Cable Operated Bar Screens HKI and TGS are robust equipment designed for heavy duty applications. They are specially designed for deep and wide channels for installation in pumping stations or inlet structures of high capacity water and wastewater treatment plants. With vertical installation possibility they require less space for screening. Cable Operated Bar Screens consist of a two main part: Parts in the channel; which are bar screen, guide frame and dead plate are equipped with parts over the channel; which are chassis, discharge chute, raking and cleaning mechanism. The upper part can be both designed as stationary (HKI) or travelling (TGS) versions. 

Operation Principle for Stationary Cable Operated Bar Screen (HKI):

In this design the upper part is connected to the lower part. The equipment waits in park position until it receives a signal from one of the channels that the pre-set differential water level is reached and it means that the screen has to be cleaned. The bar screens are cleaned by the help of a grab rake. The grab rake is lowered down to the bottom of the channel in open position and closed to carry the collected debris while going up. The collected debris is cleaned by a counter wiper when the ladle rake reaches to discharge point. Here the screenings are either removed to a container or a transporter for further processing.

Operation Principle for Travelling Grab Screen (TGS):

The operation principle is the same with “HKI” but the only difference is the upper part is travelling on a trolley. Thanks to its special control program, the Travelling Grab Screen “TGS” has the information of its actual position. By the help of special IP identification; the location of the channel from which the signal received is defined and the trolley starts to move towards that direction. The trolley is stopped at exact place by the help of the encoder motor as well as electro-mechanical positioners located on the trolley.
As soon as the trolley stops, the grab is lowered in the channel in open position. When it reaches the bottom it is closed and lifted up all the debris collected on the screen bars. The solid matter in the grab is removed by the wiper as the grab reaches to the discharge point. Here the screenings are either removed to a container or a transporter for further processing.

Generally one cycle is sufficient to clean the entire surface of the clogged screen and decrease the differential water level to pre-set value but if not one more cycle is automatically started. After completion of relevant cycle equipment stays in park position; the grab is up and in open position ready for service, and waits for an upcoming signal from any of the channels.


Bar spacing: 8 ÷ 100 mm
Channel width: 800 ÷ 4000 mm
Discharge height: up to 30 m
Installation Angle: 75° ÷ 90°
Material: Carbon steel with surface protection or Stainless Steel



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