The basic types of refrigerated containers include thermal insulation containers, external refrigerated containers, built-in refrigerated containers, liquid nitrogen and dry ice refrigerated containers, and freezer plate refrigerated containers. A durable reefer sea container refers to a special container with good heat insulation and a certain low temperature requirement, which is suitable for the transportation and storage of various perishable foods.
With the development and improvement of the refrigeration and control technology of refrigerated containers, the range of goods suitable for refrigerated containers has been continuously expanded, including super-frozen fish with a temperature of -60 °C to flower bulbs with a temperature of 30 °C. For the goods, the humidity and air structure are used to control or adjust the fresh-keeping fruits and vegetables, etc., to ensure that the goods are delivered to the owner with the best quality, prolong the fresh-keeping period of the market, and improve the economic benefits.
- After loading the durable reefer sea container, the original quality of the refrigerated or frozen cargo should be checked and explained on the delivery list.
- During the packing process, the principle of loading and stacking should be strictly followed to avoid the unbalanced cooling caused by the short circuit of the cold air and reduce the cooling efficiency of the refrigeration unit.
- When the frozen goods are transported over long distances, the difference between the set temperature in the box and the set temperature cannot exceed 3°C. If cooling goods are transported, the temperature error should be no more than 0.5°C, preferably no more than 0.25°C.
- When transporting fresh fruits, vegetables, etc. in containers, fresh air vents should be opened in time for ventilation. However, when transporting frozen goods, the fresh air outlet should be closed.
- When transporting cooled goods packed in carton boxes, ventilation should be carried out in time according to the outdoor temperature and humidity to keep the air in the box dry and prevent condensation on the outer surface of the box.
Precautions for loading durable reefer sea container
- During the loading process of the refrigerated container, check the refrigerating device and confirm that the refrigerating machine has stopped running.
- Pre-cooling of goods: Before loading, the dunnage and other cushioning materials used in the refrigerated container should be pre-cooled, and the goods should be pre-cooled to the temperature required for transportation. Boxes are designed with limited cooling capacity and can only be used to maintain the temperature of the cargo. If the temperature of the cargo is too high, the refrigeration system will be overloaded, causing the system to fail and affecting the safety of the cargo.
- Regarding the pre-cooling of the durable reefer sea container: in general, the reefer container should not be pre-cooled, because as soon as the door of the pre-cooled reefer container is opened, water vapor will condense when the outside hot air enters the reefer container, and the water droplets will damage the outer packaging of the goods and labels, water droplets condensing on the evaporator surface affect the cooling capacity. However, when the temperature of the cold storage is consistent with the temperature in the refrigerated container, and the “cold air passage” is used for loading, the container can be pre-cooled.
- Pre-Inspection Test (PTI): Before each Cold Storage Container is delivered for use, a comprehensive inspection of the box and refrigeration system should be carried out to ensure that the reefer container is clean, undamaged and the refrigeration system is in the best condition. The cold box that has passed the inspection shall be affixed with an inspection qualified label.
- Preparations before packing: According to different perishable goods, the following items should be confirmed: optimal temperature setting; fresh air ventilation volume setting; relative humidity setting; total transportation time; cargo volume; packaging materials used and packaging dimensions; required documents and documents, etc.
- Attention should be paid before packing and when loading: the set temperature should be correct; the set fresh air ventilation volume should be correct; the set relative humidity should be correct; the refrigeration system should stop working when packing; The stacked goods should be lower than the red loading line and the vertical plane not exceeding the T-slot; the goods stacked in the box should be firm and secure; the total weight of the stacked goods in the box should not exceed the maximum allowable load of the cold box; refrigerated The total weight of the container after loading (including the weight of ancillary equipment) shall not exceed the weight limit of any transit country during transportation.
- Time out of refrigeration: short-distance transportation or refrigeration system failure may occur in the handover between various transportation methods, resulting in the stop of refrigeration. It is permissible to stop the refrigeration state for a short time for frozen and refrigerated fresh goods. A few hours off refrigeration is acceptable for many products, but not for all shipments. Prolonged cessation of refrigeration is not permitted for any refrigerated cargo. For special goods and temperature-sensitive goods, the refrigeration system should be kept working continuously to avoid any temperature fluctuations that would cause the quality of the goods to deteriorate.
Packaging of refrigerated container cargo
The durable reefer sea container packaging is an important part of the transport of refrigerated cargo and is the basis for preventing damage and contamination of the cargo. Proper design and high quality packaging materials should withstand freezing and shipping. Packaging should be able to:
- Prevent the backlog of goods from being damaged.
- Withstand the impact during transportation.
- The standard external dimensions are suitable for pallets or directly into cold boxes.
- Prevent dehydration of goods or reduce the speed of water vapor loss.
- Oxygen barrier to prevent oxidation.
- Maintain strength under low temperature and humidity.
- Prevent odor.
- Withstand the temperature of -30℃ or lower.
- It can support cargo with a stacking height of 2.3 meters (7 feet 10 inches).
Due to the above reasons, different cargoes in the durable reefer sea container should have different designs and packaging materials that meet the quality requirements. Perishable fruits and vegetables should be packaged in a package that allows air to circulate through the cargo and remove gases, moisture and heat from respiration of the cargo.