Long line production

Production of standard sleepers using the Long Line process
The mould forms are located between two abutments anchored in the factory floor foundation. Tensioning wires (tendons) are threaded through the moulds and pretensioned against the two abutments. When the concrete has been cast, the moulds are covered with a tarpaulin. As with the Carousel method, the concrete cures in the moulds. As soon as the concrete has cured to the necessary strength, the sleepers are de-moulded before the pretension is transferred from the abutments to the sleepers.