1. The importance of refrigerated containers in military logistics equipment
The logistics support of the army cannot be separated from the support of advanced military logistics and sea, land, and air transportation equipment. Modern warfare requires military logistics equipment to be versatile in order to maximize the scope of application and use existing facilities and equipment to meet the requirements of self-arming. From this perspective, containers are essential logistics equipment for troops. Among them, refrigerated containers play a very important role in military logistics equipment. They can not only be used as storage equipment for frozen and refrigerated items but also can be expanded into temporary Offices, battlefield hospitals, conference rooms, drug storage rooms, etc.
2. Application of refrigerated containers in military logistics equipment
The dimensions of military containers (including refrigerated containers, military dry containers) are generally 20.0 feet, which is the same as the dimensions of ISO standard containers; the air cargo unit load containers are generally 8 feet, and some are lower in height to facilitate loading into the cabin and hoisting of the aircraft. It can be seen that the dimensions of military containers can fully meet the needs of integrated sea, land, and air transportation.
Under the premise of meeting the requirements of military material transportation, military containers should be connected with civilian containers to the greatest extent, and conform to ISO standards in terms of external dimensions, so as to meet the requirements of military and civilian material transportation to the greatest extent and ensure that they are worldwide versatility.
2.2 Thermal insulation performance
Civil refrigerated containers must pass the heat leakage test in accordance with the requirements of the ISO standard. The interval of measurement data is 17 times; while the military reefer containers must pass the requirements of the “International Transport of Perishable Food and Special Transport Equipment Treaty”. In the heat leakage test, the interval between measurement data is more stringent for thermal insulation performance. In addition, military refrigerated containers have special requirements for the thickness of the box and the insulation materials.
For example, in order to meet the cargo’s requirements for the internal space and thermal insulation performance of refrigerated containers, vacuum insulation panels (VIP) with high thermal insulation performance are especially used. However, due to the limitation of VIP raw materials and manufacturing technology, its cost is relatively high. There is a certain degree of difficulty in popularizing and applying; however, from the current requirements for the development of a low-carbon economy, the prospects for VIP development are good.
2.3 Container type
2.3.1 Reefer containers with strapping grooves on the bottom and side panels
The reefer container with strapping grooves on the bottom and side panels can better fix the pallets in the box and is mainly used for food transportation.
2.3.2 Reefer container with shelf and door curtain in the box
The reefer container with shelves and door curtains in the box is mainly used for transporting special items (such as medicines, plasma, etc.).
2.3.3 Foldable reefer container
The foldable refrigerated container becomes a 20-foot standard container after being folded and becomes about three containers the size of a 20-foot standard container after unfolding. This type of container is generally used in battlefield hospitals, command centers, conference rooms, etc., and its function is only reflected in the unfolding of the panels, and they do not have the loading function after the panels are folded.
2.3.4 Extension Container
Extension containers are used in land, sea, and air transportation. The characteristics are to add foam layer parts at both ends of a 10-foot or 20-foot dry cargo container. The insulation layer is made of light materials, thinner and lighter; After being folded, it will become a 10-foot or 20-foot container, and the two ends will be expanded to become a 20-foot container; the interior is connected by a buckle, which is convenient to quickly change the size of the internal space, and the operation is simple without other auxiliary tools; it is widely used, commonly used in the laundry room, Toilet, etc.
The advantage of the expanded end box is that it can quickly expand the internal space. Although its internal space is occupied by the extended part, its loading capacity is limited to a certain extent, but the availability of the internal space quickly obtained through expansion is comparable to that of ordinary non-spliced containers. Since the advantages of the extended end box far outweigh the disadvantages, it is gradually being widely accepted by the army.
2.3.5 Combined reefer container
The combined reefer container is a 20-foot standard container composed of 3 or 4 small non-standard containers (see Figure 8). The appearance of the “three-in-one” combined reefer container is shown in Figure 9. The single box of the combined reefer container can store different items for easy access; there is a row of detachable stainless steel strapping plates on each side of the container, and there is also detachable stainless steel strapping rings on the baffle plate to fix the container.
Contents: forklift slots are provided on all four sides of the bottom of the box, which can meet the needs of quick assembly and disassembly operations of the container. This design meets the food hygiene requirements of the National Sanitation Foundation of the United States. It is mainly used for food transportation. The thickness of the insulation layer exceeds that of a standard refrigerated container.
The combined refrigerated container provides great convenience for the distribution of materials for scattered small troops, can realize the distribution of the same item in different locations and the distribution of different items in the same location, and meet the humanized demand for material distribution in modern warfare. In addition to storing medicines, blood products, and food, this container type can also be used to store the remains of soldiers with a working rack inside.
2.3.6 Reefer containers with special devices at the bottom or front
Developed countries have specially formulated standards for the special structure of the bottom of the container, so that, without cranes and forklifts, special transport vehicles can directly load the container without the use of additional auxiliary equipment.
Cooperative combat troops can be equipped with a common dedicated transport vehicle, as well as a refrigerated container with a special device at the bottom or front end so that the vehicle can be quickly connected to the refrigerated container, which is beneficial to the distribution and allocation of goods and equipment, and greatly meets the needs of the battlefield.
The disadvantage of this design is that a part of the space at the bottom of the refrigerated container is occupied, resulting in a reduction in the height of the container. In order to maximize the utilization of the space in the box, in addition to the outer rails at the bottom of the box, high-strength steel is used to meet the needs of improving the carrying capacity of the container.