The city of Madrid, Spain, faces many of the same challenges as any large city. One of these, of course, is managing vehicle traffic. To deal with the city’s increasing traffic, Madrid’s Madrillien Council approved a project to construct 56-km of tunnels around the city. This allows traffic to more easily bypass the city — to reduce congestion — while also providing greater access between major traffic routes.85 escape

This huge construction project was completed last year and included refurbishing Spain’s heavily traveled M30 inner-ring road motorway and rerouting major sections of it through the new tunnels. Of course, safety and security were high priorities, so the plan included 85 emergency escape exits to be installed in strategic locations.

GS-Hydro Spain developed and assembled the 85 hydraulic systems that open emergency exits from the tunnels to the surface. These systems were delivered on a turnkey basis.

Because the exit doors are horizontal when closed, the hydraulic systems had to be sized to lift loads as heavy as 6300 kg – to deal with situations such as a vehicle or other heavy object left on top of the door at the surface. Specifications called for the doors to swivel open 45º in 30 sec.

To meet these requirements, each exit uses a pair of hydraulic cylinders (63-mm bore, 850 mm stroke). A 2800-kW, 400-V electric motor drives a 160-bar gear pump that supplies 15 l/min. to the system. As a backup to the pump, a piston-type hydraulic accumulator stores 60 l of pressurized fluid. The system is piped with DIN 2391 chromium-free seamless steel tubing and DIN 2353 fittings provided by GS Hydro.

The doors can be opened either electrically or manually (by the accumulator). The system can be operated locally or remotely from a central control station. In addition, a PLC includes a complete system (processing more than 60 signals) for operation monitoring and preventive maintenance. Headquartered in Hmeenlinna,

Finland, GS Hydro provides nonwelded piping systems and modules, including design and engineering; materials and components; and prefabrication and on-site services, such as installation, flushing, testing, and documentation.

For more information, contact GSHydro at Or call its U. S. headquarters in Houston at (281) 209-1000.

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