US3598167A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and means for the production of columnar-grained castings
Assignee: RTX Corp
•
Filing: 1968-11-01
•
Granted: 1971-08-10
•
Expires: 1988-11-01
Abstract
Abstract A method and materials for producing shell molds for casting columnar grained metal components wherein a pattern is prepared corresponding to the shape of casting to be formed. The pattern is then combined with a base formed of a material selected from the group consisting of graphite and a refractory of high thermal conductivity. A shell mold is formed around the assembly comprising the pattern and base followed by removal of the pattern material to provide the shell mold. The base operates to conduct heat away from molten metal poured therein at a rate greater than the surrounding mold walls whereby nucleation will begin in the area adjacent the base and columnar grain growth will occur. The base included in the assembly of the pattern and base can also be used for connecting supporting rods to lend stability to an arrangement which includes a plurality of the assemblies whereby dip coating for formation of the shell mold can proceed without the need for a supporting baseplate.
Inventors
- 👤 Michael H Snyderman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:17
CPC Classifications
B; B22; B22C; B22C9/00; B22C9/02; B22C9/04
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
171 words
A method for the production of a cast columnar-grained metal component comprising the steps of preparing a pattern corresponding to the shape of the casting to be formed and having a bottom surface, forming against the bottom surface of said pattern a base formed of a material selected from the group consisting of graphite and high thermal conductivity refractory, said base having a surface corresponding in shape to the base surface of the pattern and in contact therewith, building up mold walls of sufficient thickness and strength about the assembly comprising the pattern and the base to form a shell mold thereabout, leaving exposed the surface of the base opposite to the pattern and then removing the pattern material from the mold to provide a shell mold, said base forming the bottom wall of the mold and operating to remove heat from molten metal poured into the formed shell mold at a rate greater than the surrounding mold walls to promote nucleation of the metal adjacent the surface of the base.
Claim 2
Independent Claim
171 words
A method for the production of a cast columnar-grained metal component comprising the steps of preparing a pattern corresponding to the shape of the casting to be formed and having a bottom surface, forming against the bottom surface of said pattern a base formed of a material selected from the group consisting of graphite and high thermal conductivity refractory, said base having a surface corresponding in shape to the base surface of the pattern and in contact therewith, building up mold walls of sufficient thickness and strength about the assembly comprising the pattern and the base to form a shell mold thereabout, leaving exposed the surface of the base opposite to the pattern and then removing the pattern material from the mold to provide a shell mold, said base forming the bottom wall of the mold and operating to remove heat from molten metal poured into the formed shell mold at a rate greater than the surrounding mold walls to promote nucleation of the metal adjacent the surface of the base.
Claim 3
Dependent Claim
49 words
A method in accordance with claim 1 wherein said base is formed to a configuration conforming with the bottom wall of the pattern and the surface of the base opposite to the bottom wall of the pattern is exposed by the mold for effective heat removal through said base.
Claim 4
Dependent Claim
59 words
A method in accordance with claim 2 wherein said assembly is formed by first preparing said pattern, providing mold walls around the bottom of the pattern whereby the pattern bottom serves as the bottom wall of said last mentioned mold, and introducing material for forming said base into said last mentioned mold for securing the base to the pattern.
Claim 5
Dependent Claim
42 words
A method in accordance with claim 2 including the step of providing a mold conforming to the shape of said base, molding said base, and thereafter applying said pattern material to said base for forming the assembly comprising the pattern and base.
Claim 6
Dependent Claim
23 words
A method in accordance with claim 1 wherein a shell molding process is followed for investing said mold around said pattern and base.
Claim 7
Dependent Claim
27 words
A method in accordance with claim 1 including the step of locating nucleating agents on said base prior to the introduction of molten metal into said mold.
Claim 8
Dependent Claim
88 words
A construction for the production of cast columnar-grained metal components comprising an assembly consisting of a disposable pattern corresponding to the shape of the casting to be formed and having a bottom wall and a base engaging and conforming to the bottom wall of said pattern, said base being selected from the group consisting of graphite and high thermal conductivity refractory, and a shell mold built up around said assembly, leaving exposed as the bottom wall of the mold, the surface of the base opposite to the pattern.
Claim 9
Dependent Claim
88 words
A construction for the production of cast columnar-grained metal components comprising an assembly consisting of a disposable pattern corresponding to the shape of the casting to be formed and having a bottom wall and a base engaging and conforming to the bottom wall of said pattern, said base being selected from the group consisting of graphite and high thermal conductivity refractory, and a shell mold built up around said assembly, leaving exposed as the bottom wall of the mold, the surface of the base opposite to the pattern.
Claim 10
Dependent Claim
32 words
A construction in accordance with claim 7 wherein said base is formed by solidification against the bottom wall of the pattern to a configuration conforming with the bottom wall of the pattern.
Claim 11
Dependent Claim
68 words
A construction in accordance with claim 7 wherein a plurality of said assemblies are secured together prior to application of the mold material, and including supporting rod means extending between the base portion of the assemblies, said rod means being formed of nondisposable material whereby the rod means operate to support the respective base portions relative to the mold after removal of the pattern material from the mold.
Claim 12
Dependent Claim
39 words
A construction in accordance with claim 7 including pin means secured to said base and extending outwardly therefrom, said pin means extending into the mold material invested around the base for thereby securing said mold relative to said base.
Claim 13
Dependent Claim
35 words
A method in accordance with claim 1 including the step of positioning the mold on a chill plate with the base in contact with the chill plate prior to introducing molten metal into the mold.
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) | 1974-08-09 | 1975-02-08 | 1975-08-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-09 | 1979-02-08 | 1979-08-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-09 | 1983-02-08 | 1983-08-10 | $7700.00 | Window Closed / Lapsed |