Dortmund/Zeebrugge. Europe's largest movable lift-and-turn bridge is located in a town with barely 4,000 inhabitants. The 400-meter-long "Verbindingsbrug" is located in the Belgian Port of Antwerp-Bruges. The middle section can be turned through 90 degrees over a length of 130 meters within a few minutes. The reliable and smooth rotation is made possible by a roller bearing from thyssenkrupp rothe erde.
The population of the former fishing village bears no relation to the size and importance of today's Port of Antwerp-Bruges: it is the second-largest port in Europe after Rotterdam and ranks 13th in the world in terms of cargo handling. Covering an area of 14,300 hectares, or about 20,800 soccer pitches, the Flemish coast handles around 300 million tons a year. The Port of Antwerp-Bruges creates 160,000 jobs at 1400 companies and is also the arrival and departure point for 700,000 cruise passengers per year and 2,800 ferry passengers per day.
Bridge keeps traffic flowing in the world's largest car transhipment port
However, the port's greatest relevance worldwide is as a hub for the automotive industry: "Every year, Port of Antwerp-Bruges transships around three million cars, making it the largest 'car port' in the world," reports Bert Vandendorpe, project engineer at the Port of Antwerp-Bruges. Most of the cars are delivered by huge special ships to the so-called Voorhaven. From here, the goods travel along a total of around 42 kilometers of roads in the port area to parking and collection points and from there to the European markets. " Swift onward transport is important to maintain the seamless flow of goods, and the smoothest possible logistics within the port are crucial," says Bert Vandendorpe.
Slewing bearing moves 2,200 tonnes of steel and concrete
To ensure this, roads and of course bridges are of enormous importance. In 2020, the predecessor bridge of the Verbindingsbrug reached its load limits and a new construction became inevitable . Since it was located at a central point between the aft and inland harbors, the construction had to had to accommodate shipping traffic. The solution: a swing bridge, partly because of increasing traffic, but also in unprecedented dimensions. The bridge is opened and closed between five and 30 times, each taking just under three minutes. This places special demands, not only on the bridge itself but also on the mechanical construction: "The rotating part of the bridge is 130 meters long and weighs 2,200 tonnes," explains Carsten Wiemann, Account Manager at thyssenkrupp rothe erde. Together with the engineering department, Carsten Wiemann is responsible for the design of the roller bearing, a three-row roller bearing with external teeth, which enables the movement of the bridge. For such applications, thyssenkrupp rothe erde calculates the bearings individually, taking into account the service life requirements. The result is a bearing with a diameter of seven and a half meters and a weight of 17.6 tons. The dead weight of the bridge alone was not enough: "We had the specification that the construction could withstand an additional load of up to 500 tons if, for example, large mobile cranes had to cross the bridge," recalls Carsten Wiemann. The people who work in the port were also considered during this process: "A cycle path was also included in the planning of the bridge, so the different workplaces are easier and quicker to reach."
Operational safety despite salt water and harsh North Sea climate
Unlike other movable bridges, only one part of this swing bridge is movable. This has the advantage that the mechanics and drive are only needed once. This not only reduces the complexity of the construction but also facilitates maintenance and servicing, since both the motor and the mechanics are freely accessible in one place. The disadvantage: In order to move a single bridge part, a significantly higher load is required, which has to be borne by a single bearing: "When the bridge is opened, it is first lifted by a few centimeters, and from this point on, the full load is already on the bearing," explains Carsten Wiemann. Only then does the bridge begin to rotate. In the future, ships with a length of up to 55 meters will pass through the Verbindingsbrug, so the movable bridge section had to be designed accordingly. Harsh weather conditions and the aggressive salt water of the North Sea are additional challenges: "In this project, absolute reliability at all times under extreme loads is crucial. In the event of a failure, part of the port would be at a standstill. With our three-row roller slewing ring, we offer exactly the right answer to these challenges, combining the ability to handle large loads with a long service life."