Refrigeration Oil and Working Principles of Positive Displacement Refrigeration Compressors

Refrigeration oil is a special lubricating oil for refrigeration compression equipment, and it is an important component that determines and affects the refrigeration function and effect of the refrigeration system. During the operation of the refrigeration compressor, low temperature is obtained by the reduced-pressure evaporation of the refrigerant, while refrigeration oil lubricates the working parts of the refrigeration equipment. There are various types of refrigeration compressors, which can be divided into positive displacement refrigerators, absorption refrigerators, steam jet refrigerators, and semiconductor refrigerators according to their working principles. There are many classification methods for positive displacement refrigerators, and the following three main classification methods are introduced. Reciprocating refrigeration compressors usually convert the rotational motion of the prime mover into the reciprocating motion of the piston through a crankshaft-connecting rod mechanism, raising the refrigerant vapor from low pressure to high pressure and making it circulate continuously in the refrigeration system. Screw refrigeration compressors achieve the purpose of changing the cylinder volume through the rotation of the screws, thereby realizing the circulation process of the refrigerant in the system. Centrifugal refrigeration compressors usually change the cylinder volume through the rotation of the impeller, raising the refrigerant vapor from low pressure to high pressure and making it circulate continuously in the refrigeration system.​

A Brief Analysis of the Operation Logic and Lubrication Guarantee of Core Components in Refrigeration Systems​

The above titles are formulated from two perspectives: core content summary and technical logic extension. They not only clarify the role of refrigeration oil but also highlight the working characteristics of the three types of positive displacement refrigeration compressors, which are suitable for technical popularization or professional teaching materials.