Moving ahead with the right rail car positioner
To move the wagons into and out of the car dumper platform, a rail car positioner (aka side-arm charger) can be installed alongside the rail track.
Three types of positioners to suit your needs
Classified by traction mechanism:
- Rack & pinion positioner: Incorporates cartridge drives with pinions fix-mounted on a travelling positioner frame and machined racks mounted on a secure longitudinal foundation between the positioner rails to drive the unit along the rails.
- Rope-drawn positioner: Driven by a winch and incorporating sheaves and wire ropes.
Classified by type of travel drive:
- Positioner with electro-mechanical drives: Incorporates a travel drive mechanism consisting of an electric motor and gearbox assembly controlled by a variable frequency drive.
- Positioner with hydraulic drives: Incorporates a travel drive mechanism consisting of a power pack and hydraulic motors, which also enable precise positioning of the positioner.
Classified by application:
- Positioner for C-type car dumpers and side-discharge tipplers: Can move either a whole train or only a group of wagons and has one longer side arm with a wagon-compatible coupling at the end.
- Positioner for O-type car dumper: Moves the whole train each time with no need to uncouple the wagons and has one or two side arms with no need for a special coupling at the end.
How the rail car positioner operates
When the wheel grippers holding the railcars are released, the positioner pulls a rake of full cars close to the entrance of the car dumper platform. The second railcar is uncoupled from the full rake, which is held in position by the wheel grippers. The positioner then pulls the first two cars onto the car dumper platform, uncouples itself from the two cars, and moves out of the car dumper platform. The side arm of the positioner lifts to allow the positioner to travel past the car dumper back to the entrance of the car dumper platform. The positioner then waits for the next two cars to be unloaded, pulls in the next two loaded cars onto the platform, and in the process pushes the empty cars out of the car dumper platform.