Due to the mechanical contact between rail and wheel, high contact stresses lead to wheel damages like polygonisation of the wheels or wheel flats. The consequences are an increased derailment risk and increased sound and vibration emission. The proceeding damages lead to higher contact stresses and to an ever-growing and faster damage progress. As the damage progress increases exponentially, damage detection in an early state saves maintenance costs.

The Wheel Monitoring System (WMS) was developed by Müller-BBM for the automatic monitoring of wheels in rail-bound traffic systems. It will provide you with reliable information about any unroundness (polygonisation) of the wheels in your vehicle fleet and detects wheel flats. In former times, all wheels had to be checked regularly by putting the railway car out of operation and measuring the wheel condition manually in a time-consuming manner. Nowadays, the wheel monitoring system provides all necessary informations automatically. Maintenance is only necessary if wheel defects occur. You get detailed information about the damage progress and you are therefore able to plan the maintenance in advance. Maintenance costs decrease as you avoid regular inspections of the wheels.

The system consists of one or more test points that record the wheel data and a vehicle detector that identifies the railway cars. Ideally the measurement track is installed in the tram yard, enabling you to check the wheel condition easily during the passage of the trams when leaving or entering the tram yard. The data is transmitted to the data analysis unit. This PC evaluates the data with respect to parameters that describe the condition of the wheels. Unround or damaged wheels, even those with a small but progressing damage lead to increased damage parameters. The acoustical fingerprint of all railway cars is stored in a database. All users can access the wheel data and make a best use of them.

Major advantages are:

• Detailed knowledge and reliable data about the actual condition of your trains.
• The system can be integrated in the infrastructure of your company so that apart from the measurement point and the data analysis unit no additional hardware is required.
• The system is perfectly qualified for the rough environmental conditions it is used in.
• Quiet trams due to monitored wheels.
• A detailed documentation of the wheel condition supports you in case of claims for compensation.
• Maintenance that fits to the wheel condition is cheaper and more efficient.

The system will be integrated in the future Müller-BBM train monitoring system. This system will additionally use airborne sound for the monitoring of motors, fans and other aggregates during the vehicle pass-by in order to allow global condition monitoring for trains.