
Torsional vibration of wheelsets presents a challenge in rail transport. The torsional vibration of a wheelset reduces traction and leads to increased wear, also termed “rolling contact fatigue”. Normal torsion stress from rolling contact is brought about by drive torque, brake torque or load torque. Along with torsion stress due to technical aspects relating to vehicle operation, wheelsets are also subject to natural vibration.
In order to ensure that railroad vehicles operate with as little wear as possible on material, locomotive manufacturers seek solutions to recognize rolling early and prevent it. Rolling reduces the fatigue limit of the wheelset. Especially when it comes to new locomotives, systems must therefore be developed to recognize and reduce rolling. Railroad vehicle manufacturers are paying particular attention to safety and durability of both the locomotive as well as its components – for example, proof of the fatigue limit for wheelsets. The compact measurement system is installed on-board the locomotive.

Together with experts from DNV-GL Maritime Advisory, imc developed a Torsional Vibration Limiting System (TVLS). It excels through its flexibility, performance and availability.
Test measurements have shown that damage is brought about not by high levels and individual events, but instead by many small events. Figure 2 illustrates that a system for preventing rolling contributes to a manifold reduction in torsional vibration.

The torsional vibration limiting system (TVLS) offers the following advantages:
Working together with its partner DNV-GL Mar-itime Advisory, imc offers a comprehensive solution for railroad vehicle manufacturers. This consists of the measurement system and the application for recognizing rolling, which integrates the algorithm developed by DNV-GL Maritime Advisory. This is fine-tuned to the type of locomotive.