Basic Structure and Working Principle of Cold Storage Rooms

I. Refrigeration Principle

The refrigeration principle of a cold storage room is to use a refrigeration unit to remove heat from the interior of the storage unit, thereby lowering the internal temperature to achieve cooling and freezing purposes.

The core of a cold storage unit is the refrigeration unit. This device achieves the refrigeration process by circulating refrigerant. The refrigerant is a special substance that absorbs heat through low-temperature evaporation and then releases heat through high-temperature condensation. The refrigeration unit transfers heat by circulating the refrigerant, thereby achieving cooling in the cold storage.

Unit

II. Basic Components of the Refrigeration System The four main components of a refrigeration system are the compressor, condenser, expansion valve, and evaporator.

1. Refrigeration System – Compressor The compressor draws low-temperature, low-pressure gas from the evaporator, compresses it into high-temperature, high-pressure gas, and sends it to the condenser. Common compressor types include scroll compressors, reciprocating compressors, and screw compressors.

Compact size, low noise, suitable for small cold storage facilities within 1,000 cubic meters, but expensive.

ZR144

[Reciprocating Compressor]

Low cost, wide range of applications, but has many wear-prone parts and higher noise levels.

[Screw Compressor]

Durable components, easy to maintain, used for large cold storage and blast freezers, high cost.

2. Refrigeration System – Condenser The refrigerant releases heat and becomes liquid in the condenser, maintaining a constant pressure equal to the compressor discharge pressure (high pressure). The following are three types of condensers:

[Evaporative Condenser]

Suitable for large cold storage rooms

Suitable for large and medium cold storage facilities in areas with water availability.

Suitable for small cold storage facilities in water-scarce areas

3. Refrigeration System – Condensing Unit

6HP1

4. Refrigeration System – Evaporator The refrigerant vapor-liquid mixture absorbs heat and evaporates into gas within the evaporator, maintaining a constant pressure equal to the suction pressure (low pressure).

Defrosting Methods:

Electric defrosting: medium-high temperature cold storage

Water defrosting: low-temperature cold storage

Hot gas defrosting: medium-low temperature cold storage

III. Basic Components of a Cold Storage Unit A cold storage unit mainly consists of a refrigeration system, an insulated storage body, and a control panel.

1. Refrigeration System The four main components of the refrigeration system are the compressor, condenser, expansion valve, and evaporator.

2. Insulated Cold Storage Body (Double-sided color steel polyurethane sandwich panel)

High-temperature cold storage (above 0°C): 100mm thick insulation panels;

Medium-low temperature cold storage (-20~0°C): 150mm thick insulation panels;

Low-temperature cold storage (below -20°C): 200mm thick insulation panels.

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3. Control Box

Temperature controller (standard cold storage), PLC touch screen (multi-functional cold storage standard, optional for standard cold storage)