Kaup's giant rotator in action

Kaup has developed, produced and supplied two of the largest attachments for forklift trucks in the world to a steel works in the Netherlands.

The largest rotators in Europe have been in use there for several months and have completed thousands of load cycles to empty extremely heavy slag containers.

The dimensions of the attachments created several challenges for designers and engineers at Kaup. Although the engineering company from Aschaffenburg is familiar with special designs and large dimensions, 13 T empty weight, 4,600 mm width, 3,475 mm height and 45 T load capacity are not commonplace, even in the lower Main valley in Bavaria. Nevertheless, the attachment producer successfully delivered the huge rotators in record time - less than a year from initial contact to installation.

Alongside the sheer size and the tight schedule, the project confronted the Kaup team with some interesting challenges, according to designer Bernd Ackermann. "The adapted flanged couplings and the completely new welded fitting were two decisive factors, because we also hadn't designed anything like this before.

"But after about 10 weeks' design time and permanent coordination with the customer, Kaup was able to begin with the challenging production process. For example, the forks had to be welded manually to the huge base plate in a laborious and complex process. Before the challenging dispatch of the huge machines, there were additionally intensive tests of both 60T391 on test rigs built especially for this project."

The rotators were commissioned for IJmuiden in the province of North Holland. The area is known for steel product and faced the challenge of removing slag, a by-product used, for example, as the subgrade in road construction.

In the past, the slag was collected in large ladles and moved to the edge of the site. There, massive gantry cranes emptied the containers in the open air so that the slag could cool before being processed. The disadvantage of this method was the production of huge amounts of graphite dust, which endangered the inhabitants of the neighbouring community of Wijk aan Zee.

The customer wanted Kaup to not only make the slag disposal cleaner, but also redesign it to become more modern and fit for the future. Skips were introduced to replace the traditional ladles. However, the 23 T load presented a challenge for traditional forklifts and attachments.

The solution was two special rotators designed for the task and weighing over 13 T. They were fitted to huge Kalmar forklifts.

In the new process, a forklift picks up the full skips and moves them in sequence into a roofed, open storage building. The full, still-hot containers stay there to cool, so processing is possible. When the load has cooled, the hydraulics of the big Kalmar drive the 60T391, which rotates the skip for unloading. The rotator then returns the empty skip to its original position, ready for a new loading cycle.