Crucial rail-wheel design for main and emergency drive retaining sluice Afsluitdijk

For the main and emergency drive of the floodgate at Kornwerderzand, the Belgian company Demako has designed a rail-wheel construction. A crucial part of the floodgate. Managing director Thomas Beckx explains how they arrived at the final design. 

"For the renewal of the Afsluitdijk, we had two orders from construction consortium Levvel, which is carrying out the work on behalf of Rijkswaterstaat," Thomas explains. "First of all, the realization of the main drive for the floodgate at Kornwerderzand including the under rollers and rails. We also built the emergency drive for the floodgate. The floodgate has a large steel door of 1,000 tons, 58 meters long, 9 meters wide and 14 meters high. For this, we used a rail-wheel design. The door is pulled open and closed by a cable work. The door itself rests on two under rollers on the bottom of the passageway that act as wagon sets traveling on rails. Given the weight and required design life, special extra-hard and tough steel was chosen for the tracks that are fully supported by steel sections."

Proven design

Demako is a specialist in the engineering of mechanical drives for bridges, locks and other structures. This assignment is therefore right up the company's alley. "We have a lot of knowledge thanks in part to the variety of exceptional projects we are carrying out, such as the third column at the Beatrix locks, the Kieldrecht lock in Antwerp and the new Connecting Bridge in Zeebrugge. An important advantage is that we have everything in-house to realize a project from A to Z: our own engineering department, a welding and machine hall and in-house assembly. Thanks to this experience in building many types of structures, we can apply the various working methods, systems and principles within the Afsluitdijk project. In other words, we can therefore introduce new systems that already have a proven track record in other projects, such as in this case the rail-wheel design." Construction of the floodgate at Kornwerderzand is nearing completion and all tests, including the important operational test, have gone well. "For us the confirmation that the system works the way we conceived it too."

World of difference

Sustainability and safety aspects play an important role in both the design process and implementation. These include efforts to recycle consumables and maintenance-friendliness. "For the long-term use of the lock, we are trying to ensure that it is as maintenance-friendly as possible. We already take this into account in the design. The choice of a maintenance-free sleeve bearing or ball bearing, for example, can make a world of difference in terms of cost, but certainly also in terms of consumption and thus environmental impact. Safety is also already included in the design process. And on our yard itself, inspections, toolboxes and Last Minute Risk Assessments (LMRA) are carried out."

'Best for project' solutions

Thomas looks back with satisfaction on the cooperation with the design and implementation team of Levvel and HSM. "Our strength lies in thinking across disciplines. With the design team of Levvel and HSM, we set to work. In doing so, we continuously looked for 'best for project' solutions. Everyone involved was very constructive in meeting challenges. As far as Demako is concerned, we can therefore certainly speak of a successful collaboration with constructive discussions."