Flex 600: A Modular Platform
Casram has developed the Flex 600, a new family of GRUs designed to adapt to different types of vehicles, including locomotives, high-speed trains, regional trains, passenger coaches, freight wagons, metros and trams.
The Flex 600 is not simply a product, but a configurable platform. The number of brushes, materials, flanges and construction features can be adapted to the specific application and the requirements of the train.
This modularity is complemented by a new service concept. Operators can choose between replacing the complete GRU or independently managing the main consumable components, particularly the brushes. Casram can also support customers through maintenance, refurbishment and inventory management programmes.
The Flex 600 has completed its qualification process and is now ready for market introduction.
From the GRU to the Smart GRU
The next step is the Smart GRU, or S-GRU.
The idea behind the innovation is simple: to use the GRU, which is already installed close to the wheel and axle, as a platform for collecting information about the behaviour of both the railway vehicle and the infrastructure.
By integrating sensors into the brushes or the GRU structure, it is possible to monitor parameters such as:
- vibration;
- temperature;
- acoustic signals;
- brush wear;
- position and movement;
- other indicators relevant to diagnostics.
The collected data are processed and transmitted to a digital platform, where they can be compared with the values that characterise the system’s normal operating conditions.
The objective is not merely to detect a failure after it has occurred, but to identify the early signs of an abnormal condition.
Predictive Safety
The S-GRU therefore introduces the concept of predictive safety.
An abnormal increase in temperature, persistent vibration or an acoustic signal outside the normal operating range may indicate the progressive deterioration of a wheel, axle, bearing or another component of the rolling stock.
By correlating information from multiple S-GRUs installed on the same train, it may also become possible to distinguish between a problem affecting the train and an anomaly in the infrastructure.
When several units positioned on the same side of the train detect the same event in succession, the system may identify a possible defect in the rail, a set of points or another part of the infrastructure. An anomaly detected by only one unit, on the other hand, is more likely to be associated with the vehicle itself.
This type of information can help operators to:
- intervene before a critical failure occurs;
- plan maintenance more effectively;
- reduce unplanned downtime;
- increase fleet availability;
- direct inspections more accurately;
- improve the overall safety of the railway system.
A Self-Powered Solution
Another important feature is the S-GRU’s independence from the vehicle.
The S-GRU is designed as a direct replacement for a conventional GRU, without requiring substantial modifications to the train. The energy required by the sensors, electronics and data transmission system can be generated by a small integrated alternator driven by the rotation of the wheel.
As a result, the S-GRU can operate without being connected to the onboard electrical systems. This feature is particularly relevant for freight wagons and vehicles where no dedicated power supply is available.
A Project Built on Complementary Expertise
The development of the Smart GRU requires collaboration across mechanical engineering, advanced materials, sensor technology, electronics and data analysis.
Casram works together with specialised partners:
- to develop and manufacture high-performance brushes and sensor-integrated solutions;
- to develop the electronics, signal management systems and data transmission architecture connecting the unit to the cloud;
- to analyse the signals and develop the methods required to distinguish normal operation from conditions that may indicate deterioration of the vehicle or infrastructure.
The Next Step
Casram is currently pursuing two objectives.
The first is to bring the Flex 600 family to market, as it is now mature and available for new railway applications.
The second is to identify a railway manufacturer or operator with whom to complete the development of the Smart GRU, collect data from vehicles under real operating conditions and precisely define the conditions that should trigger an alarm.
Turning a promising idea into an industrial solution requires field testing, reliable data and close cooperation with the organisations that design, manufacture and operate trains.
The GRU will continue to perform its fundamental current-return function. At the same time, however, it can become an intelligent observation point serving the safety of the railway system.
FRANCO PUFFI
CEO