Holland Hydraulics B.V. has supplied a hydraulic system that is used for the emergency water barrier for the Noord-Zuid metro line in Amsterdam. Because of the merging of the existing metro station Central Station of the Oost-line and the new metro station Central Station of the Noord-Zuid-line, which crosses the primary water barrier with the IJ, an emergency water barrier had to be installed in the existing tunnel of the Oost-line.

The hydraulic system consists of a hydraulic power pack, 2 cylinders for the synchronization of the slide, 2 locking cylinders, 3 hydraulic manifolds and piping, installed on-site. The hydraulic unit is designed with 4 drive sets of 5.5kW with a double pump with a flow of 2 x 30L/Min. In order to increase the reliability of the system, the system is redundant and also equipped with a manual override. This makes it possible to manually lower the 50-ton slide into parallel in case of power failure.

The hydraulic cylinders used to control the slide have a bore of 220 mm and a stroke of 4700 mm. The locking cylinders have a bore of 63 mm and a stroke of 400 mm.

Holland Hydraulics provided the customer with advice, engineering, production, installation, commissioning and complete training of the complete system on site.