Method for removing refractory metal cores

Patent metadata

Field	Value
Publication number	US-11673188-B2
Application number	US-202217676430-A
Country	US
Kind code	B2
Filing date	Feb 21, 2022
Priority date	Mar 12, 2020
Publication date	Jun 13, 2023
Grant date	Jun 13, 2023

Abstract

A furnace for removing a molybdenum-alloy refractory metal core through sublimation comprising a retort furnace having an interior; a sublimation fixture insertable within the interior of the retort furnace, the sublimation fixture configured to receive at least one turbine blade having the molybdenum-alloy refractory metal core; a flow passage thermally coupled to the retort furnace configured to heat a fluid flowing through the flow passage and deliver the fluid to the molybdenum-alloy refractory metal core causing sublimation of the molybdenum-alloy refractory metal core.

First claim

What is claimed is:

1. A process for removing a molybdenum-alloy refractory metal core from a turbine blade through sublimation comprising:
installing at least one turbine blade in a sublimation fixture;
installing said sublimation fixture in an interior of a retort furnace, a flow passage thermally coupled to said retort furnace configured to heat air flowing through said flow passage and deliver said heated air to a molybdenum-alloy refractory metal core;
supplying the air from an air source to a coupling fluidly coupled to said flow passage;
heating said air flowing through said flow passage;
supplying said heated air from said flow passage to a junction; coupling said junction to said sublimation fixture;
removing the molybdenum-alloy refractory metal core from said at least one turbine blade through sublimation with said heated air; and
capturing waste discharged from the blade responsive to sublimation of said molybdenum-alloy refractory metal core responsive to said sublimation.

2. The process of claim 1 , further comprising:
reusing said waste; and
disposing of said waste.

3. The process of claim 1 , further comprising:
prior to the step of installing at least one turbine blade in a sublimation fixture casting said at least one blade with a ceramic core and said molybdenum-alloy refractory metal core; and
removing said ceramic core.

4. The process of claim 1 , further comprising:
flowing said heated air through said sublimation fixture into said at least one turbine blade; and
flowing said heated air through said turbine blade;
contacting said molybdenum-alloy refractory metal core with said heated air.

5. The process of claim 4 , wherein said heated air is heated to a temperature of from 1300 degrees Fahrenheit to 2000 degrees Fahrenheit.

6. The process of claim 1 , the step of installing said sublimation fixture in a retort furnace further comprising:
the retort furnace comprises an outer furnace box having an interior and an inner furnace box within said interior, said inner furnace box comprising an enclosure coupled to a base; and
inserting the sublimation fixture within said inner furnace box.

Assignees

• Raytheon Tech Corp

Inventors

• Bales Daniel A
• Demichael Thomas

Classifications

• F27B5/00

  Muffle furnaces; Retort furnaces; Other furnaces in which the charge is held completely isolated (furnaces through which the charge is moved mechanically or in which the charge moves by gravity F27B9/00) · CPC title

• F27B5/16

  Arrangements of air or gas supply devices · CPC title

• F27B5/02

  of multiple-chamber type · CPC title

• F27B5/06

  Details, accessories or equipment specially adapted for furnaces of these types · CPC title

• F27D7/02

  Supplying steam, vapour, gases or liquids · CPC title