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The freezer refers to a mechanical apparatus for changing the pressure change of the refrigerant gas by a compressor to achieve a high temperature refrigeration. The compressor used is different from a general air compressor due to its use conditions and compressed working media. According to the difference in the structure and working principle of the  freezer, it is similar to the air compressor or is divided into several different forms such as piston type, screw, centrifugal type. Freezer is one of the most important components in compressed refrigeration equipment. The  freezer is connected by a compressor, a condenser, an evaporator, a dry filter, and an expansion throttle. The inside of the injective amount of refrigerant is controlled by the electrical appliance to control the compressor operation and achieve refrigeration heat transfer. the goal of.

The  freezer  has a water-cooled, air-cooled type.

Water-cooled refrigeration effect is better, but it is necessary to cool water, the air cooling is flexible, no cooling water is required, suitable for use in water shortage or need to be used. The working medium of the refrigerator is a refrigerant that delivers heat tasks in the refrigeration system. Commonly used refrigerants are: fluoridone, ammonia, bromide, chloromethane, etc., wherein the fluoridon is different from its gasification temperature and chemical molecular formula. Fluorine 11 (R-11), fluorine 12 (R-12), fluorine 13 (R-13), fluorine 21 (R-22), fluorine 113 (R-113), fluorine 114 (R-114), fluorine 142 (R-142), etc. The refrigerant can be used for low pressure (less than 0.3-0.3 MPa), the evaporation temperature is greater than 0 ° C), medium pressure (condensation temperature 0--50 ° C) and high pressure (condensation pressures) More than 2 MPa) Refrigeration system with low temperature (evaporation temperature is less than -50 ° C).