An intermodal container is another name for the shipping containers. Or containerized cargo are intermodal containers. Once the cargo is loaded into a container by a shipper it could transport in vessels, rails, and trucks without destuffing the goods until they reach the destination port.
Hence these shipping containers are often called as intermodal containers. In order to smooth the container operation and container shipping International Organisation for Standards (ISO) has standardized the container sizes. This was a huge advantage to the containerized cargo.
Same as the Unit Load Devices or the air freight containers, sea transportation also has different types of containers to meet the customer’s requirements.
More than 60% of global trade moves via container shipping. Out of that 90% carry in general-purpose containers. And we can say 80% cargo carry in the 20 and 40-foot standard-sized containers.
There are special type containers to carry other cargo like OOG and some liquid cargo.
Each container has 8 twist locks on the 8 corners of the container. Containers can lock with another container or onto a trailer or in the vessel using these twist locks.
As per the ISO 1496 of 1990 standard containers can stack one on one. We simply say containers can stack 10 higher. Yet modern ships are capable of stacking containers more than 10 higher to achieve economies of scale.
In general, containers are made with aluminum. Further general containers are airtight and water-resistant to prevent damage to cargo from the outside.
Signs and Marks on Containers
Each and every container has a unique number to identify the container. According to the ISO 6346 reporting mark, every container gets an ownership code. This ownership code or the reporting mark is issued by the Bureau International des Containers (International container bureau, abbr. B.I.C.) headquartered in France.
These reporting marks contain four letters with an ending letter of U, J or Z. After the four letters unique six digits and a check digit to be followed.
The letter represent below:
U for all freight containers,
J for detachable freight container-related equipment,
Z for trailers and chassis
The check digit is a single Arabic number and it is for the purpose of validating the recording and transmission accuracies of the ownership code and serial number.
There are few codings that are marked on a container. The series of codes on a container contains the manufacturer code, the ownership code, usage classification code, UN placard for hazardous goods, and reference codes.
What is the CSC Plate?
For the safety of the containers and container shipping United Nations and the International Maritime Organisation jointly convinced a convention in 1972. This is called the International Convention for Safe Containers (CSC).
As per the convention, any container used for international transport must be fitted with a valid safety approval plate (CSC Plate). A safety plate is riveted to the outside of the left door of the container at the time of manufacturing.
Information on the CSC plate should be either in English or French. Further the wording of “CSC SAFETY APPROVAL” should be embodied in the plate and country of approval and the approval reference should be mentioned.
It is the responsibility of container owners to do the safety checks for every container they have. Every container must be examined not more than 5 years after manufacturing, and thereafter at intervals of less than thirty months. The next inspection date of the container (NED) should be mentioned on the CSC plate.
What is the letter stands end of a container number?
The letter mentioned at the end of each 6 digits number shows the type of the container.
R1 – Refrigerated Container
U1 – Open Top Container
P1 – Platform Container
T1 – Tank Container
What are the Markings on a Container?
There are mandatory markings to be done on an intermodal container. This is to give a visual warning to the users and to convey the information about the container.
Types of Intermodal Containers
As mentioned above there are different types of intermodal containers available. Below are a few and commonly available container types and their dimensions.
These are the most commonly used container type. 20 foot and 40-foot containers are highly used for intermodal transportation. NVOCCs and freight forwarders commonly use these types of containers to consolidate cargo from their customers. Usually palletized cargo, boxed cargo in sacks, and bags stuff inside these containers.
High Cube Container
High cube containers are also known as Hi-cube containers. High cube containers are very similar to normal containers. The only difference is the height of these containers is higher than the normal containers. If you see a container with a yellow and black color zebra mark on top of a container door, that is the indicator to easily identify a high cube container.
Reefer containers are the same as the general container. But specialized to support the cold supply chain. All the temperature-sensitive cargo stuffed in reefer containers. Reefer containers can have a temperature control between -30°C and +30°C.
Since these containers need to be powered to keep the cooling system on, shipping a reefer container cost much more than a normal container. Reefer containers have the capability to cool or freeze the cargo. 20 TEU container size uses to build the reefer containers.
Open Top Containers
Open top containers have an open-top for the container. These are the best fit for the OOG cargo. If the cargo height cannot be fitted to a normal container, an open-top container would be the best solution. As the top of the container is removable you have more space than in a normal container. Also, tarpaulin sheets use to make the top cover. Users can either keep the top open or use the tarpaulin cover to cover the container top.
Hard Top Containers
Hard top containers are similar to open-top containers. The only difference is instead of a tarpaulin sheet it has a detachable steel roof. This roof can move using a forklift as the hard roof has pockets for lifting.
Pallet Wide Containers
Pallet wide containers are specially designed and commonly used in Europe. These containers designed to carry pallets. Pallet wides are available in 20, 40, and 40 high cube sizes. In normal containers, 11 units of 120 x80 x14.4 CM size pallets can be loaded while 15 of the same can be stuffed in a pallet wide container.
Flat Rack Containers
Flat rack containers come with open 2 sides. Mostly use to carry heavily weighted cargo. Flat racks have a few lashing rings along the flatbed of the container. This ensures the cargo stay fit to the flat bed while transporting.
The stacking of empty flat rack containers is not easy due to the nature of its dimension. Some flat racks have collapsable side doors while some do not. Collapsable empty flat racks can be stacked one on one to save space.
Open Side Containers
Open side containers are also known as side door containers. Other than the side door, the structure of one long side of the container work as an extra door. These containers are convenient for the cargo which cannot be loaded from the small side door.
Double Door Containers
Double door containers have openable doors on both sides of the container. These types of containers are well suited to transport wheeled vehicles as the vehicle can drive in from one door and drive out from the other door at the destination. In general wheel cargo are transported in RORO ships and high end vehicles are transported using double door containers.
These containers also known as tunnel containers.
Ventilated containers are also known as coffee containers as they are highly used to transport coffee. 20 foot containers use as ventilation containers. The only difference is these containers have two corners or four corners ventilation instead of airtight feature in general 20 foot containers. The openings of the container to provide ventilation do not attract rainwater or dust into the container.
Tank containers are a little different from the other containers. This type of container has a tank and a frame around the tank. Tank containers are used to transport hazardous liquids as well as non-hazardous liquids like edible oil.
These containers have the facility to pump the liquid in and out with the fitted safety devices.