STAHL CraneSystems Wire Rope Hoists Defy Heat and Dust in Steel-Making Facility

Nedstaal produces high-quality steel for steel treatment companies. At its facility in Rotterdam, an in-house locomotive arrives every few minutes, bringing molds with red-hot, fresh-cast steel. The casting molds, or chill molds, are unloaded here to be cooled down, opened, cleaned and stored temporarily. Two grab cranes travel under the building’s ceiling and load and unload locomotives and lorries around the clock. At the center of all this is a robust and reliable crane featuring STAHL CraneSystems technology. 

Installed by CraneBuilders, a Dutch partner of STAHL CraneSystems, the 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 versatile German crane technology, the team was able to develop the ideal crane system for the customer.

Nedstaal’s core business is small, made-to-order batches of high-quality steel weighing 30 to 50 tons. Nedstaal is able to produce hundreds of different types of steel depending on the composition of the raw materials and the processing. Both the individually produced steel grades and the short delivery times are of crucial importance for the company’s success and depend on a high material throughput in the production chain. This calls for reliable technology.  

The crane 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 solution, extremely high forces act on the rope drum and cause the rope and rope guide to wear quickly. This causes short intervals between required maintenance intervals and unplanned downtimes.

“We worked together with STAHL CraneSystems and developed a low-wear solution with two wire rope hoists specially adapted to this application,” said CraneBuilders’ Marco Lindhout. “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,” said Lindhout.

A sophisticated rope bracing system at a set distance below the wire rope hoists makes this possible. “The customized rope reeving over several sheaves holds the load free of oscillations during travel and the angled ropes have a stabilizing effect,” Peter Kittsteiner, STAHL CraneSystems’ Area Sales Manager, explained. This also prevents stress on the rope drum caused by diagonal pull, for example. “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,” Lindhout said.

Steel production is energy-intensive, but Nedstaal tries to conserve resources wherever possible – this includes on the crane. The controls on this crane feed the energy produced by frequency inverters and brakes back into the grid, so the crane’s total energy consumption is reduced.

To enable the crane to function trouble-free in spite of the high build-up of dust, CraneBuilders used two AS 7 wire rope hoists from STAHL CraneSystems. The robust hoists are regarded as particularly reliable, as they are low-maintenance and have no trouble coping with high ambient temperatures and adverse conditions. The AS 7 was the best product for this project. STAHL CraneSystems was able to customize the wire rope hoists to the design, installation was simple, commissioning unproblematic, and the crane has been running since without incident – in spite of the thick layer of dust which frequently builds up on the crane.

The collaboration between CraneBuilders and STAHL CraneSystems yet again proved to be a success.