Chiller is a kind of water cooling equipment, which can provide constant temperature, constant current, constant pressure cooling water equipment. Its working principle is to first inject a certain amount of water into the water tank inside the machine, cool the water through the refrigeration system, and then send the low-temperature cooling water to the equipment to be cooled by the water pump. To achieve the role of cooling. The temperature of the cooling water can be adjusted according to requirements, and the cooling water can be recycled to achieve the purpose of saving water resources. Therefore, chiller is a standard energy-saving equipment.
The cooling principle of industrial chiller: The operation of industrial chiller system is completed by three interrelated systems, including refrigerant circulation system, water circulation system, and electrical automatic control system. Each system is analyzed in detail below!
1. Compressor: The compressor is the core component of the entire refrigeration system and the source of power for refrigerant compression. Its role is to convert the input electrical energy into mechanical energy and compress the refrigerant.
2. Condenser: During the cooling process, the condenser plays the role of outputting heat energy and condensing the refrigerant. After the high-pressure superheated steam discharged from the refrigeration compressor enters the condenser, it absorbs all the heat absorbed during the working process, including the heat absorbed from the evaporator and the refrigeration compressor and in the pipeline, and transfers it to the surrounding medium (water or Air); the high-pressure superheated vapor of the refrigerant condenses back into a liquid. (According to the different cooling medium and cooling method, condensers can be divided into three categories: water-cooled condensers, air-cooled condensers, and evaporative condensers.)
3. Liquid accumulator: The liquid accumulator is installed behind the condenser and is in direct communication with the drain pipe of the condenser. The refrigerant liquid of the condenser should flow unobstructed into the reservoir, so that the cooling area of the condenser can be fully utilized. On the other hand, when the heat load of the evaporator changes, the demand for the refrigerant liquid also changes. At that time, the liquid receiver plays a role of regulating and storing the refrigerant. For small refrigerating device systems, a liquid receiver is often not installed, but a condenser is used to adjust and store the refrigerant.
4. Drying filter: In the refrigeration cycle, it is necessary to prevent the entry of moisture and dirt (oil, iron filings, copper filings), etc. The source of moisture is mainly the trace moisture contained in the newly added refrigerant and lubricant, or due to Moisture from air ingress while servicing the system. If the moisture in the system is not eliminated, when the refrigerant passes through the throttle valve (thermal expansion valve or capillary), sometimes the moisture will freeze to ice due to the decrease in pressure and temperature, which will block the passage and affect the normal operation of the refrigeration device. Therefore, a drying filter must be installed in the refrigeration system.
5. Thermal expansion valve: In the refrigeration system, the thermal expansion valve is both a flow regulating valve and a throttling valve in the refrigeration equipment. It is installed between the drying filter and the evaporator in the refrigeration equipment. Its temperature sensing package It is bandaged at the exit of the evaporator. Its main function is to make high-pressure and normal-temperature refrigerant liquid throttling and reducing pressure when passing through a thermal expansion valve, and turn it into low-temperature and low-pressure refrigerant wet vapor (mostly liquid, a small part is steam) into the evaporator and vaporize in the evaporator. Absorb heat, and achieve the purpose of cooling.
6. Evaporator: The evaporator is a heat exchange device that relies on the evaporation (in fact, boiling) of the refrigerant liquid to absorb the heat of the cooled medium. Its function in the refrigeration system is to absorb heat (or output cooling capacity). In order to ensure that the evaporation process can be carried out stably and continuously, it is necessary to continuously use a refrigeration compressor to extract the evaporated gas to maintain a certain evaporation pressure.
7. Refrigerant: Most industrial chillers used in modern industry use R22 or R12 as refrigerant. Refrigerant is a mobile working medium in a refrigeration system. Its main function is to carry heat and to absorb and release heat when the state changes.
8. Water circulation system: The water circulation system is a pump that draws water from the water tank to the equipment that the user needs to cool. After the heat is taken away by the frozen water, the temperature rises, and then returns to the frozen water tank.
9. Electric appliance automatic control system: Electric appliance automatic control system includes power supply part and automatic control part. The power supply part supplies power to the compressor, fan, water pump, etc. through the contactor. The automatic control part includes temperature controller, pressure protection, time delay, relay, overload protection and other functions to achieve automatic start, stop and protection according to water temperature.
10. Refrigerant circulation system: The liquid refrigerant in the evaporator absorbs the heat in the water and starts to evaporate, and then becomes gaseous and is sucked in and compressed by the compressor (pressure and temperature increase), and then sent to the condenser for high-temperature pressure gaseous refrigeration The refrigerant releases heat through the condenser (air-cooled / water-cooled) and condenses into a liquid. After being throttled and decompressed by a thermal expansion valve (or capillary tube), it becomes a low-temperature and low-pressure refrigerant and enters the evaporator again to absorb the heat in the water. A cyclic process. The refrigerant circulates in this way, continuously taking away the heat in the water, thereby achieving the purpose of cooling water.
Basic composition of refrigeration system
The above ten points are the working principle of Guansheng chiller, detailed analysis of each system in the chiller!
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