What Is A Refrigeration Compressor

What Is A Refrigeration Compressor?

1. Concept Introduction

The refrigeration compressor is one of the key components of the vapor compression refrigeration system. A typical vapor compression refrigeration system is shown in the figure. The system consists of a refrigeration compressor 1, a condenser 2, a throttling device 3 and an evaporator 4. The refrigeration compressor inhales the low-pressure refrigerant vapor from the evaporator, compresses it into high-pressure gas in the cylinder, and then discharges it into the condenser to condense into high-pressure liquid. The refrigeration compressor is the power source of the entire refrigeration cycle. For this reason, the compressor is required to have both high reliability and good economy.

Classification of refrigeration compressors

There are many ways to classify refrigeration compressors, mainly the following:

(1) According to the principle of increasing gas pressure, refrigeration compressors are divided into volumetric refrigeration compressors and speed refrigeration compressors.

(2) According to the type of refrigerant, refrigeration compressors can be divided into organic refrigerant compressors and inorganic refrigerant compressors.

(3) According to the sealing method, refrigeration compressors can be divided into three types of compressors: open type, semi-closed type and fully closed type.

(4) According to the different evaporation temperature ranges, refrigeration compressors can be divided into high-temperature, medium-temperature and low-temperature refrigeration compressors.

2. Specific structure of refrigeration compressors

(1) Positive displacement refrigeration compressor: directly compresses the refrigerant vapor in a closed volume with variable volume to reduce its volume, thereby achieving the purpose of increasing the pressure. Positive displacement refrigeration compressors mainly include reciprocating (also known as piston type), screw type, scroll type, rolling rotor type, vane type and rotary vane type.

• Reciprocating refrigeration compressor
• Screw refrigeration compressor
• Scroll refrigeration compressor
• Rotary refrigeration compressor
• Piston refrigeration compressor

(2) Speed ​​refrigeration compressor: The way to increase the pressure of the refrigerant gas is to first increase the kinetic energy of the gas (while the pressure is also increased to some extent), and then convert the kinetic energy into potential energy to increase the pressure. There are two types of speed refrigeration compressors: centrifugal and axial flow. Because the compression ratio of axial flow refrigeration compressors is small and not suitable for refrigeration systems, speed refrigeration compressors generally refer to centrifugal refrigeration compressors.

Centrifugal refrigeration compressor

(3) According to the different sealing methods, refrigeration compressors can be divided into three categories: open type, semi-closed type and fully closed type.