The main goal of railroad operators and rolling stock owners is to keep the trains running without interruptions in a safe and secure manner. Maintenance of rolling stock plays a vital role in this goal, and both owners and operators routinely perform corrective, preventive, and predictive actions to ensure that freight wagons circulate smoothly and securely throughout the rail network.
Organizations such as VPI European Rail Service GMBH (VERS) evaluate non-destructive testing methods and processes and develop maintenance guides and norms to ensure that European freight wagons comply with the latest safety and operational requirements. VPI also carries out technical assessments of maintenance workshops to ensure compliance and to qualify them based on the VPI European Maintenance Guide (VPI-EMG). VPI certification ensures that maintenance operations are conducted with the best and most modern tools and procedures with unified rules and testing criteria.
One of the key requirements set by VPI is that rail wheels are kept within certain levels of residual stress levels. The braking process used on railroad cars creates tensile stresses in the circumferential direction due to the thermal expansion and subsequent cooling of the wheel rim. Excessive levels of residual stress can lead to the generation of internal and external cracks and catastrophic failure of the wheel while in service.
With over 150,000 vehicles in commercial service worldwide, Alstom is one of Europe’s largest suppliers of high-speed trains, metros, monorails, and trams. In addition to manufacturing and commercializing equipment, Alstom also provides infrastructure, signaling, digital mobility solutions, and maintenance services of rolling stock.
In order to increase the added value of the services and grow its customer base, Alstom´s main maintenance workshop in the Netherlands was interested in obtaining certification from VPI to perform IS1-level maintenance activities for rail operators, which requires performing measurements of stress levels on railroad wheels.
In order to meet the requirements set by VPI, Alstom acquired Innerspec’s portable residual stress measurement system which was delivered together with a complete onsite training session at Alstom´s site near Rotterdam. After the training, Mr Hans Heemskerk, Business Optimalisation Manager at Alstom said:
“Alstom is very happy to be the first VPI certified company in Europe that can carry out full IS1 treatment on wheelsets while mounted on wagons with support from Innerspec’s residual stress measurement technology. This equipment will help Alstom provide new maintenance services in a fast and cost-efficient manner to our customers”.
Continuing with a long tradition of industry firsts, Innerspec introduced the first hand-held EMAT system for measurement of residual stress in railroad wheels in 2015, and after achieving accreditation by VPI, it has supplied nearly 100 systems for maintenance workshops and rolling stock owners around the world. The EMAT technique and equipment developed by Innerspec are also being evaluated for the measurement of residual stress in other metallic components such as gears, pipes, plates, and steel bridges by companies and research institutes.
If you would like to know more about Innerspec´s residual stress measurement technology or to schedule an onsite or virtual demonstration, please contact us at sales@innerspec.com.
Handheld Solution for Measurement of Residual Stresses on Railway Wheels using EMATs
Residual Stress Measurement Solution from Innerpec