Abstract: An apparatus according to the invention includes filter sticks housed within a pressure vessel. Each filter stick includes a plurality of filter disks stacked about a fluid-pervious tube with a hollow core and retained about the tube by a retainer at each end. The filter sticks are disposed within a first compartment having fluid to be filtered with the hollow core of the tube in fluid communication with a second compartment for filtrate. A compression regulator, which is responsive to pressure within the compartment, is linked to at least one of the retainers so as to control relative movement between the retainers, which controls compression of the disks and interstitial space for fluid to flow therebetween. In use, automated compression control of the disks compensates for the effect of particle build-up in the filter, which would otherwise decrease the rate of flow through the filter.

Abstract: An apparatus according to the invention includes filter sticks housed within a pressure vessel. Each filter stick includes a plurality of filter disks stacked about a fluid-pervious tube with a hollow core and retained about the tube by a retainer at each end. The filter sticks are disposed within a first compartment having fluid to be filtered with the hollow core of the tube in fluid communication with a second compartment for filtrate. A compression regulator, which is responsive to pressure within the compartment, is linked to at least one of the retainers so as to control relative movement between the retainers, which controls compression of the disks and interstitial space for fluid to flow therebetween. In use, automated compression control of the disks compensates for the effect of particle build-up in the filter, which would otherwise decrease the rate of flow through the filter.

Abstract: The present invention is directed to a method of removing impurities from the effluent of an EDM process wherein the improvement comprises steps of: providing a filter apparatus; providing the effluent from an EDM process to said apparatus; filtering impurities from the effluent thereby forming a filtrate; removing said apparatus from said effluent; and back flushing said apparatus with said filtrate, said back flushing conducted at a pressure greater than atmospheric pressure, thereby removing the impurities from said apparatus.

Abstract: A flat annular disc filter paper has a plurality of randomly oriented fibers at its surface. The paper is impregnated with a phenolic resin so as to resist compression of the disc and swelling of the paper. The filter paper is made by soaking the paper in the resin, heating the paper and resin so as to burn and melt the resin into close contact with the paper and rolling the filter paper at a temperature above ambient temperature.

Abstract: The present invention is directed to a method of removing metallic hydroxide salts having impurities from an aqueous medium. The method includes the steps of:(a) providing an edge type filter;(b) passing an aqueous medium with metallic hydroxide salts having impurities to the filter;(c) removing the metallic hydroxide salts with the filter and forming a cleaned aqueous medium;(d) removing the cleaned aqueous medium from the filter;(e) drying the filter after the filter has become blocked by the metallic hydroxide salts and forming a powder; and(f) removing the powder from the filter, whereby the filter is unblocked.

Abstract: A flat annular disc filter paper has a plurality of randomly oriented fibers at its surface. The paper is impregnated with a phenolic resin so as to resist compression of the disc and swelling of the paper. The filter paper is made by soaking the paper in the resin, heating the paper and resin so as to burn and melt the resin into close contact with the paper and rolling the filter paper at a temperature above ambient temperature.

Abstract: A filter assembly is formed by arranging a large number of substantially annular, thin filter elements disposed around a radially pervious and hollow core so that a major portion of the core is surrounded by the filter elements. Slots between the filter elements allow passage of the liquid to be filtered. The filter assembly is enclosed in a closed vessel with the interior of the core being in communication with an outlet line. An initial axial pressure is established on the filter elements by a spring which acts on an end support engaging the end one of the filter elements. The axial pressure on the filter elements is controlled by controlling pressure in the closed vessel and thus the size of the slots is controlled to establish the desired filtering degree of the filter assembly.