The Copa® Mechanical Raked Bar Screen is suitable for almost all CSO applications. The Mechanical Raked Bar screens modular design makes it easy to retrofit, through 600mm diameter manholes, into existing overflow chambers.
• This screen incorporates a David Froud Invention
• 4,6,8,10 and 12 mm bar spacings
• Continuously mechanically raked
• Can retrofit through 600mm dia manhole
• Stainless steel
• Retains screenings in the flow
• Hydraulic Drive
Applications
The Mechanical Raked Bar Screen applications include storm tank discharges, emergency overflows on pumping stations, storm weirs on a sewage treatment works and overflows within the sewerage system. The screen is ideal for both retro-fit and new Storm overflow chambers.
Operating Principle
The Copa® Mechanical Raked Bar Screen allows water to pass through to overflow whilst retaining the screenings in the flow. The screen is continually raked by an hydraulically driven cleaning mechanism. Flow rates from 50 -2400l/s can be catered for with a single screen module, although multiple units may be used to increase flow capacity.
With over 250 screen installations ranging from 50 l/s to in excess of 20,000 l/s the Copa Mechanical Raked Bar Screen has a proven track record for efficient, reliable and cost-effective sewer overflow screening.
Operation
Eimco Water Technologies, following extensive testing into vertical CSO screens concluded that they are far less efficient than screens which are installed horizontally. The Copa Mechanical Raked Bar Screen utilises fixed stainless steel bars which can be retrofitted through a 600mm diameter manhole.
The bars are continually raked by an hydraulically driven cleaning mechanism. Water is allowed to pass through to overflow whilst screenings are retained in the continuation flow.
Research Lays Vertical Screen to Rest
Use of the horizontally configured screens ensures that all flows, whether high or low, are screened with velocities kept to a minimum. The entire flow is in contact with the screen whilst the perpendicular flow path screens more efficiently.
Because the bars of the horizontal screen are actually oriented vertically, they are far stronger than horizontal bars which tend to sag, especially on longer screens and the vertical bars can be walked on for more convenient access to the installation.
Maintenance
The normal maintenance of the Mechanical Raked Bar Screen, is to inspect the screen periodically to ensure the surface area of the screen is free from any obstruction. It is also recommended that a dry run test is carried out. Both procedures are easy to carry out.
All maintenance may be carried out from the top/clean water side of the screen with the guide rods, combs, drive unit being easily removed for replacement/inspection. The main framework and screening bars should not be required to be removed, however should this be necessary, each module may be split from its partners and removed, should this be a slave unit from the end of the screen assembly then it is possible to re-establish the operation of the screen without this module at a reduced flow capacity.
Other maintenance required is replacing the hydraulic fluid within the hydraulic pump which may be carried out at its location within the control kiosk. These oil changes/checks should be carried out on an annual basis.
Advantages
• 4,6,8,10 and 12 mm bar spacings
• Continuously mechanically raked
• Can retrofit through 600mm dia manhole
• Stainless steel
• Retains screenings in the flow
• Hydraulic Drive