Automatic hydraulic device for cleaning the grilles of the entrance building

PROJECT NAME: Automatic hydraulic device for cleaning the grilles of the entrance building


INVESTOR: Hrvatske vode, Hidrotehnički objekti Ltd.


LOCATION: PS Vedrine, Trilj





  • duration of one cleaning cycle in continuous and automatic operation: 12,5 min
  • transport vehicle speed: 8,6 m/min
  • transport vehicle length: 8 m
  • total installed power: 8,4 kW
  • operating voltage: 400 V / 50 Hz
  • control voltage: 24 V DC
  • hydraulic unit operating pressure: 130 bar
  • conveyor belt speed: 0,8 m/s
  • grid dimensions: 7,13 x 10,8 m



In order to prevent the introduction of alluvium into the water intake area in the pumping station and to block the operation of the pumps, immediately in front of the pumping station, a grate for the accumulation of alluvium is installed at the entrance. Debris that reaches the grille is removed with a self-propelled hydraulic cleaner with a telescopic "T" arm consisting of one fixed and two movable segments. After the telescopic "T" arm removes the debris from the grate, it is deposited on a conveyor belt for transporting the debris to the collection pit with a descending ramp, which is periodically cleaned, and the debris is transported to the landfill. The cleaner can operate in three operating modes:


  1. manual operation - the operation of the scrubber is controlled by the operator directly using a remote radio control or via a manual control unit with cable, where the operator manually turns the drives on and off, and after the operation the transport vehicle and telescopic arm must be brought to the starting position,
  2. continuous operation - is provided as the basic mode of operation of the cleaner, where the start of the cleaner is done manually by giving a command on the control panel, and the operation of the cleaner takes place automatically,
  3. automatic operation - is switched on by switching the selector switch to the automatic operation position, and in order for the cleaner to work, the water level meters in front of and behind the grate must detect an impermissible difference in the water level. When the difference is found on the measuring devices, the work cycle begins by first activating the conveyor, and then the telescopic arm in the first working position, which is raised to the upper position, then ejected to the end position and begins to lower the rake to the bottom of the watercourse. When the rakes reach the lowest position, they move closer to the surface of the grid, after which the process of cleaning the grid begins by raising the telescopic arm. When the telescopic arm reaches the upper position, it is moved towards the conveyor in order to shake the collected debris into the trough. After that, the transport vehicle is started, which moves the scrubber and sets it to the next working position, and the grid cleaning procedure is repeated. The entire grille is cleaned in four passes, ie in four working positions.


The working movements of the telescopic arm are realized by the hydraulic drive, which consists of an electro-hydraulic unit, an additional oil tank and a hydraulic pipeline. The belt conveyor for shipment of alluvium is driven by electric current via an electric motor.


The cleaner system is equipped with safety switches and sensors that control the correct operation of the cleaner.