The working principle of the ice making system of the ice maker and the change of the refrigerant

The ice maker adopts a refrigeration system, and the equipment (machine) that produces ice after passing through a certain device with a water carrier is called an ice maker.

The role of ice is divided into three types: one is cooling, the other is food, and the third is artificial scenes for viewing.

Take the snowflake ice maker as an example. Its working principle is: after the compressor of the ice maker starts and runs, it undergoes suction-compression-exhaust-condensation (air-cooled)-throttling (capillary tube). )-Drying (filter drying)-Evaporation (evaporate at a low temperature of -10 to -18 degrees in the evaporator that wraps the ice drum to absorb heat and vaporize). The tap water at room temperature continuously condenses into an ice layer on the inner surface of the colder ice churn. When the ice layer of the ice maker has condensed to a certain thickness, the slowly rotating screw rod connected by the ice stirring motor will squeeze the crushed ice out of the ice outlet. After the temperature is set, the heating solenoid valve is switched on and the ice is often flushed in the form of a heat pump to prevent the screw shaft from being frozen and realize continuous ice making.

Refrigerant R134A

The refrigerant of the ice maker is the working medium that completes the refrigeration cycle in the refrigeration equipment, also called the working fluid of the ice maker.

The requirements for the refrigerant of the ice maker are: low price, non-toxic, good cooling effect, stable physical and chemical properties. Its characteristics:

Under standard atmospheric pressure, the boiling point should be low. Generally, it should be below -20°C. The condensing pressure is low. Generally, the condensing pressure does not exceed 1.17MPa-1.47MPa. It can reduce the pressure strength of the container, reduce leakage, and reduce the power consumption of the compressor.

The latent heat of evaporation is large. That is, the cooling capacity per unit volume is large, and the circulation capacity is small. Conducive to reducing the scale of the refrigeration system.

Stable chemical properties and low corrosiveness. Especially it has no chemical reaction with lubricating oil.

Non-toxic, non-flammable, non-explosive, low viscosity, good heat transfer performance, safe and reliable, etc.

This snowflake ice maker uses R-134a refrigerant, the Chinese name is tetrafluoroethane, and the molecular formula is CH2FCF3. Since R-134a belongs to HFC substances (non-ODS substances Ozone-depletingSutances), the ODP value is zero, so it does not destroy the ozone layer. It is an environmentally friendly refrigerant recognized and recommended by most countries in the world, and it is also the current mainstream environmentally friendly refrigerant. All new-generation centrifugal and screw ice machines are designed around R-134a.

In the refrigeration cycle of the ice maker refrigerant, the gaseous refrigerant is compressed into a high-pressure gas through the compressor, and is condensed into a normal temperature, high-pressure liquid through the air-cooled condenser, and the pressure is reduced by the capillary tube Then it changes from a normal temperature, high pressure liquid to a low pressure, low temperature liquid, which is vaporized in the evaporator to absorb heat and then flows back to the compressor to continue the cycle.