AUSTRIA: The capital’s transport operator Wiener Linien is testing an Automatic Track Machine Oscillator tramway rail grinder, which was developed by Plasser & Theurer in collaboration with industry partners, university academics and infrastructure operators as part of the Shift2Rail research programme.
ATMO is the result of a market study by Technische Universität Wien, with Plasser & Theurer responsible for design and manufacture.
It is designed for grinding plain track and turnouts on tramways, where small curve radii can cause the grinding stone to leave its ideal line of movement and some sections of line require more intensive treatment than can be performed in a single pass. According to Plasser & Theurer, oscillating grinding is especially recommended for areas prone to developing rail defects, such as at stops.
The ATMO trailer is hauled to the worksite by a power car or road-rail vehicle, and controlled from the traction unit without needing staff on the grinder.
It combines conventional whetstone grinding with oscillating grinding. There are two grinding saddles each featuring two grinding stones per rail head, with the 100 kW water-cooled sound-insulated diesel engine with exhaust after-treatment providing power for the hydraulic mechanism which moves the grinding saddles horizontally in the longitudinal direction of the rails at up to 8 km/h with variable frequency.
It can grind at speeds of up to 30 km/h to enable operation alongside regular traffic without needing line closures. The four-axle trailer can travel on curves as tight as 16·25 m and work on curves down to 17·25 m in radius, with the grinding stones aligned so that they are always positioned above the rail head. Unlike with conventional grinding vehicles, there is no need to lift the grinding stones when passing over turnouts and crossings.
The machine is equipped with a 2 800 litre water tank for wet grinding to improve output and prevent sparks.