Working principle structure diagram of screw air compressor

Working principle structure diagram of screw air compressor 1. The basic structure and working principle of screw air compressor The commonly known screw compressor refers to the twin screw compressor. The basic mechanism of screw compressor: In the body of the compressor, a pair of intermeshing spiral rotors are arranged in parallel. Usually the rotor with convex teeth outside the pitch circle is called the male rotor or male screw. The rotor with concave teeth in the pitch circle is called the female rotor or female rotor. Generally, the male rotor is connected to the prime mover, and the female rotor drives the female rotor to rotate. The last pair of bearings on the rotor achieve axial positioning and bear the axial force in the compressor. Cylindrical roller bearings at both ends of the rotor enable the rotor to achieve radial positioning and withstand radial forces in the compressor. At both ends of the compressor body, openings of a certain shape and size are opened respectively. One for intake, called the air intake, and the other for exhaust, called the exhaust. working principle: The working cycle of screw compressor can be divided into three processes: intake, compression and exhaust. As the rotor rotates, each pair of intermeshing teeth sequentially completes the same working cycle. 1. Intake process: When the rotor rotates, the space of the tooth groove of the male and female rotors is the largest when it is turned to the opening of the intake end wall. At this time, the space of the rotor groove is communicated with the air inlet. The gas is completely discharged. When the exhaust is completed, the tooth groove is in a vacuum state. When it is turned to the air inlet, the external gas is sucked into the tooth groove of the Yin and Yang rotor in the axial direction. When the gas fills the entire tooth groove, the end face of the rotor intake side is away from the air inlet of the casing, and the gas in the tooth groove is closed. 2. Compression process: At the end of the suction of the Yin-Yang rotor, the tip of the Yin-Yang rotor will be closed with the casing, and the gas will no longer flow out in the tooth groove. The engaging surface gradually moves toward the scheduling end. The space of the tooth groove between the engagement surface and the exhaust port gradually becomes smaller, and the gas in the tooth groove is compressed by the compression pressure. 3. Exhaust process: When the meshing end face of the rotor turns to communicate with the exhaust port of the casing, the compressed gas begins to be discharged until the tooth surface of the tooth tip and the tooth groove moves to the end face of the schedule. The tooth groove space between the meshing surface and the exhaust port of the casing is 0, that is, the exhaust process is completed. get on. It can be seen from the above working principle that the screw compressor is a volumetric gas compression machine with a working volume for rotary motion. The compression of the gas depends on the change in volume, and the change in volume is achieved by a pair of rotors of the compressor rotating in the casing. Characteristics of screw compressor: As far as the principle of increasing gas pressure is concerned, screw compressors are the same as piston compressors, and both belong to positive displacement compressors. In terms of the movement form of the main components, it is similar to the centrifugal compressor. Therefore, the screw compressor has the characteristics of the above two types of compressors. Advantages of screw compressor: 1. High reliability: The screw compressor has few parts and no wearing parts, so it operates reliably and has a long service life. The interval between overhauls can reach 40,000-80,000 hours. 2. Convenient operation and maintenance: the operator does not need professional training, and can realize unattended operation. 3. Good power balance: the screw compressor has no unbalanced inertial force, the machine can work smoothly at high speed, and it can be operated without foundation. 4. Strong adaptability: The screw compressor has the characteristics of forced gas transmission, and the discharge volume is almost not affected by the discharge pressure, and it can ensure higher efficiency in a wide range. 5. Multi-phase mixed transmission: The rotor tooth surface of the screw compressor actually has a gap, so it can resist liquid impact, and can send liquid-containing gas, dust-containing gas, and easily polymerized gas. Disadvantages of screw compressors: 1. High cost: The rotor tooth surface of the screw compressor is a space curved surface, and it needs to use a special tool and add an expensive special equipment for processing. In addition, the machining accuracy of the screw compressor cylinder also has high requirements. 2. Not suitable for high-pressure occasions: Due to the limitations of rotor stiffness and bearing life, screw compressors are intelligently used in the medium and low pressure ranges, and the exhaust pressure generally cannot exceed 3.0Mpa. 3. Can not be made into miniature: screw compressors rely on gap seal gas, currently only when the volume flow is greater than 0.2m3/min, the screw compressor has superior performance. Workflow of twin screw air compressor The air is filtered through the air intake filter to remove dust or magazines in the atmosphere, and then enters the compressor main unit through the air intake control valve. During the recompression process, it is mixed with the injected cooling lubricating oil. Into the oil and gas separation tank, at this time, the oil gas compressed and discharged through collision, interception, and gravity, most of the oil medium is separated, and then enters the oil and gas fine separator for secondary separation to obtain compressed air with little oil content. When the air is compressed to the specified pressure value, the minimum pressure valve is opened, the compressed air is discharged to the cooler for cooling, and finally sent to the use system.