When heavy cargo at the Port of Hamburg can only reach the ship over the water, this requires the floating cranes of Hamburger Hafen und Logistik AG (HHLA). They first safely lift ship propellors or trains onto pontoons and then onto the ship.

The two cranes that are still in use have been doing this work for a long time now. To be precise, HHLA III commenced service back in 1941. It initially helped in the construction of warships. After that, it aided in the reconstruction of the destroyed port, where the quantity and sizes of the goods handled soon increased again. As the only floating crane that could lift 100 tonnes,

HHLA III was kept busy with a heavy workload. For this reason, in 1957 the Department for River and Port Construction commissioned the construction of a new floating crane with a lifting capacity of 200 tonnes. The crane operates today as HHLA IV.

HHLA IV can lift

up to 200 tonnes

and itself weighs
2,750 tonnes.

In the 1960s, ownership of the floating cranes – or simply cranes as we like to call them at the port – was transferred to HHLA. They work as freely rotatable double-jib luffing cranes, and their stable frame ensures horizontal load control. The taller HHLA III can “only” lift 100 tonnes, but at 76 metres in height, it is able to carry loads over a lifting path of 48 metres.

As the youngest crane, HHLA IV has to handle the heaviest packaging units at the port. The more compact giant can lift up to 200 tonnes and itself weighs 2,750 tonnes. Nevertheless, the rectangular pontoon can still be controlled with millimetre precision even when fully laden. Depth-adjustable blades are situated

beneath the propellors of the port and starboard engines, which can perform fine course corrections with the slightest thrust.

To ensure things keep running smoothly over the coming years, HHLA IV was retrofitted last year. “This is the first major retrofit for HHLA IV after seven decades in use,” says Stephan Fröhlich, head of floating cranes at Hamburger Hafen und Logistic AG (HHLA), adding: “The project is based on the original construction and circuit diagrams from the 1950s. This work should ensure at least another 15 years of service.” The crane has already celebrated its 80th birthday – a prime example of sustainability in practice at HHLA. After all, the construction of a new crane would involve tremendously high energy and material costs for such a large piece of equipment.

The scaffolded and film-wrapped crane body gives away the extensive work being carried out on the special vessel. HHLA III had already removed the cantilever together with mobile cranes in summer 2023. At the time, the movable construction was deposited at the quay in five segments.

The lower link arm lay under a tent with a corrugated iron roof. Protected in the mobile hall, the old steel construction underwent thorough reconditioning. The signs of use and the old paint were removed before necessary repairs were carried out and new corrosion protection applied. The opportunity will also be taken to replace the massive bearings. This work is being carried out on the tower of the self-driving pontoon, protected under cover.

All the effort in reconditioning the crane is worthwhile for HHLA, since the construction dating back to the mid- 20th century is still ideally suited to certain tasks at the port. Heavy loads with oversized weights and dimensions are still transhipped at the all-purpose port. This includes ship propellors, which can weigh more than 100 tonnes, as well as the parts of large offshore wind farms. This is where the floating cranes are in their element. They can lift the heaviest loads with extreme flexibility, transport them autonomously and securely stow them on huge container ships. For really big jobs, the cranes can even work in tandem. “The fact that our cranes can turn 360 degrees is almost unmatched in heavy cargo handling at ports nowadays,” says Heinrich Proes, outlining the special capabilities of the historic cranes.

This is possible thanks to the classic design: a conical tower in steel framework is firmly attached to the pontoon, which is enveloped by the freely rotatable structure like a hood. The upper section houses the bearings of the cantilever structure with the lower link arm and the upper link arm. The overall form is rounded off by the cantilever tip at the front and the counterbalance at the rear. In combination, the lower rotating assembly and the tip of the supporting structure absorb the vertical and horizontal forces. A whole battery of slip rings in the heart of the structure ensure electrical energy and control signals are transmitted between the structure and the vessel.

A similar setup can be seen with HHLA III. The floating crane was reconditioned a little earlier in 2023. At the beginning of the year, the high cantilever that towers above most of the port facilities was disassembled, while the rest was sandblasted and painted. Newly manufactured parts arrived from Poland by ship, the heaviest of which weighed 65 tonnes. The upper and lower link arms, cantilever tip and swing arm were unloaded with the help of HHLA IV. The heavy puzzle pieces had to be put back together and assembled on land with mobile cranes, including all wheels, bearings, ladders and steel cables, each of which is four centimetres thick and 500 metres long.

In February, before an audience of inspectors from Germanischer Lloyd and the trade association, the 71-yearold machine then lifted 110 tonnes – ten tonnes more than the normal maximum weight – without any groaning. It continues to meet all the safety requirements. Germanischer Lloyd monitored every step of the repairs and checked all the welding seams and cables.

Soon, the old machines will once again stand together next to huge container ships and load cargo too heavy for gantry cranes. There is plenty of space at Hachmannkai for storing the packaging units. “The location is ideal,” notes Fröhlich. “The cranes are situated next to HHLA Container Terminal Tollerort, where we often load heavy cargo onto container ships. Blohm & Voss is located right across from them at the offshore terminal, as is MAN which installs ship diesel engines. Both are customers.”

Take a look at the oldest floating crane

Two 30-tonners still belonged to the fleet of floating cranes until the 1980s: HHLA I and HHLA II. They were built by world-class Hamburg companies in 1928, neither of which exist today: Deutscher Werft and the crane builder Kampnagel. In 1986, HHLA I was handed over to Ovelgönne museum harbour, where it can still be visited to this day. Back then it was the oldest active crane at the Port of Hamburg and it had achieved more than 100,000 hours of operation. Following extensive restoration work, it was most recently seen at the port’s anniversary parade.