Demag gantry cranes in outdoor operation

Customer

With a production capacity of some 2 million tons per year, Dillinger Hütte is the largest heavy-plate steel plant in Europe. Lengths of up to 40 m, widths of more than 5 m and thicknesses of up to 600 mm are no rarity at its German steel location in the Saarland, which is steeped in tradition. Its main customers are from the construction industry – many architectural icons have been built with Dillinger heavy plate all over the world – and the plant engineering sector. Its product range includes special heavy-plate products (with corresponding certificates and approvals) for the construction of pipelines and facilities in the oil and gas industry. Dillinger operates its own sales and storage locations all over the world. Up to 3000 tonnes of steel are handled at the location in Dubai every month.

Requirement

Dillinger Middle East is expanding and extending its storage area in Jebel Ali/Dubai. There is demand for both heavy plate “made in Germany” in structural engineering as well as for special types of steel, e.g. with Saudi Aramco certification. The company had already purchased Demag portal cranes for its outdoor store in 2004 and 2009. A third portal crane was then needed for a new outdoor storage area.

The specifications included: 2 x 16,000 kg load capacity, 28 m span, hook path up to 6 metres, very rugged design with high availability even under unfavourable conditions (operation outdoors, temperatures from -10 to +55oC with strong day-/night-time fluctuations, sensitive positioning and various safety functions). Spreaders with load-lifting magnets are used as load handling attachments.

Solution

For this application, the Demag engineers designed a double-girder portal crane from the ZVPE range, also equipped with DRS wheel blocks and DH hoist units.

The DRS wheel blocks on which the portal crane travels demonstrate their suitability for special, and sometimes spectacular applications all over the world every day – for example on mobile roof elements in stadiums or in heavy-duty transfer carriages. The DH hoist units were also developed for heavy-duty applications, as were their conical-rotor motors from Demag’s own production. The speeds of the long and cross-travel drives are infinitely variable, the crane can be conveniently operated by radio control.

The third portal crane has already been in operation for some time and – exactly like the two older Demag cranes – has been running to the complete satisfaction of Dillinger Middle East.

Technology

Hoist units from the DH range can be used for a wide variety of applications and offer a number of special technical features that enable loads to be handled reliably, also for demanding requirements. Thanks to their mechanical microspeeds and conicalrotor brake motors, they can also be operated at high ambient temperatures with a high number of starts/stops and high duty factor. At the same time, mechanical microspeeds ensure highly precise positioning.

A further design feature that will ensure a long service life of the hoist unit, also under unfavourable conditions, is the performance and transmission ratio provided by a high-quality planetary gearbox, which is protected inside the rope drum. Power distribution within the gearbox spreads the load and thus increases the service life of the hoist unit.