Cílem společnosti je nabízet kompletní řešení projektů, které budou odpovídat nejmodernějšímu stavu techniky a na jejichž konci bude spokojený zákazník a uživatel.
The aim of the company is to offer completely packaged projects with solutions that are in harmony with the state-of-the-art of the technology with a satisfied customer and user at the end.
Das Ziel der Gesellschaft ist, die komplette Abwicklung der Projekte anzubieten, die dem neuesten Stand der Technik entspricht, um am Ende zufriedene Kunden und Benutzer zu bekommen.
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Resistance to Derailment


Tests of resistance of railway vehicles to derailment are performed either in the testing lab of the VÚKV a.s. at Cerhenice or in the place specified by the client (for example in the manufacturing plant or the depot).

The aim of the test is to prove that a vehicle shall not derail by excessive wheel unloading when negotiating normal variations in track twist.

One of the equipments used by the VÚKV a.s. for these tests is the computer-controlled mobile wheel unloading test bench (with hydraulic system) In the course of the test carried out on this mobile equipment the wheel force values are monitored with the sensors together with the vertical displacement of the wheels. The characteristic properties and advantages of the mobile test bench of the VÚKV a.s. include:

  • The test may be performed in the manufacturing plant or depot (saves time for formalities and transport of the vehicle to the testing lab),
  • Measurements may be performed for vehicles of all usual gauges (0.7 – 1.7 m),
  • Simulations of the vehicle pass through super-elevation ramp may be performed,
  • Standard and untypical railway track twists can be simulated,
  • The test can be carried out with special vehicles (e.g. bi-modal vehicles, trams),
  • The tests do not affect the suspension of the vehicles and no special parts need to be manufactured for the purpose of the testing (such as suspension inserts).


Tests of resistance of railway vehicles to derailment are conducted in compliance with:

  • ČSN EN 14363,
  • ERRI B55 RP8,
  • Specific requirements of the approval authorities or operators.


The VÚKV a.s. testing laboratory further measures torsional stiffness of vehicle underframe (carbody) according to ERRI B 12/DT 135.

The test outputs include but are not limited to:

  • Diagrams of wheel forces for all wheels and possible combinations of twists of track,
  • Values of wheel forces on horizontal rail with exclusion of the effect of the suspension hysteresis,
  • The value of torsional stiffness ct*,
  • Other parameter values, such as:
    • Displacements within suspension,
    • Pressures in air springs,
    • Movements of the carbody,
    • Stresses on suspension elements,
    • Time responses of suspension control.


Wheel unloading measurement conducted during the test of resistance to derailment on the VUKV a.s. mobile test bench can be conveniently combined with the measurement of sway coefficient and roll center height. Thanks to that all the tests can be performed within a single manipulation of the tested vehicle at the test bench, which saves costs of the testing.