Those who visit Dubai cannot miss it: the Burj Khalifa. With its 828 metres height and iconic shape, it is the highest skyscraper in the world. The Burj Khalifa towers gracefully above the skyline of the Gulf region.
What many people do not know is that when they designed the Burj Khalifa, the architects Skidmore, Owings & Merril were inspired by the leaves of the Hymenocallis, a local desert rose. The shape of the tower is therefore entirely organic. The entire facade consists of curved shapes.
The Burj Khalifa is characterised by a magnificent glass façade, a window area of 83,600 m² and a total exterior area of 111,500 m². This is equivalent to 18 football fields! Given Dubai's aggressive sea climate with its high humidity and desert storms, the façade will have to be well maintained. That is quite a job at the Burj Khalifa and it is still done by hand! One round of window cleaning takes an estimated 3 to 4 months.
In order to facilitate the maintenance of the façade, fifteen mobile units, the so-called Building Maintenance Units (BMU), have been installed throughout the tower. These units are attached to the tubes surrounding the tower. At five different levels, nine curved tubes are attached to the façade all around the tower. Seven of these are decorative. The other two are heavier and stronger and also serve as rails for the BMU unit that lowers the platform for the window washers. In this way, every square metre of the tower's surface can be reached.
The curved tubes, both decorative and functional, were produced by Kersten. An exceptionally large assignment that took us 1.5 years to complete. Plus a great honour to be able to contribute to the highest tower on earth and also the most prestigious assignment we had ever worked on.
In total, over 1,200 polished stainless steel (316L) tubes with a diameter of 273 mm and a total length of 11,000 metres were supplied by our client. The tubes with a decorative function had a wall thickness of 3 mm, the tubes to which the maintenance units were connected had a wall thickness of 8 and 12.5 mm.
Kersten bent all the tubes to the required radius and then cut them to size in 3,870 sections with a length of 180-300 cm. Slots were cut into the tubes with a cutting robot and brackets were welded to the tubes. A very precise process because everything had to be exactly in the right place in relation to the mounting point on the tower. The surface requirements were very strict, so the tubes were professionally polished again after bending and machining.
After the curved parts were ready to be installed, they were carefully packed so that no damage could occur during the transportation from Kersten in Wanssum (Netherlands) to Dubai. It required 50 sea containers to ship the assembled segments to Dubai. There, they were installed on the tower by our client in perfect condition.