US3802902A
Expired / Lapsed
US
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Method of making molds
Assignee: Ti Tech International Inc
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Filing: 1972-03-17
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Granted: 1974-04-09
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Expires: 1992-03-17
Abstract
Abstract A method of making molds for use in casting highly reactive metals such as titanium, zirconium, hafnium, columbium, and alloys thereof in which granular graphite, olivine or mixtures thereof are mixed with a binder such as sodium silicate to form a mixture which is rammed into a flask about a pattern to form a mold. The mold is removed from the pattern with or without first hardening and is then baked at a temperature up to about 290* F. The mold is then coated with a thermally insulative coating which is nonreactive with the molten metal such as alumina in an acrylic binder. The mold is then ready for use or it can be stored indefinitely under conditions which prevent its picking up moisture.
Inventors
- 👤 D Turner
- 👤 W Lee
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:04
CPC Classifications
B; B22; B22C; B22C3/00; B22C1/00; B22C9/00; B22C9/12
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
20 words
The method of making a mold as set forth in claim 1 in which said water-soluble binder is sodium silicate.
Claim 2
Dependent Claim
37 words
The method of making a mold as set forth in claim 1 in which said mixture is shaped about a pattern to form a mold, and said mold is removed from said pattern before it is baked.
Claim 3
Dependent Claim
25 words
The method of making a mold as set forth in claim 3 in which said mold is hardened before it is removed from said pattern.
Claim 4
Dependent Claim
20 words
The method of making a mold as set forth in claim 1 in which said refractory powder is calcined alumina.
Claim 5
Dependent Claim
23 words
The method of making a mold as set forth in claim 5 in which the binder of said coating is an acrylic binder.
Claim 6
Dependent Claim
20 words
The method of making a mold as set forth in claim 1 in which said refractory material is powdered graphite.
Claim 7
Dependent Claim
26 words
The method of making a mold as seT forth in claim 1 in which said refractory material is a mixture of powdered graphite and olivine sand.
Claim 8
Dependent Claim
28 words
The method of making a mold as set forth in claim 8 in which the particle size of said refractory material ranges from about 50 to 150 AFS.
Claim 9
Dependent Claim
29 words
The method of making a mold as set forth in claim 8 in which said refractory material comprises substantially equal amounts by weight of graphite powder and olivine sand.
Claim 10
Dependent Claim
30 words
The method of making a mold as set forth in claim 8 in which said refractory material comprises 3 parts by weight olivine sand for each part of graphite powder.
Claim 11
Independent Claim
85 words
The method of making a mold which includes the steps of forming a mixture of powdered graphite, olivine sand and sodium silicate, adding water to and mulling said mixture, shaping a mold from said mulled mixture, baking said mold at a temperature above about 212*F but not higher than about 290*F to remove free water, and coating at least substantially the entire working surface of said baked mold with a thermally insulative coating about 0.001-0.005 inch thick formed of calcined alumina powder and a binder.
Claim 12
Dependent Claim
37 words
The method of making a mold as set forth in claim 12 in which said mulled mixture is forced about a pattern to form said mold, and said mold is removed from said pattern prior to baking.
Claim 13
Dependent Claim
25 words
The method of making a mold as set forth in claim 13 in which said mold is hardened before it is removed from said pattern.
Claim 14
Dependent Claim
27 words
The method of making a mold as set forth in claim 13 in which said insulative coating is formed of calcined alumina powder and an acrylic binder.
Claim 15
Dependent Claim
28 words
The method of making a mold as set forth in claim 15 in which said mixture comprises substantially equal parts by weight of powdered graphite and olivine sand.
Claim 16
Dependent Claim
31 words
The method of making a mold as set forth in claim 15 in which said mixture comprises substantially 3 parts by weight of olivine sand for each part of graphite powder.
Claim 17
Dependent Claim
27 words
The method of making a mold as set forth in claim 12 in which the particle size of said mixture ranges from about 50 to 150 AFS.
Claim 18
Dependent Claim
42 words
The method of making a mold as set forth in claim 12 in which the particle size of said powdered graphite ranges from about 50 to 75 AFS, and the particle size of said olivine sand ranges from about 70 to 150.
Claim 19
Independent Claim
83 words
The method of making a mold which includes the steps of forming a mixture of olivine sand and sodium silicate, adding water to and mulling said mixture, shaping a mold from said mulled mixture, baking said mold at a temperature above about 212*F but not higher than about 290*F to remove free water, and coating at least substantially the entire working surface of said baked mold with a thermally insulative coating about 0.001-0.005 inch thick formed of calcined alumina powder and a binder.
Claim 20
Independent Claim
100 words
The method of making a mold which includes the steps of forming a mixture of (a) a refractory material selected from the group consisting of granular graphite, olivine sand and combinations thereof, (b) a water-soluble binder selected from the group consisting of sodium silicate and potassium silicate, and (c) water, shaping a mold from said mixture, baking said mold at a temperature above about 212*F but not higher than about 290*F to remove free water, and coating substantially the entire working surface of said mold with a thermally insulative coating formed of a fine refractory powder and an acrylic binder.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-04-08 | 1977-10-08 | 1978-04-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-08 | 1981-10-08 | 1982-04-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-08 | 1985-10-08 | 1986-04-09 | $7700.00 | Window Closed / Lapsed |