SYSTEMS AND METHODS FOR DEEP TIP CRACK REPAIR

• US 20170167263A1
• Filed: 12/10/2015
• Published: 06/15/2017
• Est. Priority Date: 12/10/2015
• Status: Active Grant

• Current Assignee: GE Infrastructure Technology, LLC (GE Vernova, Inc.)
• Original Assignee: General Electric Company
• Inventors: WHIMS, LAWRENCE JAMES, CONNOR, JAMES RYAN, DORRIETY, DANIEL JAMES, KRETSCHMAR, ANDREA BOOHER, COOK, PAUL A., HENDERSON, BRIAN LESLIE
• Granted Patent: US 10,174,617 B2
• Time in Patent Office: Days
• CPC Class Codes: B23K 1/0018 Brazing of turbine parts
• CPC Class Codes: B23K 1/19 taking account of the properties of the materials to be soldered
• CPC Class Codes: B23K 1/20 Preliminary treatment of work or areas to be soldered, e.g. in respect of a galvanic coating preparation of surfaces in particular ways, see the relevant classes for the treatments or the materials treated, e.g. C04B, C23C
• CPC Class Codes: B23K 2101/001 Turbines
• CPC Class Codes: B23K 35/0222 for use in soldering, brazing B23K35/0205 takes precedence
• CPC Class Codes: B23K 35/0244 Powders, particles or spheres; Preforms made therefrom
• CPC Class Codes: B23K 35/025 Pastes, creams, slurries
• CPC Class Codes: B23K 35/0255 for use in welding B23K35/0205 takes precedence
• CPC Class Codes: B23K 35/30 with the principal constituent melting at less than 1550 degrees C
• CPC Class Codes: B23K 35/3033 Ni as the principal constituent
• CPC Class Codes: B23K 35/3046 Co as the principal constituent
• CPC Class Codes: B23K 35/3053 Fe as the principal constituent
• CPC Class Codes: B23P 6/002 Repairing turbine components, e.g. moving or stationary blades, rotors, B23P6/045 takes precedence
• CPC Class Codes: B23P 6/007 using only additive methods, e.g. build-up welding
• CPC Class Codes: B33Y 10/00 Processes of additive manufacturing
• CPC Class Codes: B33Y 80/00 Products made by additive manufacturing
• CPC Class Codes: F01D 5/005 Repairing methods or devices
• CPC Class Codes: F01D 5/147 Construction, i.e. structural features, e.g. of weight-saving hollow blades F01D5/148, F01D5/16 and F01D5/20 take precedence; blade shape F01D5/141; blades with cooling or heating channels or cavities F01D5/18; heating, heat-insulating or cooling means on blades F01D5/18
• CPC Class Codes: F01D 5/20 Specially-shaped blade tips to seal space between tips and stator F01D5/225 takes precedence
• CPC Class Codes: F05D 2220/32 in gas turbines
• CPC Class Codes: F05D 2230/10 : by removing material
• CPC Class Codes: F05D 2230/237 : Brazing
• CPC Class Codes: F05D 2230/80 : Repairing, retrofitting or upgrading methods
• CPC Class Codes: F05D 2240/307 : related to the tip of a rotor blade
• CPC Class Codes: F05D 2300/175 : Superalloys

Abstract

The present application provides a method of repairing a turbine blade. The method may include the steps of removing an existing tip cap from the turbine blade in whole or in part, machining the turbine blade to form a machined groove, positioning an insert in the machined groove, welding the insert to the turbine blade, and brazing the turbine blade.

Claims

1. A method of repairing a turbine blade, comprising:

removing an existing tip cap from the turbine blade in whole or in part;

machining the turbine blade to form a machined groove;

positioning an insert in the machined groove;

welding the insert to the turbine blade; and

brazing the turbine blade.

2. The method of claim 1, wherein the step of removing an existing tip cap comprises machining the tip cap.

3. The method of claim 1, further comprising the step of replacing the tip cap on the turbine blade.

4. The method of claim 1, further comprising the step of forming the insert.

5. The method of claim 4, wherein the step of forming the insert comprises forming the insert from a pre-sintered preform material.

6. The method of claim 4, wherein the step of forming the insert comprises forming the insert from a superalloy material.

7. The method of claim 4, wherein the step of forming the insert comprises forming the insert from a base material.

8. The method of claim 4, wherein the step of forming the insert comprises an additive manufacturing process.

9. The method of claim 1, wherein the step of machining the turbine blade comprises machining the turbine blade to remove a crack.

10. The method of claim 1, wherein the step of machining the turbine blade to form a machined groove comprises machining the machined groove to accommodate the insert.

11. The method of claim 1, wherein the step of machining the turbine blade to form a machined groove comprises machining the machined groove to accommodate the insert and a welding alloy.

12. The method of claim 1, wherein the step of welding the insert to the turbine blade comprises a welding alloy on top of the insert.

13. The method of claim 1, wherein the step of brazing the turbine blade comprises brazing a brazeable paste thereon.

14. The method of claim 1, wherein the turbine blade comprises a stage one bucket.

15. A turbine blade for use in a gas turbine engine, comprising:

an airfoil;

a tip cap at the end of the airfoil;

an insert welded to the airfoil about the tip cap; and

a brazeable paste brazed about the insert.

16. A method of repairing a turbine blade, comprising:

removing an existing tip cap from the turbine blade in whole or in part;

machining a crack in the turbine blade to form a machined groove;

positioning a pre-sintered preform insert in the machined groove;

welding the pre-sintered preform insert to the turbine blade; and

brazing the turbine blade.

17. The method of claim 16, wherein the step of removing an existing tip cap comprises machining the tip cap.

18. The method of claim 16, further comprising the step of replacing the tip cap on the turbine blade.

19. The method of claim 16, wherein the step of welding the insert to the turbine blade comprises a welding alloy on top of the insert.

20. The method of claim 16, wherein the step of brazing the turbine blade comprises brazing a brazeable paste.