How do containers lock together

This would in turn overload their securing systems, which already have their hands full holding their own container stacks, and they would therefore also fail. The obvious consequence is a domino effect, such as the one seen recently on the the MSC Zoe.

However, the securing balance on our seesaw can also be disrupted by the cargo in the container itself. This is because the securing systems on board ships are calculated on the assumption that the dynamic behavior of the cargo is neutral. Static masses are assumed for the containers, and it is assumed that this mass always acts at the same point in the container. If a cargo weighing 30 tonnes is inadequately secured in a container, it will break loose in a rough sea and bang from side to side in the container.

This violent sideways motion has the same effect on our securing system as a wrecking ball on a house. The extent to which a ship rolls in the swell will also depend on its stability. The stability referred to here is the ability of a ship to right itself after an external force is applied, for instance as a result of swell. A ship with high stability will right itself again quickly, and a ship with less stability will right itself more slowly.

Too much or too little stability is bad, because high stability results in high acceleration, whereas inadequate stability could cause the ship to capsize. The securing systems of a container ship are designed according to longitudinal, lateral and vertical acceleration values, which are calculated using empirical formulas of the classification societies.

These formulas are based on swell statistics and transfer functions for ship behavior. Because container ships are still evolving in terms of size, speed and container stowage height, these formulas are also constantly being revised. However, they never show the worst case scenario, and instead represent assumptions where there is only a very low, but generally accepted level of probability that they will be exceeded.

The actual amount of acceleration caused by swell will depend on the characteristics of the ship and the swell itself.

As a rule, the larger the ship, the less likely it is to be caught in seas that will cause it to move violently. Unfortunately, there is an important exception to this rule in respect of rolling movements. This is known as resonance and works in the same way as children working a swing ever higher.

This results in large roll angles and large lateral acceleration. Yes, you can secure your container to the ground. We have 2 units available which will go under your container. These being our Weldable twist lock or the Boltable twist lock. The Weldable twist lock would be welded to a steel plate cast into your slab or footing.

The Boltable twist lock, as the name suggests, would be bolted down to your slab or footing and the container lowered on to the unit. Another option is our patented Side twist lock, which is placed in either the side or end hole or both of the Corner Castings and then bolted to the slab or footing.

This is done after the container is in place. There are a number of different ways and products to bolt a shipping container down. The most common is by using Boltable or Side twist locks with a concrete footings or piers. We have 4 different types of truck trailer twist locks available.

Depending upon your truck tray or trailer will determine which unit you require. Yes, you can. We have Container Trolleys and Container Castors available. These have different load ratings, so whether your container is empty or has something in it, we have a unit available for you.

Yes, if you require certification of the units, we do have the test certificates from our factory. We are the number one supplier of shipping container twist locks and container connection devices to the New Zealand market. Running out of space? Need to expand your storage options without moving? Invest in a storage container! Storage containers are a great investment to help protect your inventory, equipment or other valuables from thieves and most of the elements.

However, you may. Some folks would be happy. Petersburg St. Request a Quote. Request A Quote. How High Can Shipping Containers Be Stacked Back in the early days of shipping, before the sophistication of twist-locks and cells came about, cargo carriers were only allowed to stack boxes 5 or 6 high.