Clearing drains and cleaning ballast following tracklaying on Norway’s Gardermobanen is the latest task to be completed by the innovative vacuum excavator developed by Disab.
With only two operators, Railvac 16000 can move along the line to its required position and within 2min be ready to work. Because Railvac uses powerful air suction rather than excavation with a metal grab, ditches can be dug with less waste and spoil, and ballast can be cleaned quickly in situ. On the Gardermobanen, drainage channels were cleared of construction dust and spoil by simply sucking it out at each end.
Nearly 60% of Railvac applications so far have involved cable work. Excavation of cables during track renewal work using suction is much less damaging to the cables, and in six years only one minor cable damage incident has occurred. Up to 200m3 of material can be excavated in 8 hours.
To clean ballast, the Railvac nozzle is buried in the ballast and moved around on its flexible hose. Depending on the suction setting, only dirt, litter and small stones are removed, leaving the ballast itself in place. Railvac can also act as a tamper with the nozzle directed under the rail by one person; this is especially effective on bridges.
Disab has sold six machines at a cost of US$1m each. Three are at work in Sweden, one in Norway, one in Slovakia and one on Hong Kong’s Mass Transit Railway.
Disab Vacuum Technology AB
Reader Enquiry Number 140
