Cold storage is the basis for the development of the cold chain industry, is an important part of the cold chain, and is also the largest market segment in the cold chain industry. With the demand of cold chain logistics enterprises for storage, the construction scale of cold storage has grown from small to large, from small to large, and has made rapid progress all over the country. The installation of cold storage in coastal areas and fruit and vegetable producing areas has made more rapid progress, and it has occupied a very important position in the national economy. However, until now, there have been some serious problems before, during and after the use of cold storage, As a result, the number of years of operation of the cold storage is reduced and the phenomenon of serious energy consumption and material consumption greatly increases the operating cost of the cold storage and weakens the overall service life of the cold storage. These problems in the use of the cold storage are often closely related to daily maintenance and repair.
The cold storage is generally composed of maintenance structure and refrigeration equipment. It is mostly cooled by compressor, using liquid with very low gasification temperature as coolant to make it evaporate under low pressure and mechanical control to absorb heat in the storage, so as to achieve the purpose of cooling. The most commonly used refrigeration system is mainly composed of compressor, condenser and evaporator. In the daily use process, the maintenance of the cold storage, especially the compressor, condenser, refrigeration unit and power supply, should be carried out from time to time. According to the cold storage project undertaken, HGS HEGERLS storage service manufacturer has certain knowledge and practical experience in cold storage production, cold storage construction, cold storage installation, cold storage sales and maintenance, etc. In this regard, HGS HEGERLS has further sorted out the cold storage maintenance and repair for the problems that have occurred in the use of cold storage.
Comprehensive safety inspection: After the cold storage and refrigeration equipment used in the cold storage are newly installed or stopped for a long time, comprehensive inspection and commissioning shall be carried out before the next use. Under the condition that all indicators are normal, the refrigeration equipment can be started up under the guidance of professional refrigeration technicians.
Environmental protection of cold storage: For small fabricated cold storage, during the construction process, the ground needs to use insulation boards, and when using the cold storage, a large amount of ice and water should also be prevented from being stored on the ground. If there is ice, hard objects should not be used to knock when cleaning to prevent damage to the ground. In addition, during the use process, attention should be paid to the collision and scratch of hard objects on the cold storage body and the outer body, because hard objects can cause depression and corrosion, In serious cases, the local thermal insulation performance will be reduced.
Maintenance of the sealing part of the cold storage: since the fabricated cold storage is spliced by several insulation boards, there are certain gaps between the boards. During construction, these gaps need to be sealed with sealant to prevent air and water from entering. In this regard, some parts with sealing failure shall be repaired in time during use to prevent cold escape.
Cold storage system: In the initial stage, the internal cleanliness of the system was poor, and the refrigerant oil should be replaced after 30 days of operation. For the system with high cleanliness, it should be completely replaced after half a year of operation (depending on the actual situation). Also check the exhaust temperature. During seasonal operation, pay special attention to the operating state of the system, and timely adjust the system liquid supply and condensation temperature.
Evaporator: For the evaporator, check the defrosting condition frequently. (Note: whether the defrosting is timely and effective will affect the refrigeration effect, resulting in liquid return of the refrigeration system.)
Air cooler: the condenser of the air cooler shall be checked frequently, and the scale shall be removed in time in case of scaling; Clean the air cooler frequently to keep it in good heat exchange state. Check whether the motor and fan can rotate flexibly, and add lubricating oil in case of blockage; If there is abnormal friction sound, replace the bearing with the same model and specification, clean the fan blade and coil, and timely clean the dirt on the water pan.
Compressor detection: the oil level of the compressor, the oil return condition and the cleanliness of the oil shall be frequently observed during the initial operation of the unit. If the oil is dirty or the oil level drops, the problem shall be solved in time to avoid poor lubrication; At the same time, always observe the operating state of the compressor, carefully listen to the operating sound of the compressor and condenser fan, or timely deal with any abnormality found, and check the vibration of the compressor, exhaust pipe and foundation; Also check whether the compressor has abnormal smell. The refrigeration technician needs to inspect and maintain the compressor once a year, including checking the oil level and oil color of the compressor. If the oil level is lower than 1/2 of the position of the observation glass, the reason for oil leakage needs to be found out, and the fault can be eliminated before filling lubricating oil; If the oil has changed color, the lubricating oil needs to be completely replaced.
Refrigeration system: it is necessary to check whether there is air in the refrigeration system. If there is air, it is necessary to discharge air to ensure the normal operation of the refrigeration system.
Voltage detection: frequently check and confirm whether the voltage of the power supply meets the requirements. The general voltage should be 380V ± 10% (three-phase four wire), and check whether the protection function of the power supply main switch is normal and effective. (What HEGERLS needs to remind us is that when the cold storage equipment is not used for a long time, it is necessary to cut off the main power supply of the fresh-keeping cold storage to ensure that the cold storage equipment is not affected by moisture, electricity leakage, dust and other substances.)
Pipe of refrigeration unit: regularly check whether each connecting pipe of the refrigeration unit and the connecting pipe on the valve are firm and whether there is refrigerant leakage (oil stain will appear in the general leakage place). Practical method for leak detection: sponge or soft cloth is dipped with detergent, rubbed and foamed, and then evenly coated on the place to be leak detected. Observe for several minutes: if there will be bubbles in the leakage, mark the leakage place, and then do fastening or gas welding treatment (this inspection needs to be carried out by professional cooling personnel).
Control line operation: all control lines need to be bundled and laid along the refrigerant pipe with shielded wires; And all refrigerant pipe insulation pipes must be bound with binding tape, and when passing through the floor, steel casing shall be used; The indoor controller needs to be embedded in the pipe, and it is also forbidden to bundle the power cord and control cord together to prevent interference.
Lifting points: The lifting points can be customized according to the number of top fixing points of the cold storage. Each hanger cross arm needs to be installed with a pair of chain blocks, which plays the role of aligning and adjusting when fixing; All lifting points need to be lifted at the same time to maintain a consistent height and play a stable role; When the hoisting is in place and leveled, it needs to be welded with the fixed lifting point on the top of the warehouse. In this way, more long chain blocks need to be prepared. When lifting operation is carried out, there must be a professional staff to command the operation. At the same time, when chain block is carried out, the staff must not stand directly below the pipe.
Shutdown fault: when the machine is not started for a long time or stopped after a long time of startup or when the warehouse temperature is not enough, it is necessary to check whether there is dirt on the condenser. Poor heat dissipation will lead to high condensation pressure of the refrigerator. To protect the compressor, the machine stops under the action of the pressure controller. When the heat dissipation is good, press the black reset button on the pressure controller, and the machine can automatically resume operation; If the parameter setting of the controller is incorrect, reset it; Temperature control failure; Electrical appliances are damaged; These are the causes of downtime, and we must pay attention to them during daily use.
The throttle valve of the cold storage is improperly adjusted or blocked, and the refrigerant flow is too large or too small: The throttle valve is improperly adjusted or blocked, which will directly affect the refrigerant flow into the evaporator. When the throttle valve is opened too much, the refrigerant flow is too large, and the evaporation pressure and temperature are also increased; At the same time, when the throttle valve is too small or blocked, the refrigerant flow will also decrease, and the refrigeration capacity of the system will also decrease. Generally, the proper refrigerant flow of throttle valve can be judged by observing the evaporation pressure, evaporation temperature and frosting of suction pipe. Choke valve blockage is an important factor affecting refrigerant flow, and the main causes of throttle valve blockage are ice blockage and dirty blockage. Ice blockage is due to the poor drying effect of the dryer. The refrigerant contains water. When flowing through the throttle valve, the temperature drops below 0 ℃, and the water in the refrigerant freezes and blocks the throttle valve hole; Dirty blockage is due to the accumulation of more dirt on the filter screen at the inlet of the throttle valve, and the poor circulation of the refrigerant, resulting in blockage.
Extending the service life of the cold storage can not only save costs and improve efficiency for enterprises, but also make full use of resources, which is the embodiment of its full value. It is hoped that the cold storage manufacturers, cold storage installation companies, cold storage design companies, and enterprise users who purchase cold storage equipment can pay high attention here. For more questions, please consult the manufacturer of HEGERLS cold storage, and HEGERLS will provide you with reasonable solutions according to your site conditions.
Post time: Oct-12-2022