Refrigeration equipment refers to the equipment mainly used for the refrigeration of crew food, the refrigeration of various cargoes and the air conditioning of cabins in summer. It is mainly composed of compressor, expansion valve, evaporator, condenser, accessories and pipelines. According to the working principle, it can be divided into compression refrigeration equipment, absorption refrigeration equipment, steam injection refrigeration equipment, heat pump refrigeration equipment and electrothermal refrigeration equipment. The most common application on ships is compression refrigeration equipment. The heat of the object and its surroundings is removed through the working cycle of the equipment, resulting in and maintaining a certain low temperature state. The refrigerants used are mainly Freon and ammonia, and Freon is the most used. However, due to the damaging effect of Freon on the atmospheric ozone layer, it has begun to be restricted by environmental protection regulations. Ammonia and other new refrigerants are being reused and trial-produced.
Refrigeration equipment is a device in which a refrigerator is combined with a facility that uses cold energy. Refrigeration units are designed and constructed to efficiently use cold energy to refrigerate food or other items; to perform performance tests and scientific research experiments on products at low temperatures; to implement certain cooling processes in industrial production, or to perform air conditioning. When the item is cooled or frozen, a certain amount of heat will be released, and the enclosure structure of the refrigeration device will also introduce a certain amount of heat when it is in use. Therefore, in order to maintain the low temperature conditions in the refrigeration unit, it is necessary to install a refrigerator to continuously remove the heat, or to absorb the heat by melting ice or sublimation of dry ice.