The HSM – the new generation of milling machines
The HSM was designed as a high performance rail milling machine for preventive treatment with a high metre output (> 2000 m) per hour. However, the actual demand is focused on high and very high material removal, a very high machining volume per hour. Here to, the HSM has an output which is at least double that on conventional rail milling machines.
The HSM (High-Speed Milling machine), a milling machine of the next generation, is the result of our proven collaboration with our long-term partners Mevert Maschinenbau GmbH, Lauenhagen (work engineering) and Gleisbaumechanik Brandenburg / H. GmbH, Kirchmöser (vehicle engineering). The HSM has been approved by the German Railway Authority EBA and in April 2016 obtained its clearance by DB Netz AG.
Description of the machine
The HSM is a self-propelled three-piece trainset in conventional design. It is suitable for milling both on various mainline networks and in metro networks. The measurement (longitudinal and transverse profile) and testing (eddy current) equipment of the machine has been approved by DB.
Mode of operation
Milling is performed as down-cut milling. The chips are sucked off at the milling tool. The milling units ensure an extremely flat pressure angle of the milling cutters at the rail and thus minimize the residual defect compared with conventional milling modules. The transverse and longitudinal profiles of the rail head are created according to EN 13231-3:2012. Apart from the engine, the large diameter of the milling cutter and the arrangement of the milling plates contribute to achieving working speeds of more than 2,500 m/h. The milling process is free of sparks and dust. The cutters are arranged so as not to interfere with the clearance gauge. The replacement of the milling cutters is made by blocks inside the machine.
Scope of application and performance
The HSM can be used for maintenance and repair as well as for preventive rail treatment. The latter is a novelty in mobile rail treatment. Both high working speeds and low metal removal of only 0.2 to 0.3 mm per milling unit are possible. This way, defects due to rolling contact fatigue, such as head checks and squats, are safely eliminated already in their initial stages. As a consequence of the longitudinal grooves produced, the treatment with the HSM also results in lower noise emissions. So far, outputs of 700 m/h at a metal removal of 5.0 mm on the upper face of the rail (maintenance and repair runs) and of 2,550 m/h at a metal removal of 0.4 to 0.6 mm (preventive treatment runs) have been achieved.