Working principle of a spiral chiller

The screw chiller is called the screw chiller because the key component, the compressor, adopts the screw type. The unit is made of gas refrigerant in the state of the evaporator; after being adiabatically compressed by the compressor, it reaches a high temperature and high pressure state. The compressed gas refrigerant is cooled and condensed by isobaric pressure in the condenser, becomes a liquid refrigerant after being condensed, and then expands to a low pressure through a throttle valve to become a gas-liquid mixture. Among them, the liquid refrigerant at low temperature and low pressure absorbs the heat of the cooled substance in the evaporator and becomes a gaseous refrigerant again. The gaseous refrigerant re-enters the compressor through the pipeline to start a new cycle. These are the four processes of the refrigeration cycle and the main working principles of the screw chiller. The principle flow of the screw chiller is divided into air-cooled and water-cooled: Figure 1: The principle flow chart of the air-cooled screw chiller.

Principle: A Screw chiller is named a screw chiller because the key component, the compressor, uses a screw type. The refrigerant that comes out of the unit from the evaporator is a gas, and after being adiabatically compressed by the compressor, it becomes a state of high temperature and high pressure. The compressed gas refrigerant is cooled and condensed by isobaric pressure in the condenser, becomes a liquid refrigerant after being condensed, and then expands to a low pressure through a throttle valve to become a gas-liquid mixture. Among them, the liquid refrigerant at low temperature and low pressure absorbs the heat of the cooled substance in the evaporator and becomes a gaseous refrigerant again. The gaseous refrigerant re-enters the compressor through the pipeline to start a new cycle. These are the four processes of the refrigeration cycle. It is also the main working principle of the screw chiller.

pneumatic fitting
Compared with the scroll type, the power of the screw chiller is relatively large, and it is mainly used in central air conditioning systems or large-scale industrial refrigeration (1). Twin screw refrigeration compressors (twin screw compressors) are a kind of energy-adjustable oil-injection compressor. Its three continuous processes of air intake, compression, and exhaust are realized by a pair of intermeshed male and female rotors in the body that produce periodic volume changes when they rotate. Generally, the male rotor is an active rotor, and the female rotor is an active rotor. The rotor is a driven rotor. Main components: double rotors, body, main bearing, shaft seal, balance piston, and energy adjustment device The capacity is 150% stepless adjustment or two- or three-stage adjustment, and the oil pressure is used to increase or decrease the load. Conventional use: both radial and axial bearings are rolling bearings; the open type is equipped with an oil separator, oil storage tank, and oil pump; and the closed type is for differential pressure oil supply for lubrication, oil injection, cooling, and piston movement for adjusting the capacity of the drive slide valve.

Compression principle: Inhalation process: The gas enters the volume between the teeth of the male and female rotors through the suction port. Compression process: When the rotor rotates, the volume between the teeth of the male and female rotors is connected (a V-shaped space). Due to the mutual engagement of the teeth, the volume gradually decreases and the gas is compressed. Exhaust process: The compressed gas moves to the exhaust port to complete the working cycle. (2) A single-screw refrigeration compressor (single-screw compressor) uses the combination of an active rotor and two star wheels to generate compression. Its three continuous processes of suction, compression, and exhaust are generated periodically when the rotor and star wheel rotate. The volume change is achieved. The number of rotor teeth is six, and the star wheel has eleven teeth. The main components are a rotor, two star wheels, the body, the main bearing, and the energy adjustment device. The capacity can be adjusted from 10% to 100%. And a three- or four-stage adjustment. Compression principle: Inhalation process: gas enters the rotor tooth slot through the suction port. With the rotation of the rotor, the star wheel enters the state of meshing with the rotor tooth slot in turn, and the gas enters the compression chamber (rotor tooth). (The enclosed space is formed by the surface of the groove, the inner cavity of the casing, and the tooth surface of the star wheel.)