System and methods for removing core elements of cast components

Patent metadata

Field	Value
Publication number	US-9808862-B2
Application number	US-201715590132-A
Country	US
Kind code	B2
Filing date	May 9, 2017
Priority date	Dec 19, 2013
Publication date	Nov 7, 2017
Grant date	Nov 7, 2017

Abstract

A system and methods are provided for removing core elements of cast components. In one embodiment, a method includes controlling a first high temperature autoclave cycle for a cast component in a vessel with a first solution concentration to remove at least a first portion of core elements, wherein the first solution concentration, temperature and pressure in the vessel are controlled to expose one or more casting pins in the cast component. The method may also include controlling a second high temperature autoclave cycle for the cast component in the vessel with second solution concentration, wherein the second solution concentration, temperature and pressure in the vessel during the second high temperature autoclave cycle are controlled to loosen one or more of the casting pins from the cast component, and controlling one or more low temperature autoclave cycles to remove core and casting pins from the cast component.

First claim

What is claimed is:

1. A method for removing core elements of cast components, the method comprising the acts of:
controlling a first high temperature autoclave cycle for a cast component in a vessel with a first solution concentration to remove at least a first portion of core elements, wherein the first solution concentration, temperature and pressure in the vessel are controlled to expose one or more casting pins in the cast component;
controlling a second high temperature autoclave cycle for the cast component in the vessel with second solution concentration, wherein the second solution concentration, temperature and pressure in the vessel during the second high temperature autoclave cycle are controlled to loosen one or more of the casting pins from the cast component; and
controlling one or more low temperature autoclave cycles following the second high temperature cycle to remove core and casting pins from the cast component, wherein the one or more low temperature autoclave cycles have a temperature lower than the first high temperature autoclave cycle and the first high temperature autoclave cycle has a temperature lower than the second high temperature autoclave cycle.

2. The method of claim 1 , wherein the first high temperature autoclave cycle includes heating the vessel to a temperature within the range of 200 to 400 degrees F.

3. The method of claim 1 , wherein the solution of the first high temperature autoclave cycle is solution of less than 40% of KOH or less than 40% of NaOH.

4. The method of claim 1 , wherein the second high temperature autoclave cycle includes heating the vessel to a temperature within the range of 400 to 600 degrees F.

5. The method of claim 1 , wherein the solution of the second high temperature autoclave cycle is solution of at least 40% of KOH or at least 40% of NaOH.

6. The method of claim 1 , wherein each high temperature autoclave cycle includes a cooling cycle that is controlled to cycled on and off multiple times during each autoclave cycle to provide repetitive and rapid pressure changes in the vessel, promote agitation, and promote a flushing action in the solution.

7. The method of claim 1 , wherein 3-5 low temperature autoclave cycles are initiated in the vessel.

8. The method of claim 1 , wherein the autoclave cycles are controlled to remove core elements including ceramic cores and alumina casting pins.

9. The method of claim 1 , wherein the autoclave cycles are initiated in a vessel having a volume within the range of 1-50 gallons.

10. The method of claim 1 , wherein the each autoclave cycle includes flushing the cast component with a fluid to remove one or more of core and casting pin material.

Assignees

• United Technologies Corp

Inventors

• Verner Carl R
• Marcin John Joseph

Classifications

• B22D29/002

  by leaching, washing or dissolving · CPC title

• B22D30/00

  Cooling castings, not restricted to casting processes covered by a single main group (accessories for cooling cast stock in continuous casting of metals B22D11/124; controlling or regulating processes or operations for cooling cast stock or mould in continuous casting of metals B22D11/22; chill casting B22D15/00) · CPC title

• B22D29/00

  Removing castings from moulds, not restricted to casting processes covered by a single main group; Removing cores; Handling ingots {(B22D13/10, B22D11/124, B22D17/00 take precedence)} · CPC title

• B22D29/003 Primary

  using heat · CPC title

• B22D29/006

  by abrasive, water or air blasting · CPC title