Liebherr-Transportation Systems has received a further order from Stadler US Inc., Salt Lake City, Utah (USA) for the supply of 72 dampers with integrated displacement sensor for FLIRT diesel-electric low-floor multiple units. Trinity Metro operates these on the TEXRail commuter rail line in Tarrant County, Texas, along a 43-km route between downtown Fort Worth and Dallas Fort Worth International Airport.
For the TEXRail project, a new pneumatic levelling system has been developed by Stadler which includes Liebherr's vertical dampers with displacement sensors. The damper design has already been deployed successfully in many hydraulic levelling systems.
Two of these special dampers are arranged vertically on each bogie. Each damper signals the piston position over the entire stroke. The Train Control Unit takes the signal from the damper and regulates by two magnet valves the air volume required in order to reliably adjust the required car level.
With the dampers developed and manufactured by Liebherr, this new technology not only reduces energy consumption on the vehicle - with significantly less compressed air having to be generated - but it also guarantees reliable position monitoring of the vehicle body. A further advantage is that a mechanical shift linkage for regulating the compressed air volume which might also have been damaged by icing or stone chipping is no longer required.