What Is A Chiller:
Today, LNEYA refrigeration manufacturer will explain the working principle of the chiller. In the refrigeration industry, it is divided into air-cooled chillers and water-cooled chillers. According to the compressor, it is divided into screw chillers and scroll chillers. In terms of temperature control, it is divided into low-temperature industrial chillers and normal temperature chillers. , The temperature of the normal temperature unit is generally controlled within the range of 0 degrees -35 ° C. The temperature control of the low temperature unit is generally from 0 degrees to -120 °C (our equipment can reach as low as -150 °C). Because chillers are widely used, the requirements for chillers in various industries are not exactly the same. Its working principle is a multi-functional machine, through compression or heat absorption refrigeration cycle. The chiller consists of four main components: compressor, evaporator, condenser, and expansion valve, so as to achieve the cooling or heating effect of the unit. The following is a brief introduction to the working principle of the chiller.
The Basic Components Of The Refrigeration System
Compressor: The compressor is the core component of the entire refrigeration system and the source of power for refrigerant compression. Its function is to convert the input electrical energy into mechanical energy and compress the refrigerant.
Condenser: During the refrigeration process, the condenser plays the role of outputting heat energy and condensing the refrigerant. After the high-pressure superheated vapor discharged from the refrigeration compressor enters the condenser, all the heat absorbed during the working process, including the heat absorbed from the evaporator and the refrigeration compressor and in the pipeline, is transferred to the surrounding medium (water or air) to take away. The high-pressure superheated vapor of the refrigerant is re-condensed into a liquid. (According to the cooling medium and cooling method, condensers can be divided into three categories: water-cooled condensers, air-cooled condensers, and evaporative condensers.)
Liquid accumulator: The liquid accumulator is installed after the condenser and is directly connected to the drain pipe of the condenser. The refrigerant liquid of the condenser should flow into the liquid receiver unimpeded, 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 of the refrigerant liquid also changes accordingly, and the liquid accumulator plays the role of adjusting and storing the refrigerant at that time. For small refrigeration equipment systems, the liquid receiver is often not installed, but the condenser is used to adjust and store the refrigerant.
Filter drier: 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 lubricating oil, or due to the maintenance system. Moisture brought by the ingress of air. If the water in the system is not removed, when the refrigerant passes through the throttle valve (thermal expansion valve or capillary), the water will sometimes freeze into ice due to the drop in pressure and temperature, blocking the channel and affecting the normal operation of the refrigeration device. Therefore, filter driers must be installed in the refrigeration system.
Thermal expansion valve: The thermal expansion valve is not only a flow control valve in the refrigeration system, but also a throttle valve in the refrigeration equipment. It is installed between the drying filter and the evaporator in the refrigeration equipment. at the outlet of the evaporator. Its main function is to throttle and depressurize the high-pressure and normal-temperature refrigerant liquid when it flows through the thermal expansion valve, and turn it into a low-temperature and low-pressure refrigerant wet vapor (mostly liquid, a small part of which is vapor) into the evaporator and vaporize in the evaporator. Absorb heat to achieve the purpose of cooling and cooling.
Evaporator: The evaporator is a heat exchange device that relies on the evaporation (actually 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). In order to ensure that the evaporation process can be carried out stably and lastingly, the evaporating gas must be continuously pumped out by the refrigeration compressor to maintain a certain evaporation pressure.
Refrigerant: Most industrial chillers used in modern industry use R22 or R12 as refrigerant. Refrigerant is the flowing working medium in the refrigeration system. Its main function is to carry heat, and to absorb and release heat when the state changes.
Water Circulation System
The water circulation system is a water pump that pumps water from the water tank to the equipment that the user needs to cool. The chilled water takes away the heat and then the temperature rises, and then returns to the chilled water tank.
Electrical automatic control system:
The electrical automatic control system includes the power supply part and the automatic control part.
The power supply part supplies power to compressors, fans, water pumps, etc. through contactors.
The automatic control part includes thermostat, pressure protection, delay device, relay, overload protection, etc. to achieve automatic start and stop according to the water temperature, protection and other functions.
Industrial Chiller Cooling Characteristics
With the rapid development of modern industrial technology, in order to improve production efficiency, improve product quality, and reduce production costs, the requirements for temperature control in the production process are getting higher and higher.
The general water cooling method (that is, natural water and water tower cooling methods) cannot achieve the purpose of high-precision and high-efficiency temperature control, because both natural water and water tower cooling are inevitably affected by natural temperature, and the water temperature in winter is low in summer. . If the air temperature is 30°C, it is almost impossible for the water temperature to reach 10°C, so it is extremely unstable to control in this way.
The chiller is completely different from the general water cooling equipment, because the chiller has a completely independent refrigeration system, which will never be affected by the temperature and the environment. The purpose of high-efficiency temperature control. The chiller is equipped with an independent water circulation system, and the water in the chiller is recycled, which can save a lot of water.