Tensorex® for Schiphol Airport Rail Tunnel

The rail infrastructure in the Netherlands has several crucial junctions, one of which is the Schiphol Rail Tunnel, providing access to Schiphol Airport for a growing number of commuters, business travelers, and holidaymakers. Reliable transportation is of paramount importance here, so every effort is made to prevent disruptions and delays. Therefore, higher demands are placed on materials for the overhead lines and power supply, with a preference for materials that require minimal maintenance.

During its construction in 1975, gas disconnectors were installed, mainly because they were space-saving. Recently, the gas disconnectors in the first tunnel tube had to be replaced because they no longer met the stringent requirements of the infrastructure manager, ProRail.

Gas Disconnectors: Inadequate Performance

The gas disconnectors suffered from oil leakage and a decrease in gas pressure, resulting in a reduction of the required constant tension force. This necessitated extra inspections and, consequently, a lot of maintenance. In short, time-consuming equipment with mediocre performance. Engineering firm Movares Nederland was commissioned by ProRail to provide technical guidance for the replacement of the gas disconnectors and sought technical advice from Seher for an alternative product.

Tensorex® Spring Tensioners: Ideal for Schiphol Rail Tunnel

Seher recommended Pfisterer Milaan's Tensorex® spring tensioners. This compact product was highly suitable for the limited space in the tunnel. In consultation with Movares, Pfisterer, and Seher, the standard version of Tensorex® was modified so that both the support cable and the catenary wire could be tensioned within the available space. Tensorex® spring tensioners function 100% mechanically and require no maintenance. ProRail approved and received the product with complete satisfaction. However, the biggest challenge was yet to come.

Swift Replacement

The available time for the replacement works was extremely limited. Interruptions in the train schedule had to be minimized, especially transportation to and from Schiphol. Therefore, the gas disconnectors had to be replaced at night, with a strict deadline in the early morning to ensure uninterrupted train passage. A total of 35 Tensorex® spring tensioners needed replacement, with two units per night. It was an urgent and sizable task, where on-site instruction for the Strukton Railinfra technicians and flawless planning of assembly and logistics were critical. Top-quality performance was ensured on all fronts.