semi-automatic twistlock

Twistlocks have been around since the 1950s as the safest and most effective way to secure containers on ships. Semi-automatic twistlocks make this process even easier as they lock automatically when a container is placed on the ship, but they are still secure as they require manual unlocking when it is time to release the container. This is especially useful when loading containers at a height, as it means that twist locks can be attached and locking mechanisms pre-loaded on the ground.

How to Use Semi-Automatic Twistlocks

To fit the semi-automatic lock to the container quay-side and pre-load it for automatic lock, twist the lower cone of the lock in an anti-clockwise direction until the upper cone is in an open position. Insert the upper cone into the open mouth of the corner casting of the container. Release the lower cone by pulling the handle out and up until it is in a centre horizontal position. This will cause the upper cone to lock, securing its connection with the container. Ensure that the lock is facing the right direction so that its mechanism is accessible during unloading.

When the container with semi-automatic lock is lowered into the top corner casting of another container, the lower cone will automatically twist into place and lock under the weight of the container.

In order to open the twist lock for container removal, twist the handle to the right and pull downwards. This will unlock the lower cone so that the container can be handled by the spreader that will be used to lift the containers from the ship. With the handle open in this way the shock load from the spreader will not cause the semi-automatic lock to relock.

Emergency tools are available to release the lock if it has accidentally been mounted backwards and the unlocking mechanism is not accessible.

Once the container is quay-side, to detach the lock from the container, pull the handle, which will turn to upper cone to the open position and allow it to be removed.

Features of a Good Semi-Automatic Twistlock

A good quality semi-automatic twistlock should include a number of features, all of which are present in the semi-automatic twistlocks provided by Counter Lock.

  • It should meet ISO strength requirements and other specifications.
  • The safety lock pin of the twist lock should be properly secured and never fall down from the container.
  • It should have an easy unlocking mechanism allowing the container to be released quickly and easily.
  • It should be straightforward to check whether the twist lock is opened or closed from the position of the handle.
  • It should feature shock absorbers to protect the handle against mechanical shock.
  • It should be compatible with both hinged head and fixed head lashing rods.
  • The design should be symmetrical so that it can be used upside down when required.
  • It should be easy to maintain, assemble and disassemble.

Semi-Automatic Twistlock Maintenance and Repair

Semi-automatic twist locks should be inspected and cleaned on a regular basis to ensure that they are safe to use. A basic inspection should include checking the mechanism and spring action as well as greasing all removable parts.

If during maintenance the cones of the lock are found to be damaged, the lock should not be used again. If a problem is with the wire, handle or bolts, these can easily be replaced.

Semi-Automatic Twistlock Supplier

Here at Ocean Link we are the leading container lock supplier worldwide. Our expert staff can advise on exactly which type of container lock offers the best security and the best value for your particular needs. While our head offices are in Australia, we can ship products to ports around the world. We currently ship to the United States, Australia, Europe and China.

Ports in the United States

There are currently approximately 360 active ports in the United States, and many of them number among the busiest in the world. The Port of Los Angeles located in San Pedro Bay, California is the largest on the west coast and is responsible for the majority of transpacific trade. On the east coast the Port of New York and New Jersey is the largest, offering access to one of the most concentrated consumer markets in the world. The ports of Savannah in Georgia, of Seattle and Tacoma in Washington state, and of Huston in Texas are some of the country’s other leading US ports.

We serve all major ports in the US.

Ports in Australia

Despite its relatively modest population, Australia is serviced by around 50 ports. The largest ports are unsurprisingly in Sydney and Melbourne, but the third largest port, in Brisbane, is also the fastest growing container port in the country. We serve all major ports in Australia, including Sydney, Melbourne and Brisbane.

Ports in Romania

We serve all major ports in Romania.

Romania is services by 25 ports located in the Black Sea, the Danube Black Sea Canal and the Danube River. The Port of Constanta is the largest on the Black Sea, the largest in Romania, and the 17th largest in Europe.

Ports in France

France is served by more than 330 ports. The Marseille Fos Port is the country’s busiest handing 88 million tons of cargo in 2011. La Havre follows closely receiving 75 million tonnes of cargo in the same year, but is in fact the largest container port in the country.

We serve most ports in France.

Port of Hong Kong

We serve the port of Hong Kong.

While Hong Kong’s small size means that it is served by only one port, it is one of the busiest in the world in terms of all three main categories: shipping movement, cargo handled, and passengers carried. Its location on the South China Sea and the naturally deep waters of Lake Victoria provide ideal shipping conditions.

Ports in China

China has 34 major ports, but over 2,000 minor ports spread across the country. We serve most Chinese ports, including the five busiest ports – ports of Shanghai (the world’s busiest container port), Shenzhen, Ningbo, Qingdao and Guangzhou.