MANUFACTURING METHODS FOR MULTI-LOBED COOLING HOLES

• US 20130206739A1
• Filed: 07/09/2012
• Published: 08/15/2013
• Est. Priority Date: 02/15/2012
• Status: Active Grant

• Current Assignee: Rtx Corporation
• Original Assignee: United Technologies Corporation (Rtx Corporation)
• Inventors: Reed, Gordon Miller, Faughnan, Paul R. Jr., Quitter, John
• Granted Patent: US 9,598,979 B2
• Time in Patent Office: Days
• US Class Current: 219/121.71
• CPC Class Codes: B23B 35/00 Methods for boring or drilling, or for working essentially requiring the use of boring or drilling machines; Use of auxiliary equipment in connection with such methods
• CPC Class Codes: B23C 3/00 Milling particular work; Special milling operations; Machines therefor milling gear-teeth B23F, heat assisted machining B23P25/00
• CPC Class Codes: B23K 2101/001 Turbines
• CPC Class Codes: B23K 26/0622 by shaping pulses
• CPC Class Codes: B23K 26/082 Scanning systems, i.e. devices involving movement of the laser beam relative to the laser head
• CPC Class Codes: B23K 26/146 the fluid stream containing a liquid
• CPC Class Codes: B23K 26/389 of fluid openings, e.g. nozzles, jets laser machining of inkjet nozzles B41J2/1634
• CPC Class Codes: B23P 15/04 turbine or like blades from several pieces
• CPC Class Codes: B23P 2700/06 Cooling passages of turbine components, e.g. unblocking or preventing blocking of cooling passages of turbine components
• CPC Class Codes: B26F 3/004 by means of a fluid jet methods for use of abrasive blasting for cutting B24C1/045; guns for abrasive fluid jets B24C5/02; perforating by non-mechanical means, e.g. by fluid jet B26F1/26
• CPC Class Codes: F01D 25/12 Cooling
• CPC Class Codes: F01D 5/186 Film cooling F01D5/187 takes precedence
• CPC Class Codes: F01D 9/065 Fluid supply or removal conduits traversing the working fluid flow, e.g. for lubrication-, cooling-, or sealing fluids see also F01D25/16, F01D25/24 and F01D25/26
• CPC Class Codes: F05D 2240/81 Cooled platforms
• CPC Class Codes: F05D 2260/202 by film cooling
• CPC Class Codes: F23R 2900/00019 Repairing or maintaining combustion chamber liners or subparts
• CPC Class Codes: F23R 2900/03042 Film cooled combustion chamber walls or domes
• CPC Class Codes: F23R 3/002 Wall structures F23R3/02 and F23R3/007 take precedence
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

A method for producing a diffusion cooling hole extending between a wall having a first wall surface and a second wall surface includes forming a cooling hole inlet at the first wall surface, forming a cooling hole outlet at the second wall surface, forming a metering section downstream from the inlet and forming a multi-lobed diffusing section between the metering section and the outlet. The inlet, outlet, metering section and multi-lobed diffusing section are formed by laser drilling, particle beam machining, fluid jet guided laser machining, mechanical machining, masking and combinations thereof.

Claims

1. A method for producing a diffusion cooling hole extending between a wall having a first wall surface and a second wall surface, the method comprising:

forming a cooling hole inlet at the first wall surface;

forming a cooling hole outlet at the second wall surface;

forming a metering section downstream from the inlet; and

forming a multi-lobed diffusing section between the metering section and the outlet,

wherein the inlet, outlet, metering section and multi-lobed diffusing section are formed by a technique selected from the group consisting of laser drilling, particle beam machining, fluid jet guided laser machining, mechanical machining, masking and combinations thereof.

2. The method of claim 1, wherein the wall comprises a metal or superalloy substrate.

3. The method of claim 1, wherein the second wall surface comprises a coating, and wherein at least a portion of the cooling hole extends through the coating.

4. The method of claim 3, wherein the coating comprises:

a bond coating; and

a thermal barrier coating.

5. The method of claim 4, wherein a portion of the diffusing section is located within the coating.

6. The method of claim 5, wherein the entire diffusing section is located within the coating.

7. The method of claim 6, wherein a portion of the metering section is located within the coating.

8. The method of claim 1, wherein the inlet and metering section are formed using a first laser having a frequency between about 5 Hz and about 200 kHz and a millisecond (10⁻

3) to nanosecond (10<sup>−

9</sup>) pulse duration range, and wherein the multi-lobed diffusing section and outlet are formed using a second laser having a frequency between about 1 kHz and about 200 kHz and a pulse duration range from nano (10<sup>−

9</sup>) to femto (10<sup>−

15</sup>) seconds.

9. The method of claim 8, wherein the wall comprises a coating on the second wall surface, and wherein at least a portion of the cooling hole extends through the coating.

10. The method of claim 1, wherein the inlet, metering section, multi-lobed diffusing section and outlet are formed using a fluid jet guided laser.

11. The method of claim 10, wherein the wall comprises a coating on the second wall surface, and wherein at least a portion of the cooling hole extends through the coating.

12. The method of claim 1, wherein the inlet, metering section, multi-lobed diffusing section and outlet are formed using a particle beam.

13. The method of claim 12, wherein the particle beam is an electron beam.

14. The method of claim 12, wherein the particle beam is an ion beam or molecular beam.

15. The method of claim 13, wherein the wall comprises a coating on the second wall surface, and wherein at least a portion of the cooling hole extends through the coating.

16. The method of claim 1, wherein the inlet, metering section, multi-lobed diffusing section and outlet are formed by a technique selected from the group consisting of drilling, milling, grinding, superabrasive machining and combinations thereof.

17. The method of claim 1, wherein the inlet and metering section are formed by drilling, and wherein the multi-lobed diffusing section and outlet are formed using a laser having a frequency between about 1 kHz and about 200 kHz and a pulse duration range from nano (10⁻

9) to femto (10<sup>−

15</sup>) seconds.

18. The method of claim 1, wherein the inlet and metering section are formed using a laser having a frequency between about 5 Hz and about 200 kHz, and a millisecond (10⁻

3) to nanosecond (10<sup>−

9</sup>) pulse duration range, and wherein the multi-lobed diffusing section and outlet are formed by a technique selected from the group consisting of drilling, milling, grinding, superabrasive machining and combinations thereof.

19. The method of claim 3, wherein the outlet and the portion of the diffusing section extending through the coating are formed by masking.

20. The method of claim 1, wherein the metering section and the diffusing section are formed using different techniques.

21. The method of claim 1, wherein the inlet and the metering section are formed before the diffusing section and the outlet.

22. The method of claim 1, wherein the inlet and the metering section are formed after the diffusing section and the outlet.

23. A method for producing a diffusion cooling hole extending between a wall having a first wall surface and a second wall surface, the method comprising:

forming a cooling hole inlet at the first wall surface;

forming a cooling hole outlet at the second wall surface;

forming a metering section downstream from the inlet; and

forming a multi-lobed diffusing section between the metering section and the outlet,

wherein the inlet and metering section are formed by a first technique selected from the group consisting of laser drilling, particle beam machining, fluid jet guided laser machining, mechanical machining and masking, and wherein the outlet and multi-lobed diffusing section are formed by a second technique different from the first technique and selected from the group consisting of laser drilling, particle beam drilling, fluid jet guided laser machining, mechanical machining and masking.

24. A method for repairing a component having a wall with multi-lobed diffusion cooling holes, the method comprising:

applying a new coating to the wall;

locating the diffusion cooling hole to be repaired;

forming a multi-lobed diffusing section and an outlet in the new coating to correspond with a metering section located in the wall, wherein the multi-lobed diffusing section and the outlet are formed by a technique selected from the group consisting of laser drilling, particle beam machining, fluid jet guided laser machining, mechanical machining, masking and combinations thereof.

25. The method of claim 24, further comprising:

removing an existing coating from the wall prior to applying the new coating.