Rolling stock

Modern rail vehicles are essential for reliable and efficient railway traffic. Together with the goods they carry, they are referred to as 'rolling stock'.

Fraunhofer Rail provides services throughout the whole product life cycle, from development and manufacture to the operation and maintenance of the rolling stock.

Development#

The services offered by Fraunhofer Rail in rail vehicle development include measures for ensuring reliability and long service life, manufacture which consumes a minimum of time, money and resources, the improvement of safety, ergonomics and comfort for users of the vehicles, and reductions in emissions of noise and pollutants into the environment.

As regards the licensing of safety-relevant software in the rail sector, Fraunhofer Rail gives advice on the development of distributed and modular architectures, their validation and certification, and the improvement of development processes and drawing-up of safety documentation in compliance with EN 50128.

With comprehensive numerical and experimental procedures relating to component sizing and methods of materials characterization and component inspection, the safe, reliable and cost-effective operation of rail vehicles is guaranteed. Against this backdrop, the developers at Fraunhofer Rail have come to specialize in safety components and structures exposed to stress, such as vehicle bodies, bearings, brakes, wheels and wheel-set axles, and complete wheel sets.

The efficient manufacture of products is ensured by the simulation and optimization of steps in manufacturing, by their being automated and made more flexible, and by quality inspection technologies.

Modern methods of sound analysis, methods for the investigation of hygiene, interior climate and seat comfort, and crash analysis procedures are designed to ensure that passengers are both safe and satisfied. Innovative procedures for sound design, the development of acoustic components and usability engineering (e.g. facilities with which passengers can adjust their own seating comfort) enhance the competitiveness of the products.

Manufacture#

Fraunhofer Rail develops physical methods for the non-destructive dimensional measurement and inspection of vehicle components and the characterization of materials, and transfers them to the application in which manufacturing processes are checked and monitored and manufactured components inspected for quality.

These solutions can be used anywhere where safety-related statements and quality certificates are called for. The methodological competence of Fraunhofer Rail comprises basic physical procedures, sensors, equipment engineering, handling techniques, techniques for the assessment and documentation of results, and the qualification and validation of new inspection procedures and devices.

The use of innovative inspection technologies involving ultrasound, eddy current, X-ray technology and thermography enable minute material defects to be detected.

As product quality is also a factor in competition, in-process measuring and inspection techniques are becoming more and more important in order to ensure 100% inspection and make it possible to regulate processes by means of early feedback. Machine vision processes are suitable for the inspection of geometric and surface quality parameters during manufacture. Non-contact optical sensors are particularly suitable for such applications on account of their high measurement speed. They also facilitate the integration of the human element in modern manufacturing processes by providing assistance and monitoring functions.

Operation#

To help prevent injury to humans and damage to the environment, the infrastructure, the rail vehicle and its load, and to help ensure undisrupted rail traffic flow, Fraunhofer Rail develops innovative technologies for the monitoring of rail vehicles and the goods they carry, and for fault diagnosis on vehicle components.

Both mobile (i.e. part of the vehicle itself) and static (i.e. positioned at selected overrun points) solutions are used.

For example, mobile solutions make it possible to carry out measurements during vehicle operation to ensure operational safety in various different running conditions and load constellations.

Static solutions monitor axle bearings for possible overheating and brakes for blocking on passenger and goods trains by means of non-contact infrared sensors. Optical measurement systems are integrated in the track bed and enable wheel profile wear to be monitored. Ultrasonic probes are integrated in the railhead and allow the tread to be inspected for damage while the train passes over the relevant section of track. Requirements involving increased safety, passenger comfort and operational reliability can thus be met. Profile scanners based on modern laser technology, for example – which have proved their worth in this application on many occasions – can detect loads which have slipped out of position or buffer overruns, and transmit warnings to the appropriate control centers. Spectroscopic measurements make it possible to detect excessive exhaust emissions, fires or leaks. They make an important contribution to the conservation of our environment and safety in rail traffic.

Maintenance and status monitoring#

Fraunhofer Rail develops solutions for the maintenance and status monitoring of rail vehicle components, and also of the machines and units used for those purposes.

Strain measurements, subsequent calculations of remaining useful service life and fracture mechanics investigations ensure that servicing and maintenance cycles can be fixed at a rhythm which will ensure optimum safety while also enabling costs to be saved and the useful service life of components to be extended.

Modern measurement and inspection procedures combined with analysis techniques make it possible to carry out status-oriented servicing and maintenance and determine the residual inventories of parts subject to wear and tear.

Wheel set measuring units check the wear status of the wheels in maintenance shops. In the case of block-braked wheels on freight cars, excessive residual tensile stress in the rim is detected by means of ultrasound. On this basis, maintenance levels can be determined reliably. After the reprofiling of wheel sets, inspection units ensure their compliance with geometric standards and freedom from cracks in components subjected to major strain. Here, optical measurement techniques and ultrasonic and eddy current inspection procedures are used.

Management systems combined with RFID technologies enable all servicing and maintenance work to be documented reliably throughout the whole life cycle of technical components.