Cold storage temperature can not drop and reduce the slow is more common phenomenon. Now on the library temperature to reduce the causes of slow analysis, hope to be able to bring a small amount of assistance to everyone’s work.
1, cold storage because of poor insulation or sealing function, resulting in cold loss. Heat insulation function is poor because of the pipeline, warehouse insulation wall thickness of the insulation layer is not, heat insulation and thermal insulation effect is poor, it is the design of the insulation layer thickness selection is not proper or construction of the insulation material quality caused by poor. In addition, in the process of construction and use, the insulation material insulation and moisture-proof function can be damaged resulting in the insulation layer moisture, deformation, and even ulceration, and its thermal insulation and heat preservation can be reduced, the library of cold loss with the change, the library temperature is reduced significantly slowed down. Another important cause of cold loss is the warehouse sealing function is poor, there are more hot air from the leakage of air into the warehouse. Usually if the sealing strip in the warehouse door or cold storage wall sealing presents a broken dew phenomenon, it is clarified that the seal is not tight. In addition, frequent opening and closing of the warehouse door or more people into the warehouse, will also increase the warehouse cold loss. Should try to avoid opening the door to avoid a lot of hot air into the warehouse. Of course, the warehouse into the inventory frequently or into the goods is too large, the heat load dramatically larger, to cool down to the rule temperature usually takes a long time.
2, the exterior of the evaporator frost is too thick or too much dust, the role of heat transfer is reduced, resulting in the slow reduction of library temperature is another important cause of another important reason for the evaporator heat transfer power is low, this is mainly because of the exterior of the evaporator frost layer is too thick or dust is too much to cause. Because most of the cold storage evaporator exterior temperature below 0 ℃, and warehouse humidity is relatively high, the moisture in the air is easy in the evaporator exterior frost, and even ice, affecting the role of heat transfer evaporator. In order to avoid the appearance of the transpirator frost layer is too thick, need to defrost it regularly.
3, the presence of more air or refrigeration oil in the transporter, heat transfer role is reduced, once the transporter heat transfer tube attached to the inner surface of the more refrigeration oil, the heat transfer coefficient will be reduced, the same, if there is more air in the heat transfer tube, the heat transfer area of the transporter is reduced, the power of its heat transfer will be significantly reduced, the warehouse temperature reduction rate is slowed down. Therefore, in the usual work protection, should pay attention to the timely eradication of the steamer heat transfer tube inside the appearance of oil and discharge the air in the steamer, in order to improve the heat transfer power of the steamer.
4, the throttle valve is not properly adjusted or blocked, refrigerant flow is too large or too small. Throttle valve improperly regulated or blocked, will directly affect the refrigerant flow into the transporter. When the throttle valve is open too large, the refrigerant flow is large, transpiration pressure and transpiration temperature also rise, the warehouse temperature reduction rate will slow down; when the throttle valve is open too small or blocked, the refrigerant flow is also reduced, the system's refrigeration capacity is also reduced, the warehouse temperature reduction rate will slow down the same. Usually through the investigation of transpiration pressure, transpiration temperature and suction pipe frost condition to determine the throttle refrigerant flow is not appropriate. Throttle blockage is an important factor affecting the refrigerant flow, resulting in throttle blockage is the primary cause of ice blockage and dirty blockage. Ice blockage is due to the drying effect of the dryer is not good, the refrigerant contains water, flow through the throttle valve, the temperature drops to below 0 ℃, the moisture in the refrigerant into ice and block the throttle hole; dirty blockage is because of the throttle valve inlet filter mesh on the accumulation of a large number of dirt, refrigerant flow is not smooth, constituting a blockage.
5, the amount of refrigerant in the system is lacking, the lack of refrigeration capacity. Lack of refrigerant cycle volume is mainly due to two reasons, one is the lack of refrigerant charge, at the moment, just make up for the full amount of refrigerant can be. Another reason is that the system refrigerant leakage is more, meet this situation, should first look for leaks, the main point of view of the pipeline, the valve joints, to find out the leakage of parts of the repair, and then charge the full amount of refrigerant.
6, the compressor power is low, the refrigeration capacity can not satisfy the warehouse load demand compressor because of long time work, cylinder liner and piston rings and other parts because of wear and tear severe, cooperation gap becomes larger, the sealing function will be reduced accordingly, the compressor's transmission coefficient is also reduced, the refrigeration capacity will be reduced. When the cooling capacity is less than the warehouse heat load, will lead to warehouse temperature reduction slow. Compressor can be investigated through the compressor suction and discharge pressure to determine the refrigeration capacity of the compressor. If the compressor refrigeration capacity is reduced, the common method is to replace the compressor cylinder liner and piston ring, if the replacement is still not effective, it should think about other factors, and even dismantle the machine maintenance, troubleshooting factors.
Post time: Jul-12-2023
