AS-CAST SHROUD SLOTS WITH PRE-SWIRLED LEAKAGE

• US 20110182726A1
• Filed: 01/25/2010
• Published: 07/28/2011
• Est. Priority Date: 01/25/2010
• Status: Abandoned Application

• Current Assignee: United Technologies Corporation (Rtx Corporation)
• Original Assignee: United Technologies Corporation (Rtx Corporation)
• Inventors: McCaffrey, Michael G.
• Application Number:
  US12/692,718
• Publication Number:
  US 20110182726A1
• Time in Patent Office: Days
• US Class Current: 415/208.2
• CPC Class Codes: B22C 9/04 Use of lost patterns
• CPC Class Codes: F01D 11/005 Sealing means between non relatively rotating elements
• CPC Class Codes: F01D 5/225 by shrouding
• CPC Class Codes: F01D 9/041 using blades F01D5/148 takes precedence
• CPC Class Codes: F05D 2230/21 by casting
• CPC Class Codes: F05D 2240/57 Leaf seals

Abstract

A system for forming a seal slot in a shroud assembly has a first element having a longitudinally extending slot and a second element having a longitudinally extending slot for receiving a portion of the first element. The first element has a pair of opposed surfaces and the second element has a pair of opposed surfaces which are oriented at an angle to the surfaces of the first element. The second element may have a planar portion and a curved portion adjacent the planar portion for forming a slot which allows a flow of fluid to exit the slot at a desired angle.

Claims

1. A system for forming a seal slot in a shroud assembly, said system comprising a first element having a longitudinally extending slot and a second element having a non-planar portion and a longitudinally extending slot for receiving a portion of said first element.

2. The system of claim 1, wherein said first element has a pair of opposed surfaces and said second element has a pair of opposed surfaces which are oriented at an angle with respect to said surfaces of said first element.

3. The system of claim 1, wherein said second element has a planar portion and said non-planar portion comprises a curved portion adjacent said planar portion.

4. The system of claim 1, wherein said first element has a first length and said second element has a second length greater than said first length.

5. The system of claim 1, wherein each of said first and second elements is formed from a refractory metal material.

6. The system of claim 1, wherein said second element has a portion with a twist.

7. A turbine engine component comprising:

a plurality of airfoils;

an as-cast shroud surrounding said airfoils; and

said as-cast shroud having a tailored segmentation with a curvature which alters the leakage flow to be more aligned with the rotating flow.

8. The turbine engine component of claim 7, wherein said tailored segmentation has a linear portion adjacent a first edge of said shroud and an angled portion adjacent a second opposed edge of said shroud.

9. The turbine engine component of claim 8, wherein said angled portion of said slot has an angle sufficient to turn said fluid flow to match a rotational flow about said turbine engine component.

10. A process for forming a turbine engine component comprising the steps of:

placing a refractory core assembly comprising a first element and a second element having a non-planar portion joined to said first element in a die;

encapsulating said refractory core assembly in a wax pattern having the form of said turbine engine component;

forming a ceramic shell mold about said wax pattern;

removing said wax pattern; and

pouring molten material into said ceramic shell mold to form said turbine engine component.

11. The process of claim 10, wherein said refractory core assembly placing step comprises placing a refractory core assembly wherein said first element is fitted into a slot in said second element and said second element is fitted into a slot in said first element.

12. The process of claim 10, further comprising removing said refractory core assembly after said molten material has solidified so as to from a slot in a wall of a portion of said turbine engine component.

13. The process of claim 12, wherein said removing step comprises removing said refractory core assembly using an acid leach operation.

14. The process of claim 10, wherein said placing step comprises placing a plurality of refractory core assemblies in said die.

15. The process of claim 10, wherein said placing step comprises placing said refractory core assembly in a portion of said die to be used to form at least one of an outer shroud ring and an inner shroud ring.

16. The process of claim 10, wherein said molten material pouring step comprises pouring a nickel based superalloy.

17. The process of claim 10, further comprising removing said turbine engine component with said airfoils from said ceramic shell mold.