Process for casting a part from a pour of molten metal into a mold assembly
View Patent ↗This invention relates to filters made from a refractory material, preferably an insulating material, and chemical binder. The filters are used in the foundry industry to filter molten metal. The invention also relates to a process for preparing the filters.
1. A process for casting a part from a pour of molten metal into a mold assembly, comprising the steps of:
inserting, in a flow path of the molten metal into the mold assembly, a foundry shape having openings through which the molten metal flows and having a surface that traps and removes contaminants therefrom, the foundry shape comprising a refractory material that comprises at least 50 weight percent of hollow insulating aluminosilicate microspheres having an average diameter of about 10 microns to 350 microns, based upon the weight of the refractory material, and an effective amount of a foundry binder selected from the group consisting of phenolic resin binders, phenolic urethane binders, furan binders, alkaline phenolic resole binders, epoxy-acrylic binders, and sodium silicate binders;
filtering the pour through the foundry shape;
allowing the metal to cool and solidify; and
separating the cast metal part from the mold assembly.
2. The process of claim 1 , wherein:
the openings in the foundry shape comprise an entrance means and exit means.
3. The process of claim 2 wherein the foundry shape is an integral part of the mold assembly or a pouring cup therefor.
4. The process of claim 2 wherein the exit means is concave.
5. The process of claim 2 wherein the exit means is convex.