The first of two High-Output Ballast Cleaning Systems being supplied by Plasser & Theurer to UK infrastructure company Network Rail is due to enter service this month, with the second to be delivered in the summer of 2005. Both machines will be operated by First Swietelsky under a two-year contract that also covers other high-output track renewal plant (RG 9.04 p522).

At the heart of the HOBC is an RM 900 RT ballast cleaner which can also lay a geotextile mat under the track and add new ballast to recovered material. It is supported by 36 MFS-D conveyor/hopper units and eight MFS-SB units with slewing conveyor belts for unloading spent ballast. The self-propelled HOBC has two power cars and is designed to clean up to 900m3 of ballast per hour, equivalent to 400m of track.

Plasser & Theurer began trials of the RM 900 RT with five MFS units and a power car in May last year at Weissenbach. Many approval tests were also undertaken in Austria before the first HOBC unit was delivered via the Channel Tunnel, with extensive trials in the UK starting in August 2004. n