MATERIAL REMOVAL METHOD

• US 20140223737A1
• Filed: 01/16/2014
• Published: 08/14/2014
• Est. Priority Date: 02/12/2013
• Status: Active Grant

• Current Assignee: Rolls-Royce PLC (Rolls-Royce Holdings Plc)
• Original Assignee: Rolls-Royce PLC (Rolls-Royce Holdings Plc)
• Inventors: KELL, James, AXINTE, Dragos, DAVIES, Samantha Helen, DAINE, Mark
• Granted Patent: US 9,409,262 B2
• Time in Patent Office: Days
• US Class Current: 29/889.1
• CPC Class Codes: B23K 2101/001 Turbines
• CPC Class Codes: B23K 2103/50 Inorganic material, e.g. metals, not provided for in B23K2103/02 – B23K2103/26
• CPC Class Codes: B23K 26/0622 by shaping pulses
• CPC Class Codes: B23K 26/361 for deburring or mechanical trimming B23K26/351 takes precedence
• CPC Class Codes: B23K 26/362 Laser etching
• CPC Class Codes: B23K 26/40 taking account of the properties of the material involved
• CPC Class Codes: B23P 6/002 Repairing turbine components, e.g. moving or stationary blades, rotors, B23P6/045 takes precedence
• CPC Class Codes: F01D 5/005 Repairing methods or devices
• CPC Class Codes: F05D 2230/13 using lasers
• CPC Class Codes: F05D 2230/80 Repairing, retrofitting or upgrading methods
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft
• CPC Class Codes: Y10T 29/49318 Repairing or disassembling

Abstract

A repair method for repairing a component (6a) of a gas turbine engine (10). The method comprises first and second steps. The first step comprises directing an energy beam toward the component (6a) to ablate a first region (54) of material to form a gap extending through the component (6a) between a repair region (58) a base region (58) of the component, wherein subsequent to the first step the repair region (58) and base region (56) are joined by a connecting portion (60). In the second step, an energy beam is direct toward the component (6a) to ablate the repair region (58) to remove the repair region (58) from the component (6a).

Claims

1. A material removal method comprising:

in a first step, directing an energy beam toward a component to ablate a first region of material to form a gap extending through the component between a repair region and a base region of the component, wherein subsequent to the first step, the repair region and base region are joined by a connecting portion; and

in a second step, directing an energy beam toward the component to ablate the repair region to remove the repair region from the component.

2. A method according to claim 1, wherein the gap has a sufficient width to provide a heat barrier between the repair region and the base region during the second step such that substantially no heat affected zone is formed in the base region by the ablation of the repair region.

3. A method according to claim 2, wherein the gap has a width of between 0.1 mm and 1 mm.

4. A method according to claim 3, wherein the gap has a width of approximately 0.5 mm.

5. A method according to claim 1, wherein the connecting portion has a width sufficient to provide a structural connection between the base region and the repair region such that substantially no material from the repair region is dislodged during the second step.

6. A method according to claim 5, wherein the connecting portion has a width of less than 1 mm, and may have a width of between 0.5 and 0.1 mm, and may have a width of substantially 0.5 mm.

7. A method according to claim 1, wherein the first step is carried out using first beam parameters such that substantially no heat affected zone is formed in the first region.

8. A method according to claim 1, wherein the second step is carried out using second beam parameters.

9. A method according to claim 7, wherein the beam parameters comprise any of incident energy density, beam fluence, beam power, scan speed, pulse repetition frequency, electromagnetic beam wavelength and incident beam diameter.

10. A method according to claim 9, wherein the first beam parameters comprise one or more of a relatively low power, a relatively fast scan speed, a relatively high pulse repetition frequency, and a relatively large beam diameter, and the second beam parameters comprise one or more of a relatively high power, a relatively slow scan speed, a relatively low pulse repetition frequency, and a relatively small beam diameter.

11. A method according to claim 1 further comprising a third step carried out subsequent to the second step, comprising ablating an edge of the base region.

12. A method according to claim 11, wherein the third step further comprises removing the connecting portion.

13. A method according to claim 1 wherein the energy beam is provided by a pulsed laser beam.

14. A method according to claim 1 wherein the method is applied to a component of a gas turbine engine.

15. A component repaired by the repair method according to claim 1.

16. A gas turbine engine comprising a component according to claim 15.