Bar screens are designed to retain coarse materials from the flow stream; they are made of uniformly separated flat bars of stainless steel.
Bar screens are tailored to the specific channel dimensions, and are designed to be mechanically cleaned. For this purpose, a TARNOS trolley GRAB type trash rake, common for the whole installation, can be designed to clean all bar screens in sequence and discharge the debris a the end of the line.
The machine is composed by the following components:
- A wheeled carriage, which holds the trash rake in its interior and is designed to transverse on the monorail.
- A claw trash rake, designed to be lifted down to the botton of each bar screen to clean it and remove the debris.
- Monorail beams, designed to support the monorail track
- Overhead track, double I-beam monorail type
The claw rake is suspended by two strong cables that allow the vertical movement. All the assembly is installed inside a carriage structure that can traverse horizontally on overhead rails (crane type). Most typical design is to have one monorail for this movement, but our system has two monorails for better stability & longer durability.
The traversing movement is done by two trolley motors that work at the same time to ensure a smooth movement in both directions.
When the rake is above a cleaning station (bar screen), the limit switches stop the traversing movement, and the grab hoists down to clean the screen.
Rollers on the rake ensure a smooth contact between the rake and the bar screen. There isn’t metallic contact between the bar screens and the rake, increasing the lifetime of the components and an optimal penetration.