Method of forming a cooling hole by laser drilling

• US 9,696,035 B2
• Filed: 05/01/2013
• Issued: 07/04/2017
• Est. Priority Date: 10/29/2010
• Status: Active Grant

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Starkweather, John Howard, Bennett, William, Gibbons, John, Urbanski, Anthony
• Primary Examiner(s): Evans, Geoffrey S
• Application Number:
  US13/875,150
• Publication Number:
  US 20130269354A1
• Time in Patent Office: 1,525 Days
• CPC Class Codes: B23K 26/0622 by shaping pulses
• CPC Class Codes: B23K 26/384 of specially shaped holes
• CPC Class Codes: B23K 26/388 Trepanning, i.e. boring by moving the beam spot about an axis
• CPC Class Codes: B23K 26/389 of fluid openings, e.g. nozzles, jets laser machining of inkjet nozzles B41J2/1634
• CPC Class Codes: B23K 26/55 for creating voids inside the workpiece, e.g. for forming flow passages or flow patterns
• CPC Class Codes: F23M 5/08 Cooling thereof; Tube walls
• CPC Class Codes: F23R 2900/00018 Manufacturing combustion chamber liners or subparts
• CPC Class Codes: F23R 2900/03041 Effusion cooled combustion chamber walls or domes
• CPC Class Codes: F23R 3/002 Wall structures F23R3/02 and F23R3/007 take precedence
• CPC Class Codes: F23R 3/04 Air inlet arrangements
• CPC Class Codes: F23R 3/06 Arrangement of apertures along the flame tube
• CPC Class Codes: Y02T 50/60 Efficient propulsion technologies, e.g. for aircraft

Abstract

A method for making shaped cooling holes in a substrate by pulsing and stopping a laser while moving the laser or substrate. The method produces shaped cooling holes with a bore angled relative to an exit surface of the combustor liner. One end of the bore is an inlet formed in an inlet surface of the combustor liner. The other end of the bore is an outlet formed in the exit surface of the combustor liner. The outlet has a shaped portion that expands in only one dimension.

Claims

1. A method of forming a cooling aperture, comprises:

drilling a center bore at a preselected angle from an exit surface toward an inlet surface through a substrate;

pulsing a laser, a first series while moving one of said laser and said substrate in a first direction relative to a center line of said bore;

stopping said pulsing said laser said first series and moving said one of said laser and said substrate;

pulsing said laser and second series while moving said one of said laser and said substrate in a second direction relative to said center line of said bore;

stopping said pulsing said laser said second series and moving said one of said laser and said substrate;

trepanning said laser to form a substantially oval shaped inlet.

2. The method of forming a cooling aperture of claim 1, forming an oval shaped outlet with a larger area than said substantially oval shaped inlet.

3. The method of forming a cooling aperture of claim 1, forming a transition point in said bore.