Refrigeration equipment is a combination of refrigerator and facilities that use cold energy. Refrigeration equipment is designed and built to effectively use cold energy to refrigerate food or other items. It is mainly composed of compressor, expansion valve, evaporator, condenser, accessories and pipeline. According to the working principle, it can be divided into compression refrigeration equipment, absorption refrigeration equipment, steam jet refrigeration equipment, heat pump refrigeration equipment and electric heating refrigeration equipment. It can be used in refrigerator, cold storage, refrigerated truck and other application fields. The radiation of general refrigeration equipment is very small, which is harmless to human body.

Second, the working principle and composition of refrigeration equipment

1. compressor: the compressor is the core component of the whole refrigeration system and the power source of refrigerant compression. Its function is to convert electric energy input into mechanical energy, suck, compress and transport refrigerant vapor, thus driving the cycle.

2. Condenser: In the refrigeration process, the condenser plays the role of outputting heat energy and condensing refrigerant. After the high-pressure superheated steam discharged from the refrigeration compressor enters the condenser, all the heat absorbed in the working process is transferred to the surrounding medium (water or air), including the heat absorbed from the evaporator, refrigeration compressor and pipeline. Refrigerant is condensed into liquid again under high pressure.

3. Dry filter: water and dust must be prevented from entering the refrigeration cycle. The water mainly comes from a small amount of water contained in newly added refrigerant and lubricating oil, or from the air entering during system maintenance. If the water in the system is not excluded, when the refrigerant passes through the throttle valve (thermal expansion valve or capillary), due to the drop of pressure and temperature, water will sometimes freeze into ice, blocking the channel and affecting the normal operation of refrigeration equipment. Therefore, it is necessary to install dry filter in refrigeration system.

4. Throttle valve: The thermal expansion valve (or capillary) is installed in the refrigeration equipment between the drying filter and the evaporator, and the thermal expansion valve is wrapped at the outlet of the evaporator. Its main function is to throttle and decompress the high-pressure room-temperature refrigerant liquid when it flows through the thermal expansion valve, and transform it into low-temperature and low-pressure refrigerant wet vapor (mostly liquid, with a small amount of vapor) which enters the evaporator to evaporate and absorb the heat in the evaporator, thus achieving the purpose of refrigeration.

5. Evaporator: Evaporator is a kind of heat exchanger, which absorbs the heat of cooling medium by evaporation (actual boiling) of refrigerant liquid. Its function in the cooling system is to absorb heat. In order to ensure a stable and lasting evaporation process, the evaporation gas must be continuously pumped in by the refrigeration compressor to maintain a certain evaporation pressure.

6. Refrigerant: Most industrial coolers used in modern industry use R22 or R407C as refrigerant. Refrigerant is the working medium flowing in refrigeration system. Its main function is to carry heat and realize heat absorption and release when the state changes, and it can also be seen in daily life fields such as pesticides and refrigerators.