US3870529A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of producing casting moulds for precision casting
Assignee: Hitachi Ltd
•
Filing: 1973-03-19
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Granted: 1975-03-11
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Expires: 1993-03-19
Abstract
Abstract A method of producing casting moulds for use in the precision casting, in which a slurry of refractory material is prepared by mixing a powdered refractory material, a binder obtained by the hydrolysis of ethyl silicate with an amount of water smaller than the theoretical hydrolysis amount, and a small amount of a gelling promoting agent, said slurry of refractory material being poured into a shaping mould, and after said slurry has gelled in said shaping mould, the resultant casting mould is removed from said shaping mould and immersed in a hardening water containing a surface active agent or a water-soluble silicasol or both therein, whereby said casting mould is completely hardened, following which said hardened casting mould is dried and calcined.
Inventors
- 👤 Takeomi Okumoto
- 👤 Hiroshi Ueda
- 👤 Junji Sakai
- 👤 Yogo Shimada
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 21:19
CPC Classifications
B; B22; B22C; B22C1/00; B22C1/16; B22C1/20; B22C1/205
Claims Analysis
Total Claims: 39
Claim 1
Independent Claim
142 words
A METHOD FOR PRODUCING A CASTING MOULD FOR USE IN PRECISION CASTING COMPRISING PREPARING A FLOWABLE REFRACTORY SLURRY COMPRISING A MIXTURE OF A POWDERED REFRACTORY MATERIAL, A BINDER OBTAINED BY THE HYDROLYSIS OF ETHYL SILICATE WITH AN AMOUNT OF WATER SMALLER THAN THE THEORETICAL HYDROLYSIS AMOUNT OF WATER, AND SUFFICIENT AMOUNT OF A GELLING PROMOTING AGENT SO THAT GELLING WILL COMMENCE IS ABOUT 6 TO 8 MINUTES AFTER SAID SLURRY IS POURED INTO A SHAPING MOULD; POURING SAID FLOWABLE REFRACTORY SLURRY INTO A SHAPING MOULD; REMOVING THE RESULTANT CASTING MOULD FROM SAID SHAPING MOULD AFTER SAID SLURRY HAS GELLED; IMMERSING SAID CASTING MOULD IN A HARDENING WATER CONTAINING SUFFICIENT SURFACE ACTIVE AGENT THEREIN TO DECREASE THE SURFACE TENSION OF SAID HARDENING WATER TO THEREBY COMPLETELY HARDEN SAID CASTING MOULD, AND THEN DRYING AND CALCINING SAID CASTING MOULD TO OBTAIN SAID CASTING MOULD.
Claim 2
Independent Claim
142 words
A METHOD FOR PRODUCING A CASTING MOULD FOR USE IN PRECISION CASTING COMPRISING PREPARING A FLOWABLE REFRACTORY SLURRY COMPRISING A MIXTURE OF A POWDERED REFRACTORY MATERIAL, A BINDER OBTAINED BY THE HYDROLYSIS OF ETHYL SILICATE WITH AN AMOUNT OF WATER SMALLER THAN THE THEORETICAL HYDROLYSIS AMOUNT OF WATER, AND SUFFICIENT AMOUNT OF A GELLING PROMOTING AGENT SO THAT GELLING WILL COMMENCE IS ABOUT 6 TO 8 MINUTES AFTER SAID SLURRY IS POURED INTO A SHAPING MOULD; POURING SAID FLOWABLE REFRACTORY SLURRY INTO A SHAPING MOULD; REMOVING THE RESULTANT CASTING MOULD FROM SAID SHAPING MOULD AFTER SAID SLURRY HAS GELLED; IMMERSING SAID CASTING MOULD IN A HARDENING WATER CONTAINING SUFFICIENT SURFACE ACTIVE AGENT THEREIN TO DECREASE THE SURFACE TENSION OF SAID HARDENING WATER TO THEREBY COMPLETELY HARDEN SAID CASTING MOULD, AND THEN DRYING AND CALCINING SAID CASTING MOULD TO OBTAIN SAID CASTING MOULD.
Claim 3
Independent Claim
143 words
A method for producing a casting mould for use in precision casting comprising preparing a flowable refractory slurry comprising a mixture of a powdered refractory material, a binder obtained by the hydrolysis of ethyl silicate with an amount of water smaller than the theoretical hydrolysis amount of water, and a sufficient amount of a gelling promoting agent so that gelling will commence is about 6 to 8 minutes after said slurry is poured into a shaping mould; pouring said flowable refractory slurry into a shaping mould; removing the resultant casting mould from said shaping mould after said slurry has gelled; immersing said casting mould in a hardening water containing sufficient surface active agent thereIn to decrease the surface tension of said hardening water to thereby completely harden said casting mould; and then drying and calcining said casting mould to obtain said casting mould.
Claim 4
Independent Claim
143 words
A method for producing a casting mould for use in precision casting comprising preparing a flowable refractory slurry comprising a mixture of a powdered refractory material, a binder obtained by the hydrolysis of ethyl silicate with an amount of water smaller than the theoretical hydrolysis amount of water, and a sufficient amount of a gelling promoting agent so that gelling will commence is about 6 to 8 minutes after said slurry is poured into a shaping mould; pouring said flowable refractory slurry into a shaping mould; removing the resultant casting mould from said shaping mould after said slurry has gelled; immersing said casting mould in a hardening water containing sufficient surface active agent thereIn to decrease the surface tension of said hardening water to thereby completely harden said casting mould; and then drying and calcining said casting mould to obtain said casting mould.
Claim 5
Dependent Claim
35 words
A method for producing casting moulds for use in precision casting according to claim 1, in which the casting mould removed from the shaping mould is immersed in hardening water containing a water-soluble silica sol.
Claim 6
Dependent Claim
40 words
A method for producing casting moulds for use in precision casting according to claim 1, in which the casting mould removed from the shaping mould is immersed in hardening water containing a surface active agent and a water-soluble silica sol.
Claim 7
Dependent Claim
24 words
The method according to claim 1, wherein the gelling promoting agent is selected from the group consisting of ammonium carbonate, triethanolamine, pyridine and piperidine.
Claim 8
Dependent Claim
31 words
The method according to claim 1, wherein said surface active agent is selected from the group consisting of anion active agents, cation active agents, nonionic active agents and ampholytic active agents.
Claim 9
Dependent Claim
13 words
The method according to claim 1, wherein said slurry is an alcohol slurry.
Claim 10
Dependent Claim
29 words
The method according to claim 1, wherein said refractory material is selected from the group consisting of Zircon sand powder, Chamotte powder, sintered Zircon sand powder and fused silica.
Claim 11
Dependent Claim
14 words
The method according to claim 1, wherein said gelling promoting agent is ammonium carbonate.
Claim 12
Dependent Claim
25 words
The method according to claim 1, wherein about 1,300 to 2,000 c.c. of said binder is mixed with each 10 kg, of said refractory material.
Claim 13
Dependent Claim
29 words
The method according to claim 1, wherein the amount of said binder is sufficient so that said casting mould has a deflective strength of at least about 40 kg/cm2.
Claim 14
Dependent Claim
27 words
The method according to claim 1, wherein the amount of water in said binder is about 50 to 70 percent of the theoretical hydrolysis amount of water.
Claim 15
Dependent Claim
29 words
The method according to claim 1, wherein said refractory slurry consists essentially of a mixture of said powdered refractory material, said binder, said gelling promoting agent and acidified alcohol.
Claim 16
Dependent Claim
25 words
The method according to claim 1, wherein said surface active agent is selected from the group consisting of a cation active agent of the formula:
Claim 17
Independent Claim
123 words
A method for producing a casting mould useful for precision casting comprising preparing a flowable refractory slurry consisting essentially of a mixture of Zircon sand powder, a binder obtained by the hydrolysis of ethyl silicate with an amount of water less than the theoretical hydrolysis amount of water and an aqueous solution of ammonium carbonate; pouring said flowable refractory slurry into a shaping mould; removing the resultant casting mould from said shaping mould after the slurry has gelled; immersing said casting mould in hardening water containing a cationic surface active agent therein to thereby completely harden said casting mould; drying said casting mould; then calcining said casting mould at a temperature of about 900*C. to obtain said casting mould useful for precision casting.
Claim 18
Independent Claim
123 words
A method for producing a casting mould useful for precision casting comprising preparing a flowable refractory slurry consisting essentially of a mixture of Zircon sand powder, a binder obtained by the hydrolysis of ethyl silicate with an amount of water less than the theoretical hydrolysis amount of water and an aqueous solution of ammonium carbonate; pouring said flowable refractory slurry into a shaping mould; removing the resultant casting mould from said shaping mould after the slurry has gelled; immersing said casting mould in hardening water containing a cationic surface active agent therein to thereby completely harden said casting mould; drying said casting mould; then calcining said casting mould at a temperature of about 900*C. to obtain said casting mould useful for precision casting.
Claim 19
Dependent Claim
42 words
The method according to claim 14, wherein the amount of aqueous solution of ammonium carbonate in said flowable refractory slurry is sufficient so that gelling will commence in about 6 to 8 minutes after said slurry is poured into said shaping mould.
Claim 20
Dependent Claim
28 words
The method according to claim 14, wherein the amount of binder is sufficient so that said casting mould has a deflective strength of at least about 40 kg/cm2.
Claim 21
Dependent Claim
14 words
The method according to claim 14, wherein said surface active agent has a formula:
Claim 22
Dependent Claim
15 words
The method according to claim 14, wherein said flowable refractory slurry is an alcohol slurry.
Claim 23
Independent Claim
121 words
A method for producing a casting mould useful for precision casting comprising preparing a flowable refractory sLurry consisting essentially of a mixture of Chamotte powder, a binder obtained by the hydrolysis of ethyl silicate with an amount of water less than the theoretical hydrolysis amount of water, and an aqueous solution of ammonium carbonate; pouring said flowable refractory slurry into a shaping mould; removing the resultant casting mould from said shaping mould after the slurry has gelled; immersing said casting mould in hardening water containing a nonionic surface active agent to thereby completely harden said casting mould; drying said casting mould; and calcining said casting mould at a temperature of about 400*C. to obtain said casting mould useful for precision casting.
Claim 24
Independent Claim
121 words
A method for producing a casting mould useful for precision casting comprising preparing a flowable refractory sLurry consisting essentially of a mixture of Chamotte powder, a binder obtained by the hydrolysis of ethyl silicate with an amount of water less than the theoretical hydrolysis amount of water, and an aqueous solution of ammonium carbonate; pouring said flowable refractory slurry into a shaping mould; removing the resultant casting mould from said shaping mould after the slurry has gelled; immersing said casting mould in hardening water containing a nonionic surface active agent to thereby completely harden said casting mould; drying said casting mould; and calcining said casting mould at a temperature of about 400*C. to obtain said casting mould useful for precision casting.
Claim 25
Dependent Claim
42 words
The method according to claim 19, wherein the amount of aqueous solution of ammonium carbonate in said flowable refractory slurry is sufficient so that gelling will commence in about 6 to 8 minutes after said slurry is poured into said shaping mould.
Claim 26
Dependent Claim
28 words
The method according to claim 19, wherein the amount of binder is sufficient so that said casting mould has a deflective strength of at least about 40 kg/cm2.
Claim 27
Dependent Claim
15 words
The method according to claim 19, wherein said surface active agent has a formula: CH3(CH2)11O(CH2CH2O)3H
Claim 28
Dependent Claim
15 words
The method according to claim 19, wherein said flowable refractory slurry is an alcohol slurry.
Claim 29
Independent Claim
124 words
A method for producing a casting mould useful for precision casting comprising preparing a flowable refractory slurry comprising a mixture of Zircon sand sintered powder, Zircon said powder, a binder obtained by the hydrolysis of ethyl silicate with an amount of water less than the theoretical hydrolysis amount of water, and an aqueous solution of ammonium carbonate; pouring said flowable refractory slurry into a shaping mould; removing the resultant casting mould from said shaping mould after the slurry has gelled; immersing the casting mould in hardening water containing a silica sol aqueous solution to thereby completely harden said casting mould; drying said casting mould; and calcining said casting mould at a temperature of about 950*C. to obtain said casting mould useful for precision casting.
Claim 30
Independent Claim
124 words
A method for producing a casting mould useful for precision casting comprising preparing a flowable refractory slurry comprising a mixture of Zircon sand sintered powder, Zircon said powder, a binder obtained by the hydrolysis of ethyl silicate with an amount of water less than the theoretical hydrolysis amount of water, and an aqueous solution of ammonium carbonate; pouring said flowable refractory slurry into a shaping mould; removing the resultant casting mould from said shaping mould after the slurry has gelled; immersing the casting mould in hardening water containing a silica sol aqueous solution to thereby completely harden said casting mould; drying said casting mould; and calcining said casting mould at a temperature of about 950*C. to obtain said casting mould useful for precision casting.
Claim 31
Dependent Claim
42 words
The method according to claim 24, wherein the amount of aqueous solution of ammonium carbonate in said flowable refractory slurry is sufficient so that gelling will commence in about 6 to 8 minutes after said slurry is poured into said shaping mould.
Claim 32
Dependent Claim
28 words
The method according to claim 24, wherein the amount of binder is sufficient so that said casting mould has a deflective strength of at least about 40 kg/cm2.
Claim 33
Dependent Claim
15 words
The method according to claim 24, wherein said flowable refractory slurry is an alcohol slurry.
Claim 34
Independent Claim
124 words
A method for producing a casting mould useful for precision casting comprising preparing a flowable refractory slurry of a mixture of fused silica, a binder obtained by the hydrolysis of ethyl silicate with an amount of water less than the theoretical hydrolysis amount of water, and an aqueous solution of ammonium carbonate; pouring said flowable refractory slurry into a shaping mould; removing the resultant casting mould from said shaping mould after the slurry has gelled; immersing the casting mould in hardening water containing a water-soluble silica sol and a nonionic surface active agent to thereby completely harden said casting mould; drying said casting mould; and calcining said casting mould at a temperature of about 1,000*C. to obtain said casting mould useful for precision casting.
Claim 35
Independent Claim
124 words
A method for producing a casting mould useful for precision casting comprising preparing a flowable refractory slurry of a mixture of fused silica, a binder obtained by the hydrolysis of ethyl silicate with an amount of water less than the theoretical hydrolysis amount of water, and an aqueous solution of ammonium carbonate; pouring said flowable refractory slurry into a shaping mould; removing the resultant casting mould from said shaping mould after the slurry has gelled; immersing the casting mould in hardening water containing a water-soluble silica sol and a nonionic surface active agent to thereby completely harden said casting mould; drying said casting mould; and calcining said casting mould at a temperature of about 1,000*C. to obtain said casting mould useful for precision casting.
Claim 36
Dependent Claim
42 words
The method according to claim 28, wherein the amount of aqueous solution of ammonium carbonate in said flowable refractory slurry is sufficient so that gelling will commence in about 6 to 8 minutes after said slurry is poured into said shaping mould.
Claim 37
Dependent Claim
28 words
The method according to claim 28, wherein the amount of binder is sufficient so that said casting mould has a deflective strength of at least about 40 KG/CM2.
Claim 38
Dependent Claim
15 words
The method according to claim 28, wherein said surface active agent has the formula: CH3(CH2)11O(CH2CH2O)3H
Claim 39
Dependent Claim
15 words
The method according to claim 28, wherein said flowable refractory slurry is an alcohol slurry.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-03-10 | 1978-09-09 | 1979-03-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-03-10 | 1982-09-09 | 1983-03-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-03-10 | 1986-09-09 | 1987-03-11 | $7700.00 | Window Closed / Lapsed |