumps and the principle of their operation.

Rotary pumps

The main feature of rotary pumps is that they do not have a valve. This role is performed by the rotors, which hermetically shut off the water supply.

The principle of operation of rotary pumps

Water enters from one side of the pump, exits from the opposite. Inside are two cut half-disk. There is a space between their width and the wall of the pump, and it is filled with water. The motor drives the half-discs. They are designed so as not to touch each other when rotating. A portion of water is sealed and moved by the rotor, after which the two chambers with water are connected, the rotors compress them, because of this, the pressure rises, the water is pushed out of the pump. The rotors are put back in place and the cycle repeats.

Advantages of rotary models:

• High performance
• No vibration
• Do not make noise
• Can pump thick, viscous and hot media
• You can supply water in the opposite direction without removing the pump
• Water is self-priming
• No need for refrigeration
• No lubrication needed

Minuses:

• Expensive repairs
• High price
• Cannot work with solid inclusions

Rotary models are most often used in industry, mainly in the oil sector, but also in chemical, marine and food plants. Often, rotary pumps put utilities in a central heating system.

Piston pumps

Piston models of pumps are popular in everyday life and industry. They have two valves. They are located in places where the body is connected to the pipes for supplying / discharging water. The body of such devices is a cylinder. It contains a piston that fits snugly against the walls of the cylinder. A tube is connected to the piston, which connects it to the connecting rod. The second is connected to the crank. It is located on one side of the disk.

The principle of operation of piston pumps

The motor rotates a disk with a crank. When the crank moves away, it pulls the connecting rod, that tube, the piston tube. This increases the volume of the chamber into which water enters. Water fills the chamber, the disk rotates. The crank pushes the connecting rod, tube and piston. The piston presses on the water, the pressure rises, and the water is pushed out of the pump.

The main advantages of piston pumps:

• Reliable - there is almost nothing to break in them
• Easy Assembly
• No lubrication needed
• No need for refrigeration

Minuses:

• Low efficiency
• Low performance

Most often, piston pumps can be found in the food industry and in domestic heating systems. Often they are used in the chemical field due to the fact that they can work with aggressive and explosive substances.

Centrifugal pumps

Centrifugal models are dynamic pumps. They push water out with the help of blades. The design of centrifugal pumps: a wheel with a small number of blades is attached to the axis of rotation, the entire the mechanism is in a metal case, water enters it directly into the center of the wheel, it comes out of the side tubes.

The principle of operation of centrifugal pumps

Water is sucked into the device through the supply pipe. The flow is divided into two parts - up and down. The motor moves the bladed wheel. The blades move a portion of the water to the outlet tube and push it out.

Advantages of centrifugal pumps:

• High performance
• High efficiency (97%)
• Work with large volumes of water
• Powerful
• No pulsation in the water supply

Minuses:

• Must be completely filled with water - otherwise they may jam
• Sensitive to air bubbles
• Expensive repairs

Install centrifugal models in the industry, they work with large volumes of water, powerful and with high efficiency; less often installed in everyday life, as they are designed for intensive and large work. With the help of centrifugal pumps, water is pumped from shallow sources (up to 10 meters).

vortex pumps

One of the most popular models. Their design and principle of operation are similar to centrifugal counterparts. The design of vortex pumps: a disk with a large number of blades / blades is attached to the end of the motor axis, the mechanism is located in the housing, where water enters and exits from opposite sides.

The principle of operation of vortex pumps

Water is supplied from one side. The blades, rotated by the motor, move the streams of water - they suck, seal and move the portions. So a vortex is created inside the pump chamber, which enhances the flow. Water is pushed out by a whirlwind and blades from the opposite side. At the outlet, the water pressure increases by 5-7 times.

Advantages of vortex pumps:

• Reliable
• Work with solid inclusions in water
• Can pump aggressive, gaseous and hot liquids
• Silent
• Small dimensions
• Low price
• Large outlet water pressure

Minuses:

• Cannot pump viscous and thick liquids
• Poor performance
• low power
• Low efficiency (no more than 45%)

Such devices are used mainly in everyday life - where high fluid pressure is needed at the outlet. For example, in heating systems, lifting water from deep wells (up to 20 meters).