VolkerRail Tamper DR75403
Photographed southbound approaching Grantham station while proceeding to its next job on 21 March 2011.
When in operation, this machine measures the line and level of the track, and either computing, or working to a design, lifts any slacks or dips out of the track, where necessary slewing the track from left to right if there are any errors in the line. The tamping banks have tines that vibrate at a certain frequency which when driven into the track settles the ballast under the sleepers. The tines also squeeze the ballast under the sleepers.
The far end of the unit has a Dynamic Track Stabiliser (DTS) that again vibrates the whole track unit to bed it in, and simulates high levels of traffic going over the line, meaning that the track can be put back into service with a higher line speed, also minimising the number of additional tamps needed after the work.
Picture added on 15 April 2011 at 19:27