Industrial chiller and refrigeration principle - industrial chiller principle - chiller refrigeration process flow chart

Industrial chiller and refrigeration principle - industrial chiller principle - chiller refrigeration process flow chart

The chiller is a water cooling device that provides constant temperature, constant current, and constant pressure cooling water equipment. The working principle is to first inject a certain amount of water into the water tank of the machine, and then cool the water through the refrigeration system, and then the low-temperature cooling water is sent to the equipment to be cooled by the water pump, and the chilled water takes the heat away and then the temperature rises and then flows back to the water tank. , to achieve the effect of cooling. The cooling water temperature can be adjusted automatically according to requirements, and long-term use can save water. Therefore, the chiller is a standard energy-saving device.

Cooling principle of industrial chillers The operation of industrial chiller systems is through three interrelated systems: refrigerant circulation system, water circulation system, and electrical automatic control system.
Refrigerant circulation system:
The liquid refrigerant in the evaporator absorbs the heat in the water and begins to evaporate. A certain temperature difference is formed between the final refrigerant and the water, and the liquid refrigerant is completely evaporated to a gaseous state and then sucked and compressed by the compressor (pressure and temperature increase). The gaseous refrigerant absorbs heat through the condenser (air-cooled/water-cooled), condenses into a liquid, and is throttled by a thermal expansion valve (or capillary tube) to become a low-temperature low-pressure refrigerant to enter the evaporator, completing the refrigerant circulation process.
Basic composition of the refrigeration system Compressor: The compressor is the core component of the entire refrigeration system and the source of refrigerant compression. Its function is to convert the input electrical energy into mechanical energy to compress the refrigerant.
Condenser: The condenser acts to output thermal energy and condense the refrigerant during cooling. After the high-pressure superheated steam discharged from the refrigeration compressor enters the condenser, all the heat absorbed in 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 The air is taken away; the refrigerant high pressure superheated vapor recondenses into a liquid. (Depending on the cooling medium and cooling method, the condensers can be divided into three categories: water-cooled condensers, air-cooled condensers, and evaporative condensers.)
Reservoir: The reservoir is installed after the condenser and is in direct communication with the drain of the condenser. The refrigerant liquid in the condenser should flow unimpeded 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 required amount of the refrigerant liquid also changes, and at that time, the reservoir functions to regulate and store the refrigerant. For small refrigeration systems, the reservoir is often not installed, but a condenser is used to regulate and store the refrigerant.
Drying filter: moisture and dirt (oil, iron filings, copper scraps) must be prevented from entering the refrigeration cycle. The source of moisture is mainly the newly added refrigerant and trace water contained in the lubricating oil, or due to the maintenance system. The moisture that comes when the air enters. If the moisture in the system is not cleaned out, when the refrigerant passes through the throttle valve (thermal expansion valve or capillary), the moisture will solidify into ice due to the pressure and temperature drop, which will block the passage and affect the normal operation of the refrigeration unit. Therefore, a dry filter must be installed in the refrigeration system.

Thermal expansion valve: The thermal expansion valve is both a flow regulating valve in the refrigeration system and a throttle valve in the refrigeration device. It is installed between the drying filter and the evaporator in the refrigeration device, and its temperature sensing package is bandaged. At the exit of the evaporator. Its main function is to reduce the pressure of the high-pressure normal temperature refrigerant liquid when flowing through the thermal expansion valve, and become a low-temperature low-pressure refrigerant wet steam (mostly liquid, a small part is steam) enters the evaporator and vaporizes in the evaporator. It absorbs heat and achieves the purpose of cooling and cooling.
Evaporator: An evaporator is a heat exchange device that relies on the evaporation (actually boiling) of a 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 a stable and long-lasting evaporation process, the vaporized gas must be continuously withdrawn by a refrigeration compressor to maintain a certain evaporation pressure.
Refrigerants: Most industrial chillers used in modern industry use R22 or R12 as refrigerant. Refrigerant is a working fluid in a refrigeration system. Its main function is to carry heat and achieve heat absorption and heat release when the state changes.
water circulatory system:
The water circulation system is a pump that draws water from the water tank to the equipment that the user needs to cool. The chilled water takes the heat away and the temperature rises, and then returns to the chilled water tank.
Electrical control system:
The electrical control system includes a power supply section and an automatic control section.
The power supply part supplies power to the compressor, fan, water pump, etc. through the contactor.
The automatic control part includes the functions of temperature controller, pressure protection, delay device, relay, overload protection, etc., which can automatically start and stop according to water temperature, and protect.
Chiller working principle diagram

Industrial chiller cooling characteristics and application industrial chiller cooling characteristics Today, with the rapid development of modern industrial technology, in order to improve production efficiency, improve product quality, and reduce production costs, temperature control requirements in temperature control during production are becoming higher and higher.
Generally, water cooling (that is, natural water and water tower cooling methods) cannot achieve high precision and high efficiency to control temperature, because natural water and water tower heat are inevitably affected by natural temperature, and winter water temperature is high at summer. . If the temperature is 30 ° C, it is almost impossible to achieve a water temperature of 10 ° C, so control in this way is extremely unstable.
The chiller is completely different from the general water cooling equipment because the chiller has a completely independent refrigeration system, which is never affected by temperature and environment. The water temperature is adjusted within the range of 5 °C to 30 °C, so that high precision can be achieved. The purpose of high temperature control. The chiller has an independent water circulation system, and the water in the chiller is recycled, which can save a lot of water.
Industrial chiller applications Industrial chillers are widely used in industrial production processes, such as:
Plastic industry: Accurately control the mold temperature of various plastic processing, shorten the cycle of beer and plastic, and ensure the stability of product quality.
Electronics industry: Stabilize the molecular structure inside the production line of electronic components, improve the qualification rate of electronic components, and apply it to the ultrasonic cleaning industry to effectively prevent the damage caused by the volatilization and volatilization of expensive cleaning agents.
Electroplating industry: control plating temperature, increase the density and smoothness of plating parts, shorten plating cycle, improve production efficiency and improve product quality.
Machinery industry: control the pressure oil temperature of the oil pressure system, stabilize the oil temperature and oil pressure, prolong the oil quality use time, improve the efficiency of mechanical lubrication and reduce wear.
Construction industry: The chilled water for concrete is used to make the molecular structure of concrete suitable for the purpose of construction, and effectively enhance the hardness and toughness of concrete.
Vacuum coating: Control the temperature of the vacuum coating machine to ensure the high quality of the plated parts.
Food industry: used for high-speed cooling after food processing to adapt to packaging requirements. There is also a temperature for controlling the fermented food.
Chemical fiber industry: Freeze and dry air to ensure product quality.