Abstract: A filter screen structure for a backflushed liquid filter has a screen separating the raw-liquid side of the filter from the clean-liquid side thereof, including at least one row of substantially parallel rods extending along the screen, wherein the screen is threaded between the rods, partially enveloping the rods alternatingly from the raw-liquid side of the filter and from the clean-liquid side thereof. At least some of the rods are provided with substantially circumferential groove-like recesses, facilitating the passage of the liquid from the raw-liquid side via the screen to the clean-liquid side.

Abstract: A filter element and a system for cleaning the filter element, including a plurality of layers of fibers arranged in substantially uniform orientation over at least a portion of their active length, along which portion at least, each of the fibers is disposed in close proximity to its adjacent fibers, and a body member constituting a backing surface for the fibers. The system further includes nozzle means for applying at least one fluid jet against the fibers; and means for applying a relative movement between the fiber layers and the fluid jet.

Abstract: A self-cleaning filter including a filter housing having at least a raw-liquid inlet and a clean-liquid outlet, a filter medium interposed between the raw-liquid inlet and the clean-liquid outlet At least one nozzle is located in proximity to the filter medium and is connectable to at least two different sources of pressure, one of which pressures is higher than the pressure prevailing in the filter, the other one being lower than the pressure prevailing in the filter There is also provided an arrangement to produce a relative movement between the filter medium and the at least one nozzle to the effect of having a substantial part of the surface area of the filter medium covered by the nozzle.

Abstract: A method for filtering a fluid in a filter system, including a filter housing and a filter element, which method comprises modifying filter throughput in such a way that differential pressure across the filter system caused by build-up of filter cake is substantially maintained at a predeterminable level for at least part of filter-operation time between flushings. A filter system for a fluid for operation by the method is also described.

Abstract: There is provided a filter element for filtering fluids. The element consists of a body member having at least two openings provided, respectively, access and egress for the fluid and a plurality of fibers of a substantially uniform orientation over at least a portion of their active lengths along which portion at least each of the fibers is disposed in close proximity to its adjacent fibers. The invention also provides a flushable filter device incorporating the above described element.

Abstract: There is provided a method for cleaning corrugated filter elements by means of suction nozzles. The method comprises a corrugated filter element and at least one suction nozzle movable relative to the surface of the element. The specific parameters of the method are interrelated in accordance with a specially developed given formula.

Abstract: There is provided a fluid filter system cleanable by suction. The system comprises a filter element fixedly attached to a substantially rigid filter-element support mounted in a filter housing and provided with a plurality of openings, at least one suction nozzle having an inlet opening located in close proximity to the filter element and adapted to move with its inlet opening past the filter element in such a way as to cover, in succession, at least some zones of the filter element while producing a suction flow. The invention further comprises guide means for guiding a fluid stream from the high-pressure raw-fluid space of the filter housing to a low-pressure zone created by the suction nozzle between the inlet opening thereof and that portion of the filter-element support which faces the suction nozzle.

Abstract: There is provided a filter element for filtering fluids. The element consists of a body member having at least two openings provided, respectively, access and egress for the fluid and a plurality of fibers of a substantially uniform orientation over at least a portion of their active lengths along which portion at least each of the fibers is disposed in close proximity to its adjacent fibers. The invention also provides a flushable filter device incorporating the above described element.

Abstract: A method for effecting the cleaning of a clogged fluid filtering member in a filtering system situated between an inlet and an outlet port comprising utilizing at least a portion of the fluid to be filtered in said system to impart motion to a movable hollow cleaning body provided therein in fluid communication with a valved cleaning outlet and to carry matter unable to pass through said filtering member into a fluid intake portion of said cleaning body and out said cleaning outlet.