The constant increase of traffic and transit speed in railway lines, associated with the new safety standards, require more frequent and more attentive monitoring of the risk factors.The train wheels and their interaction with the rail together with the pantograph carbon stripes and their interaction with the overhead line represent a key factor of this risk so that their parameters must be measured with good accuracy and high frequency.At the same time the use of wayside monitoring systems permits not only to reduce the risk of derailments (important safety impact) or overhead line damages but also to contribute to reduce the cost and keep under control the maintenance of the vehicle and the maintenance of railway infrastructure.
Until recent time, manual measurement methods required trains to go to the workshop for checking, bringing along undesirable downtime; with new generation of automatic measuring systems, the trains need just to pass through the measuring site, without any negative effect on their operational schedule.
Integrating Automatic measurement system with Automatic Vehicle Identification System allows the correlation of measures over time and the analysis of wear trends: this is key to paving the way for predictive maintenance at the expense of the less effective and more costly traditional preventive maintenance.
Automatic systems are mainly located in a depot yard, where trains pass at low speed, to allow for measurements before and after maintenance operations.A parallel approach that has been gaining traction in the last years is to inspect trains on regular lines, and to adopt technologies for automatic train identification, in order to keep track of trains and the wear conditions of their pantographs and wheels. The ideal scenario is to place these Automatic Train Inspection Station (ATIS) along the busiest lines, forming the Automatic Train Inspection Network (ATIN), used to inspect the highest possible amount of trains, which are very often high speed traffic lines.
The evolution of the automatic measurement technology therefore aims to obtain stable accurate and reliable measurement at ever-increasing speed distributed on different ATIS spread all over the railway network forming an ATIN. In this field Mermec has developed his experience that culminates in a cutting-edge system capable of measuring wheels parameters at the speed of 250 km/h and pantograph parameters at the speed of 320 km/h.