A cold storage evaporator is an evaporator used in refrigeration equipment such as cold storage. Its principle is that a low-temperature and low-pressure liquid refrigerant vaporizes and absorbs heat on one side of the evaporator's heat transfer wall, thereby cooling the medium on the other side of the heat transfer wall. The cooled medium is usually water or air. Cold storage evaporators can be divided into two categories: The first type: the air is used as the Natural convection evaporative cold storage pipes, such as the wall pipes and top pipes widely used in cold storage, which are generally of the tube type, single row coil pipe, double row coil pipe, double row U-shaped pipe or four row U-shaped pipe type. The second type: cold air fans with forced air flow often adopt measures such as increasing the heat transfer temperature difference, adding fins to the heat transfer tube, or increasing the air flow rate to improve heat transfer performance. Air cooler evaporator Advantages: The cold air fan mainly relies on convective heat transfer, which is easy to construct and compact in structure. It occupies small space in the cold storage and has little impact on the usage space of the cold storage. There is no requirement for the load bearing on the top of the warehouse, which is common in the assembly cold storage and small Freon cold storage. High heat exchange efficiency, reduced use of materials, reduced costs, forced circulation of air by fans, and faster cooling speed in cold storage. Defrosting is convenient and easy to control, capable of automatic control, easy to operate, and easy to manage. Generally, copper tubes and aluminum fins are used in the market, which have high pressure resistance, strong corrosion resistance, and are not easy to leak. Disadvantages: Due to the forced circulation of the fan, the air flow in the cold storage is fast, and the food in the cold storage is easy to air dry, resulting in high drying consumption of inventory goods. Moreover, the fan itself consumes electrical energy, and the evaporator also needs to defrost frequently. Most small and medium-sized cold storage rooms use electric heating wires to heat the capacity for frost. This periodic defrosting operation of the cold air fan not only causes energy waste, but also causes an increase in the temperature inside the warehouse. evaporative cold storage pipes Advantages: The advantage of aluminum exhaust is that it has an advantage in cold storage capacity compared to a fan, without the need for a fan, and is more energy-efficient. Moreover, the dry consumption of food is low, and the pressure resistance of the exhaust pipe is high. Disadvantages: It occupies a large space and, in some cases, affects the usage area. It mainly relies on radiation heat transfer and does not require a fan. The cooling process is slower than that of a fan, and the defrosting cycle is longer after frost formation, usually twice a year. Defrosting can be done by sweeping frost...

1. Before operation, check whether the sealant pad of the vacuum pump is damaged, and the vacuum gauge is reset to zero. Combine the fluorinated tube, vacuum gauge and vacuum pump. 2. Unscrew the nut at the fluorine filling port from the valve, and screw the fluorine filling pipe onto the fluorine filling port. Turn on the vacuum meter, and then turn on the vacuum pump power switch to start vacuuming. The vacuum degree of the normal system should be below - 756 mmHg (- 0.1 Mpa). The vacuum pumping time shall be determined according to the size of the refrigeration system and the size of the vacuum pump. 3. After the evacuation operation, close the three-way valve of the meter, slightly open the valves of the large and small pipes of the air conditioner to prevent air backflow, quickly remove the fluorine filling pipe and vacuum gauge, and fully open the valve again.

1  Effect of nitrogen on refrigeration system First of all, we should know that nitrogen is a non-condensable gas. The so-called non-condensable gas means that the gas circulates with the refrigerant in the system, does not condense with the refrigerant, and does not produce refrigeration effect. The existence of non-condensable gas will do great harm to the refrigeration system, which is mainly manifested in the increase of system condensation pressure, condensation temperature, bitzer compressor exhaust temperature and power consumption. Nitrogen enters the cold room evaporator and cannot evaporate with refrigerant; It will also occupy the heat exchange area of the cold room evaporator, making the refrigerant unable to fully evaporate and reducing the refrigeration efficiency; At the same time, too high exhaust temperature may lead to the carbonization of lubricating oil, which will affect the lubrication effect, and in serious cases, burn down the refrigeration compressor motor. 2 Effect of oxygen on refrigeration system Oxygen and nitrogen are also non-condensable gases. We have analyzed the hazards of non-condensable gases above, and we will not repeat here. However, it is worth noting that compared with nitrogen, if oxygen enters the refrigeration system, there are still these hazards: 2.1. Oxygen in the air will react with the refrigerant oil in the refrigeration system to produce organic substances, and finally form impurities, which will enter the refrigeration system, causing dirty and blocking and other adverse consequences. 2.2. Oxygen, refrigerant, water vapor, etc. are prone to produce chemical reactions that form acids and oxidize the refrigerant oil. These acids will damage all components of the refrigeration system and the insulation layer of the motor; At the same time, these acid products will remain in the refrigeration system. At first, there is no problem. Over time, the bitzer compressor will eventually be damaged. The following figure illustrates these problems well. 3 Effect of other gases (water vapor) on refrigeration system The water vapor affects the normal operation of the refrigeration system, and the solubility in Freon liquid is the smallest, and gradually decreases with the decrease of temperature. The most intuitive effects of water vapor on the refrigeration system are as follows: 3.1. There is water in the refrigeration system, and the first influence is the throttling structure. When the water vapor enters the throttling mechanism, the temperature drops rapidly and the water reaches the freezing point, causing ice formation, blocking the small through-holes of the throttling structure, and causing ice blockage. 3.2. The water vapor of the corroded pipeline enters the refrigeration system, and the water content of the system increases, causing corrosion and blockage of the pipeline and equipment. 3.3 Produce sludge deposits. In the process of compressor compression, water vapor will encounter high te...

The refrigeration cycle system consists of four basic components: compressor, condenser, evaporator and expansion valve. 1. Bitzer Compressor: Inhale the steam in the evaporator to maintain its low temperature and low pressure; Compress high pressure and high temperature steam. Why compress? Because the refrigerant needs to be recycled. If it is not compressed, it shall be directly discharged into the condenser. The normal temperature is higher than the boiling point temperature of the refrigerant, and cannot be cooled and condensed into liquid. 2. Condenser: Cooling the high-temperature and high-pressure steam discharged from the compressor into liquid; The heat released is taken away by water or air. It can be divided into three types: water-cooled, air-cooled and water-air mixed cooling. The condenser of cold storage mostly adopts fin-coil structure. In order to improve the heat exchange efficiency, aluminum alloy fins are often pressed into various shapes to increase the heat exchange area. 3. Throttle device: When the refrigerant fluid passes through a small hole, a part of the static pressure changes into the dynamic pressure, the flow rate increases sharply, and becomes turbulent flow. The fluid is disturbed, the friction resistance increases, and the static pressure decreases. 4. Evaporator: Evaporate liquid into gas; Absorb heat. Since the fins of the evaporator will continuously produce condensate and hinder the flow of air, the fin spacing of the evaporator is larger than that of the condenser. In addition, hydrophilic treatment (hydrophilic aluminum foil) should be carried out on the surface of the evaporator fins to reduce the surface tension of the condensate and increase the cross-sectional area of the air flow.

Dear customer, The Spring Festival is coming, in order to let everyone have a happy and peaceful Spring Festival. In 2022, with the joint efforts of all departments, the company mainly produces air cooled condensers, air cooled evaporators and condensing units, with a total output value of more than 90 million dollars. Thank customers and suppliers for their support and suggestions. In 2023, our company will make greater efforts to serve customers. After study, it is decided that KITDOO Refrigeration Company will take a rest during the Spring Festival, and the specific schedule is as follows: The production department will take a total of 20 days off from January 12, 2023 to January 31, 2023. The product was officially produced on February 1. The sales department will have a total of 11 days off from January 18, 2023 to January 28, 2023. Accept customer orders on January 29. The After-sales Technical Department normally answers customer calls. Finally, I wish our colleagues, customers and suppliers a happy Spring Festival.

1. Refrigerant leakage: After the refrigerant leaks in the system, the cooling capacity is insufficient, the suction and exhaust pressures are low, and the intermittent airflow sound much larger than usual can be heard at the expansion valve. There is no frost or a small amount of floating frost on the evaporator. If the expansion valve hole is enlarged, the suction pressure still does not change greatly. After the shutdown, the equilibrium pressure in the system is generally lower than the saturation pressure corresponding to the same ambient temperature. 2. Excessive charging of refrigerant after maintenance: The amount of refrigerant charged in the refrigeration system after maintenance exceeds the capacity of the system, and the refrigerant will occupy a certain volume of the condenser, reduce the heat dissipation area, and reduce the cooling effect. The suction and exhaust pressure are generally higher than the normal pressure value, the cooler unit is not frosted solidly, and the cooling in the warehouse is slow 3. There is air in the refrigeration system: the air in the refrigeration system will reduce the refrigeration efficiency. The obvious phenomenon is that the suction and exhaust pressures increase (but the exhaust pressure has not exceeded the rated value), and the compressor of condensing unit outlet to the condenser inlet The temperature increases significantly. Due to the presence of air in the system, the exhaust pressure and exhaust temperature increase. 4. Low compressor efficiency: The low efficiency of the refrigeration compressor of condensing unit refers to the fact that the actual exhaust volume decreases and the refrigeration capacity decreases accordingly when the working conditions remain unchanged. This phenomenon mostly occurs in compressors that have been used for a long time. The wear and tear of the compressors are large, the matching clearance of each component is large, and the sealing performance of the air valve is reduced, resulting in a decrease in the actual exhaust volume. 5. The frost on the surface of the evaporator is too thick: the long-term use of the cold storage evaporator should be defrosted regularly. If it is not defrosted, the frost layer on the evaporator pipeline will accumulate and thicken. When the entire pipeline is wrapped into a transparent ice layer, It will seriously affect the heat transfer, causing the temperature in the warehouse to fall below the required range. 6. There is refrigerated oil in the evaporator pipeline: During the refrigeration cycle, some refrigerated oil remains in the evaporator pipeline. After a long period of use, if there is a lot of residual oil in the evaporator, it will seriously affect its heat transfer effect. , the phenomenon of poor cooling occurs. 7. The refrigeration system is not smooth: due to the poor cleaning of the refrigeration system, after a period of use, the dirt gradually accumulates in the filter, and some meshes are blocked, which reduces t...

1. Compressor: It plays the role of compressing and driving the refrigerant in the refrigerant circuit, and is the power of the refrigeration system. 2. Condenser: It is one of the main heat exchange equipment in the refrigeration system of cold storage. Its function is to cool and condense the superheated vapor of the high-temperature refrigerant discharged from the compressor of the assembled cold storage into high-pressure liquid. 3. Evaporator: The liquid refrigerant evaporates at low pressure and low temperature, absorbs the heat from the freezer and evaporates, and turns into a gaseous refrigerant. The gaseous refrigerant is sucked into the compressor and compressed, and then discharged into the condenser to discharge heat. Basically, the principle of the evaporator and the condenser is the same, the difference is that the former absorbs heat into the storehouse, and the latter exhausts heat to the outside. 4. Liquid storage tank: store Freon storage tank to ensure that the refrigerant is always in a saturated state. 5. Solenoid valve: The first is to prevent the high-pressure part of the refrigerant liquid from entering the evaporator when the compressor is stopped, to prevent the low-pressure from being too high when the compressor is started next time, and to prevent the compressor from liquid shock. Second, when the temperature of the cold storage reaches the set value, the thermostat will act, the solenoid valve will lose power, and the compressor will stop when the low pressure pressure reaches the set value. When the electricity is turned on, the compressor starts when the low pressure pressure rises to the compressor start setting value. 6. High and low pressure protector: to prevent high pressure and low pressure from being too low to protect the compressor. 7. Thermostat: It is equivalent to the brain of the cold storage that controls the opening and stopping of refrigeration, defrosting, and the opening and stopping of fans. 8. Dry filter: filter impurities and moisture in the system. 9. Oil pressure protector: ensure that the compressor has enough lubricating oil. 10. Expansion valve: The high-pressure refrigeration liquid at the outlet of the expansion valve is rapidly expanded and evaporated, and the heat in the air is absorbed through the tube wall for cold and heat exchange. 11. Oil separator: its function is to separate the lubricating oil in the high-pressure steam discharged from the refrigeration compressor to ensure the safe and efficient operation of the device. According to the principle of oil separation by reducing the airflow speed and changing the airflow direction, the oil particles in the high-pressure steam are separated under the action of gravity. Generally, when the airflow velocity is below 1m/s, the oil particles with a diameter of more than 0.2mm contained in the steam can be separated. There are four types of oil separators commonly used: washing type, centrifugal type, packing type and filter type. 12. ...

Cold storage is usually divided into four temperatures: high temperature, medium and low temperature, low temperature, and ultra-low temperature. Different ingredients require different temperatures. A. High temperature cold storage The high temperature cold storage is what we call the cold storage cold storage. Adhere to the temperature is usually around 0 ° C, and air cooler unit with a cooling fan. B. Medium and low temperature cold storage The medium and low temperature cold storage is the high temperature freezing cold storage, the temperature is usually within -18°C, and it is mainly used to store meat, water commodities and commodities suitable for this temperature range. C, low temperature cold storage Low-temperature cold storage, also known as freezing storage, freezing cold storage, usually the storage temperature is about -20°C~-30°C, and the freezing of food is completed by air cooler or special freezing equipment. D. Ultra-low temperature cold storage Ultra-low temperature cold storage, ≤-30 °C cold storage, is mainly used for quick-frozen food and special purposes such as industrial experiments and medical treatment. Compared with the above three, the applications on the market need to be slightly smaller.