Handling without interruption |
Demag crane works round the clock in the steel trade
A double-girder overhead travelling crane supplied by Demag Cranes & Components is used for handling steel sheet and plate at the Hamburg branch of Blume Stahlservice GmbH. In addition to "gentle" handling of the heavy steel plate, the customer mainly requires a high level of availability for the crane, which is in continuous operation 24 hours, every day.
Established in 1955, and now specialised in selling flat steel products, Blume Stahlservice GmbH, Mülheim, is a subsidiary of Corus plc., London, one of the largest steel companies in the world. At its four German locations in Hamburg, Mülheim, Stuttgart and Zwickau, Blume handles some 400000 tonnes of steel per year. The locations are assigned to customers in local industry. The Hamburg branch is specialised in shipyards, such as Blohm & Voss, and the wind power generation industry, for example.
The double-girder overhead travelling crane supplied to Blume by Demag Cranes & Components has a load capacity of two times ten tonnes. The magnet spreader was already available and had to be used. It has a load capacity of two times eight tons. Both crabs on the crane can be controlled as either single units or together. The long and cross-travel motors are frequency inverter-fed to ensure smooth starting and braking, and thus to eliminate excessive sway of the very large metal plates.
The most important requirement for Blume is the high level of availability of the double-girder overhead travelling crane. According to Blume, this was also the main reason for the decision in favour of Demag as the supplier, since the manufacturer provided good references in the steel handling sector. As the heart of the entire installation, the crane is needed around the clock in three-shift operation, also for unloading railway wagons. In addition, Blume also requires a high crane capacity, since the the steel plates not only have to be stored and retrieved, but most of them also have to cut in line with customer orders by flame cutters in the adjacent processing centre. This means that handling operations have to be performed virtually without interruption. Furthermore, a considerable amount of sorting is also necessary for some 80 per cent of the steel plate in storage. The plates in the Hamburg store, which weigh 15 tonnes on average, cannot be stacked in dedicated piles due to their varying dimensions. In order to ensure the required high level of availability in the long term, Blume is expected to conclude a maintenance agreement with Demag.
The crane is operated either from a cabin or via radio control at floor level. For safety reasons, switchover from one control mode to the other is not controlled by a switch, and the crane operator has to reconnect the appropriate terminals in the cabin. The operator may enter the store when the crane is operated by radio control. Between the metal pates are aisles in which he can maintain a safe distance to the load. Cabin control is preferably used when trucks have to be loaded with goods weighing up to 17 tonnes, for example. The crane operator can view the inside of the truck and align the load exactly from above. In order to secure the load, positioning accuracy has to be within millimetres.
The highest priority is placed on safety, since the Corus Group specifies the highest safety standards for all of its subsidiaries worldwide. For this reason, Blume Stahlservice also considered it essential for all relevant employees to take part in a crane operator training course.
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Contact:
Corporate Communications
Demag Cranes & Components
Mr Christoph Kreutzenbeck
Tel. +49 (0) 211 / 7102-3907
