Method for manufacturing a shell mould for the manufacture of aeronautical metal components by lost-wax casting

Patent metadata

Field	Value
Publication number	US-12202033-B2
Application number	US-202218698138-A
Country	US
Kind code	B2
Filing date	Sep 29, 2022
Priority date	Oct 7, 2021
Publication date	Jan 21, 2025
Grant date	Jan 21, 2025

Abstract

A method for manufacturing a shell mold intended for manufacturing at least one metal part by lost-wax casting, the shell mold including at least one molding cavity intended for molding the metal part, and at least one feed channel intended to convey a liquid metal to the molding cavity, the method including manufacturing a wax pattern including a part pattern intended to form the molding cavity and a feed channel pattern intended to form the feed channel, arranging at least one ceramic insert around at least a portion of the feed channel pattern, and manufacturing the shell mold around the wax pattern.

First claim

The invention claimed is:

1. A method for manufacturing a shell mold intended for manufacturing at least one metal part by lost-wax casting, the shell mold comprising at least one molding cavity intended for molding the metal part, and at least one feed channel intended to convey a liquid metal to the molding cavity, the method comprising:
manufacturing a wax pattern comprising a part pattern intended to form the molding cavity and a feed channel pattern intended to form the feed channel,
arranging at least one ceramic insert around at least one portion of the feed channel pattern,
manufacturing the shell mold around the wax pattern.

2. The method as claimed in claim 1 , in which manufacturing the wax pattern comprises injecting a liquid wax into an intermediate mold and then hardening the wax and, before injecting the liquid wax, arranging the at least one ceramic insert in the intermediate mold such that, after the wax has hardened, the insert is arranged around at least a portion of the feed channel pattern.

3. The method as claimed in claim 1 , in which the insert comprises a body in the form of a ring surrounding the feed channel pattern.

4. The method as claimed in claim 3 , in which the body of the insert has an inner diameter equal to an outer diameter of the feed channel pattern intended to form the feed channel of the shell mold.

5. The method as claimed in claim 3 , in which an axial length of the body of the insert is substantially equal to half an axial length of the feed channel pattern around which the insert is arranged, along a central axis of the feed channel pattern.

6. The method as claimed in claim 3 , in which an inner wall of the body of the insert comprises a neck.

7. The method as claimed in claim 3 , in which the insert comprises at least one annular anchoring bead arranged around the body of the insert.

8. The method as claimed in claim 7 , in which the anchoring bead is arranged at an axial end of the body of the insert, or in an intermediate position between two axial ends of the body of the insert.

9. The method as claimed in claim 7 , in which the anchoring bead has a straight portion extending radially from the body of the insert, and a toroidal portion arranged around the straight portion.

10. The method as claimed in claim 7 , in which the anchoring bead extends radially from the body of the insert by at least 3 mm.

11. The method as claimed in claim 1 , in which the ceramic insert is manufactured by additive manufacturing.

12. The method as claimed in claim 1 , in which the shell mold is intended for manufacturing a cluster of metal turbomachine parts, the shell mold being axisymmetric about a central axis and comprising a plurality of molding cavities each intended to mold one of the metal parts, the feed channel comprising a central feed channel descending along the central axis of the mold and configured to receive molten metal at a top end, and a plurality of source feed ducts each bringing a bottom end of the central feed channel into fluid communication with a base of each of the molding cavities, a plurality of ceramic inserts being arranged in the intermediate mold such that, after the wax has hardened, each of the inserts is arranged around at least a portion of a source feed duct pattern around which one of the source feed ducts of the shell mold is intended to be formed.

13. A shell mold intended for manufacturing a metal turbomachine part, obtained by a method as claimed in claim 1 .

14. A method for manufacturing metal turbomachine parts using a shell mold obtained by a method as claimed in claim 1 .

Assignees

• Safran

Inventors

• Long Ming
• Niane Ngadia Taha
• Joubert Hugues Denis
• Hachani Heni

Classifications

• B22C9/08

  Features with respect to supply of molten metal, e.g. ingates, circular gates, skim gates · CPC title

• B22C9/04

  Use of lost patterns · CPC title

• B33Y80/00

  Products made by additive manufacturing · CPC title

• B22C9/082

  Sprues, pouring cups · CPC title

• B29C67/241

  Moulding wax · CPC title