Working principle of screw air compressor (detailed explanation)

Screw air compressor

screw air compressor is a kind of air compressor, there are two kinds of twin screw and single screw. The invention of the double is more than ten years later than the single, and the design of the double screw air compressor is more reasonable and advanced. The double overcomes the shortcomings of single imbalance and bearing vulnerability, and has the advantages of long life, low noise and more energy saving. After the technology matured in the 1980 s, its scope of application was expanding day by day.

basic structure

usually referred to as the screw compressor refers to the twin screw compressor.

The basic structure of the screw compressor: in the body of the compressor, a pair of spiral rotors meshing with each other are arranged in parallel.

A rotor with convex teeth outside the pitch circle is usually called a male rotor or a male screw. A rotor with concave teeth in the pitch circle is called a female rotor or a female rotor.

Generally, the male rotor is connected with the prime mover, and the male rotor drives the female rotor to rotate.

the last pair of bearings on the rotor achieves axial positioning and takes up the axial forces in the compressor. The cylindrical roller bearings at both ends of the rotor enable the rotor to achieve radial positioning and withstand the radial forces in the compressor.

At both ends of the compressor body, orifices of a certain shape and size are respectively opened. One is for suction, called the intake port; the other is for exhaust, called the exhaust port.

Maintenance costs are low

High performance and high efficiency

air compressor equipment-screw air compressor adopts high-capacity compression components, its rotor outer circle speed is low and the best oil injection is achieved, achieving high efficiency and high reliability. Until 2012, the manufacturer's design ensures that the system temperature and compressed air temperature are extremely low. All components are guaranteed to achieve the best cooling effect and maximum service life.

Driving concept

air compressor equipment-Screw air compressors drive the compression assembly at the optimum speed for the application through an efficient transmission system. No maintenance at all during normal operation. It has the advantages of maintenance-free, high reliability and high efficiency.

Air compressor equipment-screw air compressor original compressor design saves unnecessary maintenance costs. All components are designed for long life, and the large size of the inlet filter, oil filter and fine separator ensure the best compressed air quality. All oil filters and all types of separator components within the 22kW (30hp) are centrifugal open and close, further reducing maintenance time.

Built-in intelligent control

to reduce operating costs, precise operational control is essential. All screw compressors are equipped with an intelligent control system, and the control menu is easy to use.

Working principle

Working Schematic Diagram

1 Inspiratory process

the screw air compressor has no intake and exhaust valve group, and the intake only depends on the opening and closing of an automatic regulating valve. When the tooth groove space of the main and auxiliary rotors is transferred to the opening of the intake end of the casing, the space is the largest. At this time, the tooth groove space under the rotor communicates with the free space of the intake port. Because the air in the tooth groove is completely discharged during exhaust, when the exhaust is finished, the tooth groove is in a vacuum state, and the outside air is sucked in and flows into the tooth groove of the main and auxiliary rotors along the axis, when the air fills the entire tooth groove, the air inlet side end of the rotor is turned away from the air inlet of the casing, and the air between the tooth grooves is closed. The above is the "suction process".

2 closed and conveying process

at the end of suction, the main and auxiliary rotor teeth are sealed with the casing, and the air in the tooth groove no longer flows out, that is, the "closed process". The two rotors continue to rotate, their tooth peaks and tooth grooves coincide at the suction end, and the coincident surface gradually moves to the exhaust end, thus forming a "gas transmission process".

3 Compression process and fuel injection process

during the transportation process, the anastomosis surface gradually moves to the exhaust end, that is, the tooth groove space between the anastomosis surface and the exhaust port gradually decreases, the air in the tooth groove is gradually compressed, and the pressure gradually increases, that is, the "compression process". At the same time of compression, lubricating oil is also injected into the compression chamber and mixed with air due to the effect of pressure difference.

4 Exhaust process

when the end face of the exhaust port of the rotor communicates with the exhaust port of the casing (the gas pressure is the highest at this time), the compressed gas starts to exhaust until the matching surface of the tooth peak and the tooth groove moves to the end face of the exhaust end of the casing. At this time, the tooth groove space between the matching surface of the two rotors and the exhaust port of the casing is zero. The "exhaust process" is completed ". At the same time, the length of the tooth groove between the rotor and the housing inlet reaches the longest, thus starting a new compression cycle.