The ROMAG Combined Sewer Overflow (CSO) Deflection Screen, fitted between the discharge culvert and the relief sewer, reliably retains all visible solids when the excess flows through.
ROMAG CSO screens are designed to a modular system. All types consist largely of elements which can be put together to obtain the most suitable type of screen for each particular application. The robust frame structure holds the screen grate, the cleaning carriage, the comb stacks and the hydraulic or pneumatic cylinder.
The screen grate is built from pre-tensioned narrow screen bars. The small bar cross-section ensures optimum use of the screen area, low screen resistance and high flow capacity. The standardized bar interval is 4mm, so that all the undesirable floating materials are retained.
One or more cleaning carriages are arranged on the outflow side, depending upon the screen length. They travel in guides over the screen surface. The comb stack, which is mounted on the cleaning carriage, engages in the screen grate and supports and guides the screen grate bars. The comb stack accordingly replaces the transverse stiffener elements which are undesirable in water cleaning systems. The screen cleaning is switched on and off as a function of the level. The drive is typically hydraulic and designed for extreme duty.
The ROMAG CSO screen is typified by its robust structure. When screened material becomes clogged, the fault is cleared by repeating the operation. A special changeover valve on the drive unit controls the movement of the cleaning carriage. No fault-prone limit switches are needed. The hydraulic drive unit can be installed outside the screen area. Only two hydraulic lines lead into the wet chamber. Continuous cleaning occurs during operation. No cross-bracing is required in the screen area. The screened material is diverted and scraped off at the end positions. Controlled transport of screened material can be affected to a predefined location. Emergency overflow is provided.
The ROMAG CSO-screen requires low maintenance. After the storm, the screen is so clean that subsequent manual cleaning is superfluous. A monthly functional check or verification after exceptional rainfall will be sufficient.