Classification of compressors:
ALTERNATIVE TYPE COMPRESSOR: This type of machine uses a crank-rod system to convert the rotary movement of an axis into the translational movement of a piston or piston. In this way, with each rotation of the actuator, the piston makes a one-way and one-way flow in the direction of the head, establishing a cycle of operation.
ROTARY TYPE COMPRESSOR: The rotary system consists of a roller that rotates in eccentric movement inside a cylinder, forming two chambers (suction and discharge) separated by a vane. The suction and compression of the refrigerant fluid occur at the same time and continuously, providing better performance and lower noise and vibration.
Unlike the alternatives, the rotating compressor housing supports the high pressure discharge gas. The suction gas is drawn directly into the body cylinder, being compressed and then discharged into the compressor housing. Thus, the high pressure, high temperature refrigerant fluid makes the rotating compressor casing warmer.
SCREW TYPE COMPRESSOR: This type of compressor has two screw-type rotors that rotate in the opposite direction, keeping a gear condition between them. The gas penetrates through the suction opening and occupies the intervals between the rotor threads. From the moment that a certain thread is engaged, the gas contained therein is enclosed between the rotor and the walls of the housing. The rotation then causes the gear point to move forward, reducing the space available for the gas and causing it to be compressed. Finally, the discharge opening is reached, and the gas is released.
SCROLL TYPE COMPRESSOR: Scroll compressors like other rotary technologies require few moving parts compared to piston compressors. Due to the low speed of sliding at all points of contact, the precision mechanism and the adjusted tolerances of the scroll elements eliminates the need to use a large volume of oil for this function. The proximity between the spirals also has the advantage of eliminating the spacings and reducing leaks, being possible to create high-performance compressors at the same time that it has less displacement. This is in direct contrast to piston compressors, where the higher leakage ratios (lower yield) are compensated by using larger displacements.
They are silent and low vibration compressors; Its noise level is relatively independent of the gas pulsation and is more associated with its mechanical devices.
CENTRIFUGAL TYPE COMPRESSOR: Constructively, the centrifugal compressor resembles the centrifugal pump. The fluid penetrates through the central opening of the rotor and, by the action of the centrifugal force, moves to the periphery. Thus, the rotor blades impart a high velocity to the gas and raise its pressure. From the rotor the gas is directed to the blades of the diffuser or to a volute (shell formed by very short turns), where part of the kinetic energy is transformed into pressure. In cases where the pressure ratio is low, the compressor can be constructed with a single rotor, although in most machines multi-stage compression is adopted.
