About Container Dimensions and Capacity
CONTAINER | Capacity | Recommended Load Volume |
|||||
Nominal Dimension |
Length | Width | Height | Cubic Feet |
Cubic Meter |
Cubic Feet |
Cubic Meter |
External | 20′ | 8′ | 8′ 6″ | ||||
6.096 m | 2.438 m | 2.591 m | |||||
Internal | 19′ 4.25″ | 7′ 8.625″ | 7′ 10″ | 1170 cft | 1000 cft | ||
5.899 m | 2.353 m | 2.388 m | 33.131 cbm | 28 cbm | |||
External | 40′ | 8′ | 8′ 6″ | ||||
12.192 m | 2.438 m | 2.591 m | |||||
Internal | 39′ 5.375″ | 7′ 8.625″ | 7′ 10″ | 2385 cft | 2050 cft | ||
12.024 m | 2.353 m | 2.388 m | 67.535 cbm | 58 cbm | |||
External | 40′ Hicube | 8′ | 9′ 6″ | ||||
12.192 m | 2.438 m | 2.896 m | |||||
Internal | 39′ 5.375″ | 7′ 8.625″ | 8′ 10″ | 2690 cft | 2350 cft | ||
12.024 m | 2.353 m | 2.692 m | 76.172 cbm | 66 cbm |
NOTE: | Containers with the same external length may not have exactly the same internal length and width. |
The Recommended Load Volume (RLV) refers to the suggested maximum cube to use in calculating a full container load. The RLV can be about 10-15% less than the container capacity, depending on the export pack dimensions. |
Rear view of 20′ x 8.5′ container | CAUTION:
Miscalculated capacity may result in a large empty and unusable space or a shortage in space. For example (see 20′ x 8.5′ container diagram on the left), the master cartons have a uniform height of 20 inches, and the length and width are greater than the height. If 1170 cubic feet is used to calculate a 20′ full container load, most likely some cartons will not fit despite the empty space of about 170 cubic feet. You cannot stuff the remaining cartons into the remaining 14″ high empty space.
|
Tare Mass
Tare weight or tare is the mass (or weight) of empty container, including all fittings and appliances used in a particular type of container in its normal operating condition.
Rating
Payload is the maximum permitted mass (or weight) of payload, including the dunnage and cargo securement arrangements that are not associated with the container in its normal operating condition. Therefore, Payload = Rating – Tare Mass.
If the tare mass of a 20′ dry cargo container is 2,400 kgs. and a 40′ is 3,900 kgs., the payload of 20′ is 21,600 kgs. (i.e., 24,000 kgs. minus 2,400 kgs.) and 40′ is 26,580 kgs. (i.e., 30,480 kgs. minus 3,900 kgs.). However, the exporter may be prohibited to have that much payload in areas where there are legal limitations to the overall load of a vehicle.
In exporting, it is common to encounter a payload of 17,500 kgs. or less in the 20′ container, and 24,000 kgs. or less in the 40′ container.
The rating, tare mass and payload of a container is marked on its wall, usually on the end (rear) door in the case of an end-loading dry cargo container.
Figures
Usage
20″ Tank
INSIDE LENGTH | 6.058 m | |
INSIDE WIDTH | 2.438 m | |
INSIDE HEIGHT | 2.4380 m |
Tank containers must be at least 80% full, to prevent dangerous surging of the liquids in transit. On the other hand, they must not as a rule be over 95% full, or there will not be sufficient ullage space for thermal expansion. The extent of thermal expansion may be calculated for each cargo on the basis of the following formula:
- ΔV = Va · γ · ΔT
- Ve = Va (1 + γ · ΔT)
ΔV : change in volume
Va : volume at initial temperature a
Ve : final volume at temperature e
γ : coefficient of cubic (thermal) expansion
ΔT : temperature difference in degrees kelvin
Tank containers intended for transporting foodstuffs must be labeled “Potable Liquids only”.
If the cargo requires temperature-controlled transport, tank containers can be equipped with insulation or heating. The temperature of the cargo may be precisely controlled using temperature sensors.
Figures
Usage
Tank containers are used for liquid cargoes, such as:
- Foodstuffs: fruit juices, spirits, sweet oils
- Chemicals: hazardous materials, such as fuels, toxic substances, corrosion protection agents
20″ Standard
INSIDE LENGTH | 5.8950 m | |
INSIDE WIDTH | 2.350 m | |
INSIDE HEIGHT | 2.392 m |
- Standard containers with doors at one or both end(s)
- Standard containers with doors at one or both end(s) and doors over the entire length of one or both sides
- Standard containers with doors at one or both end(s) and doors on one or both sides
Figures
Usage
Standard containers are used for all types general cargo (dry cargo).
20″ Open Top
INSIDE LENGTH | 5.8880 m | |
INSIDE WIDTH | 2.345 m | |
INSIDE HEIGHT | 2.315 m |
The walls of open-top containers are generally made of corrugated steel. The floor is made of wood.
It has the following typical distinguishing structural features. The roof consists of removable bows and a removable tarpaulin. The door header may be swivelled out.
These two structural features greatly simplify the process of packing and unpacking the container. In particular, it is very easy to pack and unpack the container from above or through the doors by crane or crab when the roof is open and the door header is swivelled out.
It should be noted, however, that the purpose of the roof bows of an open-top container is not solely to support the tarpaulin but also to contribute to container stability. Flatracks are therefore more suitable for overheight cargoes.
Lashing rings, to which the cargo may be secured, are installed in the upper and lower side rails and the corner posts. The lashing rings may take loads of up to 1,000 kg.
Usual open-top container dimensions are 20′ and 40′.
Figures
Usage
Open-top containers are used for all types of general cargo (dry cargo). Their principal uses are as follows:
- packing and unpacking from above or through the doors by crane or crab
- tall cargo
20″ FLATRACK
INSIDE LENGTH | 5.698 m | |
INSIDE WIDTH | 2.230 m | |
INSIDE HEIGHT | 2.2550 m |
Flatracks consist of a floor structure with a high loading capacity composed of a steel frame and a softwood floor and two end walls, which may either be fixed or collapsible. The end walls are stable enough to allow cargo securing means to be attached and several flatracks to be stacked on top of one another. Flatracks are available in 20′ and 40′ sizes.
A number of lashing rings, to which the cargo may be secured, are installed in the side rails, the corner posts and the floor. The lashing rings may take loads of up to 2000 kg in the case of 20′ flatracks or up to 4000 kg in the case of 40′ flatracks. Some types of 20′ flatracks have forklift pockets. 40′ flatracks have gooseneck tunnels at each end. In addition, they are sometimes equipped with lashing winches with 2 metric ton lashing belts. For transport of certain cargoes, flatracks may be provided with stanchions.
Figures
Usage
Flatracks are mainly used to transport heavy-lifts and overheight or overwidth cargoes.
20″ FLATRACK COLLAPSIBLE
INSIDE LENGTH | 5.675 m | |
INSIDE WIDTH | 2.2130 m | |
INSIDE HEIGHT | 2.270 m |
Flatracks consist of a floor structure with a high loading capacity composed of a steel frame and a softwood floor and two end walls, which may either be fixed or collapsible. The end walls are stable enough to allow cargo securing means to be attached and several flatracks to be stacked on top of one another. Flatracks are available in 20′ and 40′ sizes.
A number of lashing rings, to which the cargo may be secured, are installed in the side rails, the corner posts and the floor. The lashing rings may take loads of up to 2000 kg in the case of 20′ flatracks or up to 4000 kg in the case of 40′ flatracks. Some types of 20′ flatracks have forklift pockets. 40′ flatracks have gooseneck tunnels at each end. In addition, they are sometimes equipped with lashing winches with 2 metric ton lashing belts. For transport of certain cargoes, flatracks may be provided with stanchions.
Figures
Usage
Flatracks are mainly used to transport heavy-lifts and overheight or overwidth cargoes.
20″ PLATFORM
INSIDE LENGTH | 6.0580 m | |
INSIDE WIDTH | 2.438 m | |
INSIDE HEIGHT | 0.370 m |
Platforms consist solely of a floor structure with extremely high loading capacity; they have no side or end walls. This high loading capacity makes it possible to concentrate heavy weights on small areas. A platform consists of a steel frame and a wooden floor structure.
Platforms are available in 20′ and 40′ sizes. 40′ platforms have a gooseneck tunnel at each end. Lashing rings, to which the cargo may be secured, are installed in the side rails. The lashing rings may take loads of up to 3.000 kg.
Figures
Usage
Platforms are used principally for oversized and very heavy cargoes.
20″ Refrigerated
INSIDE LENGTH | 5.724 m | |
INSIDE WIDTH | 2.286 m | |
INSIDE HEIGHT | 2.0140 m |
The refrigeration unit is arranged in such a way that the external dimensions of the container meet ISO standards and thus fit into the container ship cell guides, for example. The presence of an integral refrigeration unit entails a loss of internal volume and payload.
When being transported by ship, integral units have to be connected to the on-board power supply system. The number of refrigerated containers which may be connected depends on the capacity of the ship’s power supply system. If the aforesaid capacity is too low for the refrigerated containers to be transported, “power packs” may be used, which are equipped with relatively large diesel generators and satisfy ISO requirements with regard to the dimensions of a 20′ container. When at the terminal, the containers are connected to the terminal’s power supply system. For transport by road and rail, most integral unit refrigeration units are operated by a generator set (genset). This may either be a component of the refrigeration unit or connected to the refrigeration unit.
In the upper area of the container, adequate space (at least 12 cm) must likewise be provided for air flow. For this purpose, during packing of the container adequate free space must be left above the cargo. The maximum load height is marked on the side walls.
To ensure vertical air flow from bottom to top, packaging must also be appropriately designed and the cargo must be sensibly stowed. In addition to temperature regulation, integral units also allow a controlled fresh air exchange, for example for the removal of metabolic products such as CO2 and ethylene in the case of the transport of fruits.
In the refrigeration units, both the supply and return air temperatures are measured and, depending on the operating mode, one of these values is used to control the cold air. Temperature measurement may be performed in various ways. The Partlow recorder generally records return air temperature, since this provides an indication of the state or temperature of the cargo. Data loggers are increasingly used, which detect temperature digitally and indicate it on a display. Once transferred to a PC, the data may then be evaluated. The temperature display is attached to the outside of the refrigeration unit, so that operation of the unit may be checked at any time. Digital or analog recorders may also be positioned directly in the cargo, so as to measure temperatures inside the container. The recorder should be accommodated in such a way that it records the temperatures at risk points in the container (inside the packaging, top layer at door end).
Figures
Usage
Refrigerated containers are used for goods which need to be transported at a constant temperature above or below freezing point. These goods are divided into chilled goods and frozen goods, depending on the specified transport temperature. They principally include fruit, vegetables, meat and dairy products, such as butter and cheese. High-cube integral units are used in particular for voluminous and light goods (e.g. fruit, flowers).
Nowadays, goods requiring refrigeration are mostly transported in integral units, which have a markedly higher market share than porthole containers. Chilled meat is sometimes also transported hanging, for which purpose the ceilings of refrigerated containers are equipped with special hook rails.
40″ Standard
INSIDE LENGTH | 12.029 m | |
INSIDE WIDTH | 2.350 m | |
INSIDE HEIGHT | 2.392 m |
- Standard containers with doors at one or both end(s)
- Standard containers with doors at one or both end(s) and doors over the entire length of one or both sides
- Standard containers with doors at one or both end(s) and doors on one or both sides
In addition, the various types of standard container also differ in dimensions and weight, resulting in a wide range of standard containers. Standard containers are mainly used as 20′ and 40′ containers. Containers with smaller dimensions are very seldom used. Indeed, the trend is towards even longer dimensions, e.g. 45′.
Figures
Usage
Standard containers are used for all types general cargo (dry cargo).
40″ High-Cube
INSIDE LENGTH | 12.024 m | |
INSIDE WIDTH | 2.350 m | |
INSIDE HEIGHT | 2.697 m |
High-cube containers are similar in structure to standard containers, but taller. In contrast to standard containers, which have a maximum height of 2591 mm (8’6″), high-cube containers are 2896 mm, or 9’6″, tall. High-cube containers are for the most part 40′ long, but are sometimes made as 45′ containers.
A number of lashing rings, capable of bearing loads of at most 1000 kg, are mounted on the front top end rail and bottom cross member and the corner posts. Many 40′ containers have a recess in the floor at the front end which serves to center the containers on so-called gooseneck chassis. These recesses allow the containers to lie lower and therefore to be of taller construction.
Figures
Usage
High-cube containers are used for all types general cargo (dry cargo). However, they are particularly suitable for transporting light, voluminous cargoes and overheight cargoes up to a maximum of 2.70 m tall.
References Site: export911