Tower excavator

TOWER EXCAVATOR, cable excavator (EN: tower shovel; DE: Turmbagger; FR: dragline à tours; ES: excavadora de torre; RU: башенный экскаватор) is the single-bucket installation for the excavation and transportation of the useful minerals and overburden rocks along the direction, which is perpendicular to its movement. It comprises two towers, namely, the machine-containing one and the supporting one (contra-tower), between which there are stretched two parallel (at the distance of 2.5-3 metres) carrying ropes (Figure).

The scheme of the tower excavator:The scheme of the tower excavator

  • 1, 2 - the machine-containing and supporting towers;
  • 3, 6, 8 - respectively, the carrying, unloading, and traction ropes;
  • 4 - the carriage;
  • 5 - the bucket of the valve type;
  • 7 - the balancer;
  • 9, 13 - respectively, the rock and coal bunkers;
  • 10 - the dumping conveyor;
  • 11, 14 - respectively, the polyspast and the winch for the lowering of the balancer;
  • 12 - the drive of the traction winch;
  • 15 - the mine cart;
  • 16 - the tracked chassis device.

There moves on the ropes the carriage with the bucket of the valve, skip, or grapple type, which is suspended under it. Both towers move independently, parallel or along the curved trajectories on the tracked or rail chassis. The bucket of the tower excavator is lowered onto the stope by the system of the carrying ropes with the balancer. The volume capacity of the bucket of the tower excavator is 8-10 cubic metres for the rock and 12-15 cubic metres for the coal; the distance between the towers is up to 400 metres, with the depth of the development of up to 70 metres, the frequency of the working cycles is 20-30 per hour. The speed of the lifting of the bucket is up to 60 metres per minute, of the movement of the carriage (the riding speed) is 240-320 metres per minute, of the digging is up to 30-60 metres per minute, of the movement of the towers is 3-6 metres per minute.

The productivity of the tower excavator reaches 200 cubic metres per hour for the rock and 250 tonnes per hour for the coal. The tower excavator is used in case of the unfavourable configuration of the deposit, when the conducting of the transport communications into the open pit is difficult, in case of the development of the disturbed and intensely flooded (sometimes underwater) deposits, in case of the restoration of the dams, and so on.