Dong Fang International Containers
Dong Fang International Containers

Introduction to Basic Knowledge of Cooler Shipping Containers

A reefer container designed specifically for transporting cold or low temperature goods that require temperature control. It can be divided into built-in mechanical cooler shipping containers with refrigeration units and external mechanical cooler shipping containers without refrigeration units. It is suitable for loading meat, fruits and other goods. Reefer containers are expensive, with high operating costs, and attention should be paid to the technical status of the refrigeration equipment and the temperature required by the goods in the container during use.

Basic properties of cooler shipping containers

  • The reefer container adopts a galvanized steel structure, and the interior walls, floor, roof and doors of the container are made of metal composite panel, aluminum plate, stainless steel plate or polyester.

  • Container sizes and performance have been standardized internationally.

  • The applicable temperature range is -30℃~12℃, and the more common range is -30℃~20℃.

  • Reefer containers have flexible loading and unloading, stable transport temperature, low pollution and loss of goods, and are suitable for various transportation equipment. They have fast loading and unloading speed, short transportation time and low transportation costs.

  • According to the transportation mode, cooler shipping containers can be divided into sea and land transportation.

Characteristics of cooler shipping containers

  • Reefer containers can be used for intermodal transportation of various modes of transport.

  • It can achieve "door-to-door" direct transportation from the place of origin to the point of sale.

  • Under certain conditions, it can be used as a mobile refrigeration unit.

  • It can be lifted as a whole during use, with high loading and unloading efficiency, and relatively low transportation costs.

  • It has high loading volume utilization, flexible operation scheduling, and strong economic usability.

  • The new type of reefer container structure and technical performance are more reasonable and advanced, with wide applicability.

Requirements for the use of cooler shipping containers

  • After the reefer container is loaded with goods, the original quality of the refrigerated or frozen goods should be checked and explained on the bill of lading.

  • During the loading process, the principle of stacking should be strictly followed to avoid short-circuiting of cold air, causing uneven cooling and reducing the refrigeration efficiency.

  • When transporting frozen goods over long distances, the temperature difference between the set temperature and the actual temperature in the container should not exceed 3℃. If transporting cooled goods, the temperature error should not be greater than 0.5℃, preferably not more than 0.25℃.

  • When transporting fresh fruits, vegetables and other goods in cartons, the fresh air vent should be opened in a timely manner for ventilation; however, when transporting frozen goods, the fresh air vent should be closed.

  • When transporting cooled cargo in cardboard packaging, ventilation should be carried out in a timely manner according to the outdoor temperature and humidity conditions, to keep the air inside the container dry and prevent condensation on the outside surface of the packaging box.

Cooling and thermal insulation of cooler shipping containers

Reefer storage containers are usually used for transporting frozen goods with a temperature not higher than -18℃. The average cooling rate for a foot freezer container is 31.3℃/h (empty container); however, after loading, the cooling rate will be greatly slowed due to the large heat capacity of the goods, and it may take 15-16 hours to reach the set temperature. If the incoming temperature is high, it may take 2-3 days to reach the set temperature. The temperature rise and fall speed inside the reefer container is related to the goods loaded inside the container. After reaching the set temperature range of -18℃±3℃, the temperature inside the container should be kept stable.