Stahl CraneSystems collaborates with CraneBuilders on steel project

The client produces high-quality steel for steel treatment companies, with its core business centred on made-to-order small batches of 30 to 50 tonnes.

With the in-house locomotive arrives every few minutes, it brings moulds with red-hot, fresh-cast steel, while the casting moulds, or chill moulds, are unloaded to cool down, opened, cleaned and stored temporarily.

Two grab cranes, installed by the lifting manufacturers, operate under the building's ceiling and load and unload locomotives and lorries around the clock.

René Rohde, CraneBuilders' project manager explained: "Nedstaal needed a particularly robust and reliable crane in this environment. Our crane system works with STAHL CraneSystems wire rope hoists and a grab with an off-standard rope bracing system.

"By working together and making use of the versatile German crane technology we were able to develop the ideal crane system for our customer."

Nedstaal produces high-quality steel for steel treatment companies. Its core business is made-to-order small batches of 30 to 50 tonnes. Steel is not just steel: Nedstaal is able to produce hundreds of different types of steel depending on the composition of the raw materials and the processing..

The newly-installed crane in the front section of the building is equipped with a grab for picking up steel cylinders safely and quickly. The grab is lifted and lowered by two wire rope hoists mounted on a double rail crab.

In this type of grab, extremely high forces act on the rope drum and cause the rope and rope guide to wear quickly. Short maintenance intervals and unplanned downtimes would be the result of this.

CraneBuilders' Marco Lindhout, explained: ""We worked together with STAHL CraneSystems and developed a low-wear solution with two wire rope hoists specially adapted to this application.

"Our design means that the grab can be moved absolutely vertical and without rotating, even if there is a slight asynchronism or one of the hoists comes to a stop. A sophisticated rope bracing system at a set distance below the wire rope hoists makes this possible."

According to Stahl CraneSystems' area sales manager Peter Kittsteiner, who was involved in developing the solution, the customised rope reeving over several sheaves holds the load free of oscillations during travel and the angled ropes have a stabilising effect.

"This also avoids stress on the rope drum caused for example by diagonal pull. Sometimes you don't need that much technology - a lot of problems can be solved intelligently and extremely efficiently with plenty of experience and the right idea," CraneBuilders' Lindhout added.

For the crane to function trouble-free in spite of the high build-up of dust, CraneBuilders employed two AS 7 wire rope hoists from Stahl CraneSystems.

These hoists are regarded as particularly reliable, they are low-maintenance and have no trouble coping with high ambient temperatures and adverse conditions.

Rohde added: "The AS 7 was the best product for this project. STAHL CraneSystems was able to customise the wire rope hoists for our design, installation was simple, commissioning unproblematic, and the crane has been running since without incident - in spite of the thick layer of dust which has built up on the crane in just a few weeks."