Shadowing from the screen

The wave nature of many combined sewer overflow (CSO) screens means that they are problematic to clean. As the diagram here shows, the angle of incidence the cleaning jet makes can be vitally important. If the angle is too shallow, then the screen itself will block the cleaning jet and prevent good cleaning.

To overcome this, we try to design cleaning systems so that as much as possible of the screen below sits within a 60° cone of the cleaning head. This means that the surfaces within this cone will be hit by jets that are no more than a 30° angle from the horizontal.

Keeping the cleaning head as high as possible above the screen increases the radius of the cleaning area and so means fewer cleaning heads need to be used. In many situations there is a practical limit on how far above the screen the ScreenBlaster Machines can be deployed

Another design consideration with screens that require multiple cleaning is the orientation of the screen wave in relation to the cleaning heads. If the crest of the waves runs parallel to the layout of the ScreenBlaster system, then a more effective clean can be achieved as there is less blocking of the cleaning jets by the wave screen itself. In contrast, if the wave form is perpendicular to the lay out of the cleaning heads then more of the jets will be blocked by the wave.