What are the advantages of screw compressors?

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Working principle of screw air compressors: 1. Intake process: The intake port on the suction side of the screw compressor must be designed in such a way that the compression chamber can draw in air adequately. Screw compressors do not have separate intake and exhaust valve assemblies; instead, air intake is regulated by the opening and closing of a control valve. As the rotors rotate, the grooves between the main and auxiliary rotors reach their maximum volume when they align with the intake port openings. At this point, the air in these grooves is in contact with the free air outside. During exhaust, all the air in these grooves is expelled, leaving them in a vacuum state. When they align with the intake port again, external air is drawn in and flows axially into the grooves of the main and auxiliary rotors. When the air fills the entire tooth groove, the inlet-side end face of the rotor moves away from the inlet opening of the housing, and the air between the tooth grooves is thus trapped. 2. Sealing and conveying process: At the end of air intake, the tooth tips of the main and auxiliary rotors come into contact with the casing, thereby sealing off the air within the tooth grooves and preventing it from flowing out. The two rotors continue to rotate, with their tooth peaks and tooth grooves aligning at the intake side, and this alignment point gradually moves toward the exhaust side. 3. Compression and fuel injection process: During transportation, the meshing surfaces gradually move toward the exhaust end; in other words, the gap between the meshing surfaces and the exhaust port gradually decreases. The gas within this gap is progressively compressed, resulting in an increase in pressure. This is what happens. Meanwhile, due to the pressure difference, lubricating oil is also sprayed into the compression chamber to mix with the air there. 4. Exhaust process: When the meshing surfaces of the rotors come into alignment with the exhaust port of the casing (at this point the pressure of the compressed gas is at its highest), the compressed gas begins to be expelled. This continues until the meshing surfaces between the teeth move to the exhaust end face; at that point, the space between the meshing surfaces of the rotors and the tooth grooves at the exhaust port becomes zero, thus completing the exhaust process. At the same time, the length of the tooth grooves between the meshing surfaces of the rotors and the intake port reaches its maximum, and the intake process resumes