STATIC SCREENS
PURPOSE
Static screens are flat, rectangular screens with a mesh aperture of a few millimeters. They are used to arrest small quantities of small debris and are generally used as a safeguard rather than a pro-active system.
They are found at the outlet of cooling towers, behind thru-flow travelling screens or whenever an ultimate assurance that no debris larger than the aperture of the main screen are found in the water, is required.
DESCRIPTION
The mesh is secured on the panel frame that is slid into the grouted metal wall guides. The water flows across the mesh and the debris are arrested. The screen is lifted out and cleaned when the water flow is interrupted.
Installing a second panel in series with the first one makes it possible to lift the panel out for cleaning without interrupting the flow or the screening. Such filters are not to be used with high debris-loading or to cope with high levels of head-loss. Under a certain level of head-loss and depending on the machine size, it is impossible to lift and remove the device.
They have lift trays to collect the debris as it falls off during lifting out.
ADVANTAGES
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Simple and efficient
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Economical (low CAPEX)
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Easy to install
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No moving part
SIZES AND DATA
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Widths: up to 5 m
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Heights: no limit, uses superimposed elements
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Mesh aperture: 3x3 to 10x10 mm
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Maximum lifting head-loss
Without rollers: 5 cm (2”)
With side rollers: 25 cm (10”) -
Structural head-loss: 1.5 m H2O (5 ft)
OPTIONAL FEATURES
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Side rollers for lifting without cutting the water flow
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Lift beam
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Deck storage rack
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Lift chain
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Lifting structure and hoist at deck level
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Differential level measuring system
MATERIALS
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Panel frame: painted carbon steel for fresh-water applications, stainless steel for seawater applications
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Wall guides: AISI 304L for fresh-water applications, AISI 316L or duplex stainless steel for seawater applications
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Mesh: in all cases, stainless steel or composite materials
