How Does Logistics Container Work?

08 Apr.,2024

 

If you are like us, you have seen wharfs and ports and been fascinated by the huge ships, cranes, trucks and most of all by the containers stacked like building blocks.

But what are the processes for container ports? How are containers unloaded, where do they go, and what happens next?

We are going to find out if containerization is as orderly as it seems, or if there is some chaos in these neatly stacked rows – and what opportunity and challenges automation has brought to the shipping industry.

Containerization has changed the world. Previously, ships would hold multiple smaller loads all jumbled together into a cargo hold – now the sorting of cargo into containers is done before the cargo is loaded.

This allows ships to have a greater efficiency when loading and unloading cargo. But it has also brought new challenges for organization, as gigantic ships dock in large ports and need to unload hundreds or thousands of containers at a time.

Container terminals are hubs of intermodal transport. That means the containers are switching models of transport, from a ship, which travels on the sea, to either road or rail.

Containers can also be moved by air – but this is not usually the focus of container ports.

Switching modes of transport is not quite as simple as loading a cargo container from a ship onto a truck – multiple steps and organizational challenges are involved before the container rolls out of the freight yard.

First – the container must be unloaded from the ship. This is achieved with huge gantry cranes that are able to lift the several tones of container and its cargo.

Example of a Gantry Crane

Cranes can be hinged to allow for passage of large ships beneath, or can be fixed, to reduce airspace being taken up.

Cranes connect to containers by their fittings – which, like most other parts of a container are standardized throughout the world, by the International Organization for Standardization.

Another international standard is the unique identifier number which helps to keep track of each container.

The containers are typically loaded onto Terminal Tractors. These funny looking trucks are meant for short-distance haulage, in order to get the container from beside the ship, into the storage yard where the containers wait to be picked up by a truck or a train.

A Terminal Tractor

In order to move containers around a storage yard, and onto trucks and train, there are several options for machinery – two of the most interesting are reach stackers and rubber-tyre gantries.

Rubber-tyre gantries have wheels, and are cranes that are able to fully straddle containers. Larger versions may run on tracks, rather than tyres, and can be straddle multiple rows of containers.

Reach-stackers have a long arm that can easily be used to stack containers several rows deep, or to negotiate them onto semi-trailers and rail cars.

Every step of the process described so far has the capacity to be fully – or semi-automated. And in fact, at some of the terminals at the Port of Rotterdam in the Netherlands – they all are, at least partially.

At this port, a crane operator remotely operates the gantry crane via computer software that unloads containers from a ship.

The container is loaded onto a fully automated terminal truck which drives it to the storage area to be unloaded by an automated stacker crane.

This is one area where logical planning augmented by computers can provide a huge benefit. Knowing exactly what date and time a container needs to be picked up, a computer can plan the most efficient way to stack containers.

This ensures the container isn’t buried too deep in the stacks when it comes time to leave the yard, reducing the number of operations required to access the required container.

There are still some storage yards around the world that used a paper-based tracking system. For some of these yards, this means that containers are simply stacked according to when they are brought in to the storage yard – so that when the time comes to take them out again, they might be at the bottom of a stack of containers.

Like many other industries, computerized automation provides some unique benefits over human-operation, such as accuracy of repetitive tasks and logical planning of efficient processes – until something goes wrong and many hours are spent trying to troubleshoot and fix the issue.

For now at least, humans maintain the advantage of adaptability over fully-automated machines.

Automating a container port is very expensive, but ports implementing this technology hope to gain benefits such as increased productivity, and increased safety.

Of course, even at ports where automation exists, humans are still employed to oversee and maintain the machines and rectify problems as they arise.

As automations continues, concerns about job-losses are always on the forefront of debate. There is also the real cost to society with a smaller income tax revenue stream to fund things like roads and rail – the very things the transport industry relies on.

Ideas have been put forward for a robot tax to help subsidies this loss.

However these problems are dealt with in the future, it is clear for now that the inevitable march of the machines will continue.

Perhaps the solution lies balanced somewhere in the middle. With human operators and overseers able to quickly adapt to unforeseen problems, but with machines performing dangerous tasks for us, and with organizational systems augmented by computerized calculations.

The purpose of a container ship in the supply chain is in essence to connect the global economy. Container ships carry cargo across oceans, providing the main physical link between products produced internationally and the customers who use them. Casual observers may not realize just how important the container ship remains in the era of air freight. But even now, it's estimated that more than 80% of global goods are transported across oceans via ship. That indicates the international shipping industry continues to serve a vital purpose in the supply chain. Container ships go by many names, cargo ships, freighters, ocean liners, steam ships (whether they're steam powered or not), and sometimes simply skipping the space bar with containerships and steamships. We may jump between a few of these terms in this piece, but the gist remains the same.

How does cargo shipping work?

When it comes to transport of most goods, cargo shipping works around the container. That is, containers - typically of the 40' variety for ocean transport - are loaded at a manufacturing facility or distribution center. They can be moved from there via truck or rail - or a combination of the two - to a port. At the port, the container is transferred onto a ship to make the longest part of the cargo shipping journey - across the ocean, before the whole process is reversed at its destination. That means the container is transferred back onto truck or rail, or a mixture of both, or transloaded. Then the goods are distributed onto their final destination, which is eventually the consumer. Cargo ships do not always transport via container if their load involves certain types of freight, like coal or gas, but for our purposes we're focusing on those that do.

What do container ships carry?

Container ships carry just about any type of good one can think of, from food to clothing to fuel to furniture to electronics to vehicles to beauty supplies to household cleaners to...the list goes on. Container ships carry these goods internationally across oceans. Most goods are transported via shipping container - a step along the intermodal transportation chain - then transferred to trucks and/or rail. Some goods may require a bit more TLC, like perishable food requiring temperature-controlled (or reefer) transport or gas and oil requiring tankers.

What are the advantages of cargo ships?

The advantages of cargo ships are numerous, offering many reasons why they continue to be so heavily used. They include:

  • Cost
  • Flexibility
  • Capacity
  • Environmental friendliness

To expand on these points, let's start with cost. While air freight is obviously faster, it typically costs in the neighborhood of five times more than the sea-going option. It is important to note the most savings is realized the larger the load. Next, flexibility is great with ocean shipping, allowing for large loads, oddly sized items, heavy loads, hazardous materials and more. This relates to the follow-up, capacity, as the sheer size of container ships offer capabilities for more goods - with the ability to transport stacks of containers both above and below deck. 

And finally, another advantage is environmental friendliness. Studies show cargo ships are the most environmentally form of transport. Compared to planes, they're roughly 20 to 30 times better in terms of carbon footprint. A Defra study in The Guardian compares the carbon footprint for a two ton load going about 3,000 miles. Via small container ship it creates 150kg of CO2e, compared to 6,605kg of CO2e if the same load ships via air freight. 

What is the container shortage?

It is impossible to write about container ships in 2021 without mentioning the container shortage elephant in the room. In short, the pandemic-related pause on the economy followed by a roaring consumer-good restart placed containers at a premium. And the world has yet to catch up due to labor challenges, varying lockdown statuses, material shortages, and again, increased demand.

In fact, estimates have a few million containers sitting empty, away from ports. Ocean freight operators are trying to change that, by putting a ticking clock on the return of empty containers to ports with financial penalties attached to missed deadlines. And even for those fully compliant, the fees to use a container are up 125% or more in some circles. Not coincidentally, container lines are looking at record profits this year and next.

How to solve port congestion

While using a container ship offers many advantages, one major obstacle in need of solving is port congestion. Throughout the year, port congestion has reached unprecedented levels for a variety of reasons - including a trifecta of shortages: labor, containers, and warehouse space. Congestion has been especially bad at the major ports of Long Beach and Los Angeles, though there has been some reason for optimism lately. Solutions have included new queueing systems, increased 24 hour port activity, staggering shipments, and considering alternate ports of entry - though that's not without its own set of consequences.

If you're ready to take the next step, at InTek Freight & Logistics, we can help. Just tell us what you need and we'll discuss how our expertise can help with the unique shipping challenges your business faces. Rather do a bit more research first? View our Freight Guides for comprehensive articles and eBooks on all things freight and logistics.

 

How Does Logistics Container Work?

What is the purpose of a container ship in the supply chain