How are Containers Stored in the Terminal and on the Ship?

How Does the Terminal Track Containers?

Each container has its own unique reference code of up to 12 numbers and letter, e.g. HLCU 3176562.

This number along with other coded information about the size and type of the container, the cargo content, if it is refrigerated, hazardous or non-standard height, width or length, the weight, port of destination and ship are declared to the terminal by the shipping line.

The information is transferred electronically from computer to computer. This is known as Electronic Data Interchange (EDI). Alternatively the shipping line can enter the information directly into the terminal computer, from anywhere in the country.

Import and export information is received by EDI using data links established with the shipping lines.

Community Network Services Limited (CNS), is a specialist company, owned by DP World Southampton, to provide the service EDI. The information is available to HM Revenue & Customs (HMRC) so that they can check that any duty and VAT due has been paid by the importer, as well as checking the container for any smuggled items. In the case of exports HMRC can check if the exporter has a licence to ship cargo to another country.

The Port Health Authority also uses this information to undertake checks on food products, before they reach the shops.

The ships bay plan, created by the shipping lines' stowage coordinator in the Far East, the Americas and Europe are processed in the DP World Southampton computer and the information is used to check that we have the right container and to track them from the ship to the stacking area and vice versa.

Before a lorry arrives to pick up or deliver a container the haulage company must make a booking through the terminal’s Vehicle Booking System (VBS), which is available over the Internet, to reserve a time slot to have an export or empty container lifted off and an import container lifted on.

When the lorry arrives it goes to a marshalling area known as the pre gate where the computer system will work out the next stages of his journey around the container terminal.

The computer knows the grid location for every slot on the terminal and areas on the terminal for specific voyages can be programmed into the computer.

An export container arriving by road, for example, will be given a slot position as near as possible to the position where the ship will dock. The containers are sorted by voyage, port and weight in the container yard. This helps to avoid unproductive moves, known as shuffles, when the ship is loaded.

The computer using Radio Data Transfer (RDT) technology sends out the information required to direct the straddle carrier driver and the location is tracked using a satellite navigation system, Differential Global Positioning System (DGPS).

How are Containers Secured on the Ship?

Containers must be secured to the ship’s structure. A container ship in a big storm can roll over to about 30 degrees or more and sometimes quite violently.

Below the deck level they are loaded between cell guides, which stop the containers from moving about.

Sometimes special fittings are used below deck where 40 ft containers are loaded on top of twenty ft containers.

Once the under deck has been loaded, large pontoon hatches weighing around 30 tonnes are lifted back on board, there are two or three pontoon hatches per bay, and secured to the ship.

Containers are loaded on these pontoons and can be piled up to six high on the deck. The first two or three tiers are secured by attaching strong bars to the end of each container. These bars are then secured to the pontoon hatch with bottle screws which tighten up the bars.

The last two or three layers are secured with special devices called twistlocks or conlocks, which lock each corner of the container to the one below.