# US 9,433,999 B2 · Manufacturing method of core and casting product using inorganic binder > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 9,433,999 B2 - Document ID: US9433999B2 - Status: Granted - Kind: B2 - Application number: 14/954,135 - Filed: 2015-11-30 - Published: 2016-07-21 - Granted: 2016-09-06 - Earliest claimed: 2015-01-20 - Assignees: Dr Axion Co., Ltd. - Applicants: Dr Axion Co., Ltd. - Inventors: Jeong Wook Park; Woo Chun Kim; Ki Myoung Kwon; Man Sig Lee; Myung Hwan Kim; Min A Bae - Web page: https://patentgrep.com/patent/US9433999B2 ## CPC - B22C 9/10: Cores; Manufacture or installation of cores {(breaker cores B22C9/084)} - B22C 1/10: for influencing the hardening tendency of the mould material (influencing the hardening tendency of the binding agent only B22C1/16) - B22C 1/188: {Alkali metal silicates} - B22C 13/12: for cores - B22C 15/24: involving blowing devices in which the mould material is supplied in the form of loose particles - B22D 29/001: {Removing cores} - C21D 1/60: Aqueous agents - B22C: FOUNDRY MOULDING (moulding refractory materials in general B28B) - B22D: CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES (shaping of plastics or substances in a plastic state B29C; metallurgical processing, selection of substances to be added to metal C21, C22) - C21D: MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING (surface treatment of metallic material involving at least one process provided for in class C23 and at least one process covered by this subclass C23F17/00; unidirectional solidification of eutectic materials or unidirectional demixing of eutectoid materials C30B) ## Abstract The present disclosure relates to a manufacturing method of a core using an inorganic binder, a core manufactured thereby, a manufacturing method of a casting product with a core using an inorganic binder, a casting product manufactured thereby, and a manufacturing system of a core using an inorganic binder. ## Claims ### Claim 1 A manufacturing method of a core using an inorganic binder, comprising: an original sand supplying step in which original molding sand is supplied to a muller; a mulling step in which the original molding sand is mixed and mulled with a liquid inorganic binder including water glass and mulled sand is prepared by the muller; a sand transferring step in which the mulled sand is transferred from the muller to a mulled sand hopper; a sand supplying step in which the mulled sand is supplied from the mulled sand hopper to a blowing head positioned under the mulled sand hopper; a blowing step in which the mulled sand supplied into the blowing head is blown into a core mold; a gas exhausting step in which the inside of the core mold is exhausted and depressurized; a curing step in which after the core mold is preheated, the inside of the blown core is cured and calcined; and an extracting step in which the core mold is separated and the cured core is extracted, wherein the inorganic binder includes the water glass of 40 to 70 parts by weight, nano-silica of 5 to 35 parts by weight, a Li-based water resistant additive of 0.1 to 10 parts by weight, an organic silicon compound of 0.1 to 10 parts by weight, and an anti-sand burning additive of 1 to 10 parts by weight. ### Claim 2 (depends on 1) The manufacturing method of a core using an inorganic binder according to claim 1, wherein the inorganic binder is mixed in an amount of 1 to 6 weight % with respect to the original molding sand. ### Claim 3 (depends on 1) The manufacturing method of a core using an inorganic binder according to claim 1, wherein the Li-based water resistant additive includes one or more selected from lithium carbonate, lithium silicate, lithium hydroxide, lithium sulfate, lithium bromide, and lithium acetate. ### Claim 4 (depends on 1) The manufacturing method of a core using an inorganic binder according to claim 1, wherein the organic silicon compound includes one or more selected from methyltriethoxysilane, sodium methylsiliconate, methyltrimethoxysilane, potassium methylsiliconate, butyltrimethoxysilane, and vinyltrimethoxysilane. ### Claim 5 (depends on 1) The manufacturing method of a core using an inorganic binder according to claim 1, wherein the anti-sand burning additive includes one or more selected from monosaccharides, polysaccharides, and disaccharides. ### Claim 6 (depends on 1) The manufacturing method of a core using an inorganic binder according to claim 1, wherein the original sand supplying step includes: a step of supplying the original sand measured to a predetermined amount from an original molding sand storage upper hopper to a sand measurement lower hopper; and a step of supplying the original sand from the sand measurement lower hopper to the muller. ### Claim 7 (depends on 6) The manufacturing method of a core using an inorganic binder according to claim 6, wherein the mulling step includes: a step of mulling the original molding sand supplied from the sand measurement lower hopper to the muller for 10 to 60 seconds; and a step of preparing mulled sand by being supplied with an inorganic binder from a binder supply device to the muller and mulling the inorganic binder for 30 to 120 seconds. ### Claim 8 (depends on 1) The manufacturing method of a core using an inorganic binder according to claim 1, wherein in the sand supplying step, the mulled sand is supplied from the mulled sand hopper to the blowing head positioned under the mulled sand hopper, and the supplied mulled sand is distributed to an upper end of a blowing nozzle plate by a mulled sand flow guider positioned at a lower end within the blowing head. ### Claim 9 (depends on 1) A core manufactured by using an inorganic binder by the manufacturing method of a core using an inorganic binder according to claim 1. ### Claim 10 (depends on 9) The core manufactured by using an inorganic binder according to claim 9, wherein when the core is exposed in an environment condition with an absolute humidity of 20 to 30 g/m3 for 3 hours, the core has a flexural strength of 60% or more with respect to an initial flexural strength. ### Claim 11 (depends on 10) The core manufactured by using an inorganic binder according to claim 10, wherein the initial flexural strength of the core is 150 N/cm2 or more. ### Claim 12 (depends on 1) A manufacturing method of a casting product with a core using an inorganic binder, comprising: a step of storing a core using an inorganic binder manufactured by the manufacturing method of a core according claim 1; a casting step of manufacturing a product by pouring molten metal of a predetermined material into a mold formed into a predetermined shape by using the stored core; a mechanical sand removing step of removing the core used in the casting step; and a heating step including a water-quenching process of the sand-removed product, wherein in the water-quenching process of the heating step, a chemical sand removal is performed by adding a chemically hydrolyzed solution to hydrolyze the inorganic binder remaining in the core after the mechanical sand removing step. ### Claim 13 (depends on 12) The manufacturing method of a casting product with a core using an inorganic binder according to claim 12, wherein the chemically hydrolyzed solution is a silicate solution including sodium silicate or sodium metasilicate, or a phosphate solution including sodium phosphate or disodium phosphate.