| 摘要 |
Individual sleepers or groups of sleepers are replaced by sucking up the ballast around the sleepers, pulling out the old sleepers and putting in the new sleepers which are kept raised while they are secured to the rails. The ballast is sucked up into a rail-mounted wagon (16) and can later be discharged from the wagon to be used as ballast for the new sleepers. A rail-mounted excavator (22) with a grip device is used to introduce the new sleepers beneath the rails. |
