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AssigneeFoseco International Limited
InventorsFriedhelm Demey, Renate Jahre, Hans Riethmann, Mario Arruda, Antonio Cassara, Raphael Neto, Fabio De Oliveira, Sueli Pereira, Kazuhiro Nakano
Estimating the term…
Method for the production of a closed edge refractory foam filter, by providing a reticulated foam substrate having at least one first surface for forming a side face of the filter and two opposed second surfaces for forming the through-flow faces of the filter, applying a liquid including an organic coating component to the first surface, solidifying the organic coating component to form a filter precursor having a continuous volatilizable coating on the first surface, and impregnating the filter precursor with a slurry containing particles of a refractory material, a binder and a liquid carrier. The impregnated filter precursor is dried and fired to form the filter having a closed edge.
A method for the production of a closed edge refractory foam filter, comprising:—
Dependencies are inferred from the claim text.
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From the US filing history. Foreign family members aren’t listed.
Refining by liquating, filtering, centrifuging, distilling, or supersonic wave action including acoustic waves: by filtering
Other inorganic materials, e.g. ceramics: ceramic foam
Based on carbon, e.g. graphite: obtained from polymer precursors, e.g. glass-like carbon material
Based on carbides or oxycarbides: based on silicon carbide
About 4 years 3 months of term left · ends 11 Feb 2031 (estimated)
This application is the U.S. national phase of International Application No. PCT/GB2010/000503 filed 19 Mar. 2010 which designated the U.S., the entire contents of which is hereby incorporated by reference.
The present invention relates to a method for the production of filters suitable for filtering molten metal and to filters made by such a method.
Molten metals usually contain solids such as oxides of the metal and other impurities which may cause the final cast product to have undesirable characteristics. Filters have been devised to remove these impurities from the molten metal during the casting process. Normally these filters are made of refractory materials to withstand the high temperatures associated with molten metals.
Embodiments of the invention will now be described by way of example only with reference to the accompanying drawings in which:—
FIG. 1 is a schematic diagram of a cross-section of part of a filter in accordance with an embodiment of the invention;
FIG. 2a is a cross-section of a conventional filter obtained using CT X-ray imaging and FIG. 2b is a negative of the same image.
FIG. 1 is a highly schematic cross-section of part of a filter 10 in accordance with the present invention. The filter 10 has a closed peripheral edge 12 and comprises an irregular network of strands 14 surrounding and defining pores/voids 15. Both the closed edge 12 and the strands 14 are slurry formed from a refractory material. The strands 14 have cavities 16 due to the reticulated foam burned out (volatilising) during firing of the filter precursor. Cavities would also be present in the closed edge 12 where the volatilisable coating was previously present. These would be located along the dotted line.
A node may be defined in the filter where two or more strands 14 meet. Some of the nodes in the filter have been labelled A. The thinnest part of the closed edge 12 is at the midpoint between two surface nodes. Examples of the midpoint have been labelled B. It can be seen that the thinnest point of the closed edge 12 is of comparable thickness to the strands 14.
Methodology