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1. Insulation material and moisture-proof layer
A. Library plate: pre-produced, with fixed length, width and thickness, can be selected according to the requirements of the installation of the library body. High and medium temperature cold storage generally choose 10 cm thick plate, low temperature storage and freezing storage generally choose 12 cm or 15 cm thick plate;
B. Polyurethane spray foaming material: this material is sprayed directly in the warehouse to form a polyurethane foam board that does not absorb water and has good thermal insulation, but has high cost.
C. Polystyrene spray foaming material: this material also forms polystyrene board by spraying, which is more water-absorbent than polyurethane board, and has poor thermal insulation, but lower cost.
D. The thermal insulation performance is reduced after the thermal insulation material is damp. Accordingly should add moistureproof layer on both sides of adiabatic board, also can do exterior moistureproof layer only. The moisture-proof layer is usually made of asphalt, asphalt felt, plastic coating, plastic film or metal plate.
2. Refrigeration system
A. Compressor (the most important part) : generally, the small cold storage adopts the fully closed compressor. Semi - enclosed compressor is commonly used in medium - sized cold storage. Semi-closed compressor is used in large cold storage.
B. Evaporator: in general, fan is used as evaporator for high temperature storage, which is characterized by fast cooling speed, but easy to cause water loss of cold collection; Seamless steel tube evaporative discharge tube is mainly used in medium and low temperature cold storage.
C. condenser: the condenser has air cooling, water cooling and air and water combination cooling. Air cooling is limited to small cold storage facilities, while water-cooled condensers can be used in all forms of refrigeration systems.
3. Other accessories: temperature controller, door lock, hinge, handle, etc.