Working principle of air compressor

Air compressor principle

the air compressor (English: air compressor) is the main body of the air source device. It is a device that converts the mechanical energy of the prime mover (usually an electric motor) into gas pressure energy. It is a pressure generating device for compressed air. It uses the principle of air compression. A machine that makes compressed air that exceeds atmospheric pressure.

we can also watch the shanghai granklin group production of water lubricated air compressor video, to better understand the oil free air compressor is how to work:

according to the different ways of compressed air, air compressors are usually divided into two categories, one is volumetric type, the other is power type, and can be divided into the following forms according to their different structures:

Principle of 1. screw air compressor

screw compressor is a helical rotary displacement compressor, which is one of the most widely used displacement compressors in the world.

The basic structure of the screw compressor is shown in the figure below. In the body of the compressor, a pair of helical rotors meshing with each other are arranged in parallel. The thick tooth profile is usually called the male rotor or male screw; the thin tooth profile is called the female rotor or female screw. Generally, the male rotor is connected with the prime mover, and the male rotor drives the female rotor to rotate. The ball bearing on the exhaust end of the rotor enables the rotor to achieve axial positioning and bear the axial forces in the compressor. At both ends of the compressor body, orifices of a certain shape and size are respectively opened. One for suction, called the suction orifice; the other for exhaust, called the exhaust orifice. (Generally, intake from the top and exhaust from the bottom).

As shown in the figure below, the working cycle of the screw compressor can be divided into three processes: suction (1), compression (2)(3) and exhaust (4). As the rotor rotates, each pair of intermeshing teeth successively completes the same duty cycle. The volume occupied by the gas sealed in the volume between the teeth also decreases with the movement of the teeth, resulting in an increase in pressure, thereby realizing the compression process of the gas. When the volume between the teeth is connected to the exhaust hole, the exhaust process begins.

Principle of 2. single screw air compressor

the working principle of the single screw air compressor is through the interactive rotation of the two star wheels, because their configuration is symmetrical, thus dividing the space into two, and respectively compressing the gas in them. The balance force is symmetrical. The biggest feature of the single screw machine is that the manufacturer has to solve the problem that the star wheel will wear too much at high speed and high temperature between the plastic star wheel and the screw in order to ensure that the gas production will not drop too fast.

Principle of 3. piston air compressor

the working principle of the piston air compressor is to use the crank connecting rod mechanism to convert the rotary motion of the prime mover into the linear reciprocating motion of the piston, and use the automatic opening and closing of the intake and exhaust valves to suck in, compress and discharge the gas, because it is used The method is relatively backward, and the gas will contain a lot of oil. This kind of equipment is not suitable for industries that require high gas accuracy, secondly, there are also problems such as large noise, pulse of gas and easy bad of the host.

4. sliding vane compressor air compressor principle

sliding vane compressors are driven directly at lower speeds using conventional technology. The rotor is a continuous running component, with several grooves cut along the length, in which a sliding plate that can slide on the oil film is inserted.

The rotor rotates in the stator of the cylinder. During the rotation, the centrifugal force throws the sliding vane out of the groove to form a separate compression chamber. The rotation reduces the volume of the compression chamber and the air pressure increases continuously. Oil is used to control the heat generated by compression, and then the air compression is completed.

Because the method used is relatively backward, the gas will contain a lot of oil. At this time, what is needed is an oil and gas separator, which can be filtered clean before it can be put into production. This kind of equipment is not suitable for high gas accuracy requirements. In the industry, there are also problems of high noise and high maintenance cost of the main engine.

Principle of 5. centrifugal compressor

the working principle of the centrifugal compressor is that when the air enters the machine, the impeller will rotate quickly, and the gas will enter the diffuser to gradually complete the compression. Its most significant advantages are energy saving, large displacement, low failure rate, low operating cost, and oil-free compressed air. It is the first choice for users with more than 100 cubic meters of gas.

Product range of 6. general purpose compressors