Fan case bushing

• US 10,648,478 B2
• Filed: 06/24/2019
• Issued: 05/12/2020
• Est. Priority Date: 11/23/2015
• Status: Active Grant

• Current Assignee: Rtx Corporation
• Original Assignee: United Technologies Corporation (Raytheon Technologies Corporation d/b/a RTX)
• Inventors: Chow, Wai Tuck, Prihar, Ron I
• Primary Examiner(s): McMahon, Matthew R
• Application Number:
  US16/449,815
• Publication Number:
  US 20190309764A1
• Time in Patent Office: 323 Days
• CPC Class Codes: F01D 25/243 Flange connections; Bolting arrangements F01D25/265 takes precedence
• CPC Class Codes: F04D 19/002 Axial flow fans
• CPC Class Codes: F04D 29/056 Bearings
• CPC Class Codes: F04D 29/522 especially adapted for elastic fluid pumps
• CPC Class Codes: F04D 29/526 Details of the casing section radially opposing blade tips ducts F04D29/545
• CPC Class Codes: F04D 29/644 especially adapted for elastic fluid pumps
• CPC Class Codes: F05B 2230/60 Assembly methods
• CPC Class Codes: F05B 2260/301 Retaining bolts or nuts
• CPC Class Codes: F05D 2230/60 Assembly methods
• CPC Class Codes: F05D 2230/80 Repairing, retrofitting or upgrading methods
• CPC Class Codes: F05D 2260/31 Retaining bolts or nuts

Abstract

A bushing including a body portion including a cylinder portion having a bore there through configured to receive a bolt; a flange portion orthogonal and integral to the cylinder portion, the flange portion configured to abut a load bearing surface of a flange; a lip portion orthogonal to and integral to the flange portion proximate the cylinder portion, wherein the lip portion redistributes a flange load.

Claims

1. A method of redistributing a flange load for a repaired casing flange bolt hole comprising:

coupling a first casing flange with a second casing flange, wherein said first casing flange comprises at least one circular bolt hole, said second casing flange comprising at least one circular bolt hole aligned with said first casing flange bolt hole, wherein said second casing flange at least one bolt hole has a diameter larger than a diameter of said first casing flange at least one circular bolt hole;

coupling a bushing with said second casing flange at least one bolt hole, wherein said bushing comprising a body portion including a cylinder portion having a circular bore configured to receive a circular bolt inserted through said circular bore and said first casing flange at least one bolt hole, said cylinder portion having an outer diameter configured to insert into and abut the second casing flange at least one bolt hole;

a flange portion orthogonal and integral to said cylinder portion, said flange portion configured to couple with a load bearing surface of said second casing flange;

a lip portion integral to said flange portion proximate said cylinder portion, wherein said lip portion comprises a curvilinear shape that matches a radius of a fillet of said second casing flange; and

redistributing a flange load with said lip portion of said bushing.

2. The process of claim 1, further comprising:

bearing said flange load with said lip portion along a fillet region of said second casing flange.

3. The process of claim 1, further comprising:

varying a thickness of said lip portion extending along said lip portion proximate said fillet region.

4. The process of claim 1, wherein said lip portion and a thickness of said bushing varies responsive to at least one of a diameter of a bolt and a diameter of said second casing flange bolt hole.

5. The process of claim 1, further comprising:

reducing the thickness of said bushing to retain a flange bolt length equal to a flange bolt length prior to said flange repair.

6. The process of claim 5, wherein said reducing step includes providing a reducing portion located in said bushing at an outer face proximate the circular bore of said bushing.