In the beginning, scepticism prevailed. Today, however, the port operator is glad that its bulk crane for scrap handling is equipped with an energy chain solution. Despite the very harsh operating conditions, his system has been running for more than two years in wind and weather without any complaints. And when a new investment is due, they are certain that the choice will once again fall on a crane with a pre-assembled energy supply system including a robust stainless steel trough system.
At the Rhine port of Kehl, the Künz crane is used to transfer scrap of various qualities from railway wagons to the storage yard. From here it goes to the steelworks by ship at a later date. The crane facility, which is equipped with either a clamshell bucket, a polyp bucket or a magnet, depending on the requirements, places high demands on the technology. In contrast to container handling, the crane is permanently jolted very strongly when the scrap is cut loose. For example, T-girders or other connected lumps of scrap protrude from the grab. On top of that, it is permanently overcrowded. The whole crane is constantly loaded. Both the energy supply system and the guide trough have to withstand strong and most severe vibrations without being damaged. There may even be deformations that have to be compensated time and again.
The crane system is in use at all times of the year," explains the Master Electrician, Uwe Woltersdorf. "This means that it has to withstand all temperature fluctuations
The pre-assembled readychain energy supply systems are used in the bulk crane over a travel distance of 109 m. Specifically, this is the roller energy chain 4040RHD, which is particularly suitable for heavy-duty use outdoors. In this system, the feeding point is located in the middle of the travel. In addition, robust shielded chainflex special cables, single cores for power supply as well as control, bus and fibre optic cables guarantee functional reliability. Their TPE outer jacket covers temperature ranges from -35 to +100 °C and thus meets all weather-related requirements 365 days a year.
The scope of delivery also includes corrosion-free guide troughs made of stainless steel, which are intended to support the smooth and low-friction operation of the energy chain. Further special solutions round off the overall system: a customised enclosure protects the chain and cables from extreme weather conditions. And a floating moving end takes care of the necessary tolerance compensation from the chain system to the trolley. This ensures the greatest possible protection.
The cooperation between the port operator Kehl, the crane manufacturer Künz and the energy chain supplier igus worked very well during the project planning and construction phase. "In consultation with us the concrete installation situation was clarified on site," reports Uwe Woltersdorf. "In addition, we received detailed drawing documentation from igus. " The pre-assembled energy supply system arrived on site exactly on the agreed date and was installed under the direction of the crane builder. The electro-technical approval was then carried out with the involvement of the operator in cooperation with the energy chain supplier and the crane builder. "The installation quality was right," says the master electrician. "The energy chain system worked immediately. "
Since one does not want downtimes and cannot afford them, the next crane will probably have an energy chain system again. Uli Stichler: "Their technical and economic advantages have convinced us so far. And since we also assume a long service life based on experience, the decision for this energy supply solution was definitely worthwhile for us. “