Fan case liner removal with external heat mat

Patent metadata

Field	Value
Publication number	US-10030540-B2
Application number	US-201514949247-A
Country	US
Kind code	B2
Filing date	Nov 23, 2015
Priority date	Nov 25, 2014
Publication date	Jul 24, 2018
Grant date	Jul 24, 2018

Abstract

A method of replacing a fan case liner panel in an engine fan case is provided. In one illustrative form, the method may include applying heat to an engine fan case to debond an adhesive layer, removing the first fan case liner panel, and bonding a second fan case liner panel.

First claim

What is claimed is:

1. A method of replacing a fan case liner in a fan case, the method comprising
applying heat to a portion of an exterior surface of a fan case to soften an adhesive layer bonding a first fan case liner panel to an inner surface of the fan case,
removing the first fan case liner panel and adhesive residue from the fan case to produce an undisrupted inner surface of the fan case, and
bonding a second fan case liner panel to the undisrupted inner surface of the fan case, wherein
applying heat to the portion of the exterior of the fan case is performed on the portion of the fan case containing the first fan case liner panel.

2. The method of claim 1 , wherein applying heat to the portion of the exterior of the fan case includes arranging a heating element along the exterior surface of the fan case and providing electricity to the heating element to heat the adhesive layer to a debonding temperature.

3. The method of claim 2 , wherein the heating element comprises a flexible silicon heating mat.

4. The method of claim 2 , wherein the portion of the exterior surface of the fan case overlies the first fan case liner panel.

5. The method of claim 2 , wherein the debonding temperature is about 150° C. to about 160° C.

6. The method of claim 5 , wherein the fan case is held at the debonding temperature for about five minutes to about one hour.

7. The method of claim 1 , wherein removing the first fan case liner panel includes prying the first fan case liner panel from the fan case.

8. The method of claim 7 , wherein removing the adhesive residue includes applying a solvent and manually removing the adhesive residue.

9. The method of claim 8 , wherein manually removing the adhesive residue from the inner surface of the fan case is performed with a scraper.

10. The method of claim 1 , wherein bonding the second fan case liner panel includes applying an unbonded adhesive layer to the undisrupted inner surface of the fan case and bonding the second fan case liner panel to the unbonded adhesive layer and the undisrupted inner surface.

11. The method of claim 10 , further including heating the exterior surface of the fan case to bond the second fan case liner panel to the fan case.

12. The method of claim 1 , further including removing edge fillers prior to applying heat to the exterior surface of the fan case.

13. The method of claim 1 , wherein the first fan case liner panel includes a bonding layer, a surface layer, and a core layer arranged to extend between and interconnect the bonding layer and the surface layer.

14. The method of claim 13 , wherein the adhesive layer is located between the bonding layer of the first fan case liner panel and the inner surface of the fan case.

15. The method of claim 14 , wherein the adhesive layer comprises a polysulphide adhesive.

16. The method of claim 14 , wherein the adhesive layer comprises a polythioether adhesive.

17. The method of claim 13 , wherein the fan case includes a plurality of fan case liner panels arranged in a ring along the inner surface of the fan case to circumferentially surround a fan included in a gas turbine engine.

18. A method of replacing a fan case liner in a fan case, the method comprising
applying heat to an exterior surface of a fan case to soften an adhesive bonding a first fan case liner panel to an inner surface of the fan case,
removing the first fan case liner panel and adhesive residue from the fan case to produce an undisrupted surface of the fan case, and
bonding a second fan case liner panel to the undisrupted surface of the fan case,
wherein, applying heat to the exterior of the fan case is performed on a portion of the fan case containing the first fan case liner panel, the first fan case liner panel includes a bonding layer, a surface layer, a core layer arranged to extend between and interconnect the bonding layer and the surface layer, and an adhesive layer located between the bonding layer of the first fan case liner panel and the inner surface of the fan case.

19. A replaceable fan case liner system for a turbine engine comprising,
a ring-shaped fan case arranged to circumferentially surround a fan,
a heat source arranged to extend along an exterior surface of the ring-shaped fan case, and
a fan case liner system configured to extend around an inner surface of the ring-shaped fan case between the fan and the ring-shaped fan case,
wherein the fan case liner system includes a fan case liner panel coupled to the ring-shaped fan case that forms a continuous ring on the inner surface of the ring-shaped fan case and the fan case liner panel is configured to bond to the inner surface of the ring-shaped fan case.

20. The fan case liner system of claim 19 , wherein the fan case liner system further includes an adhesive layer located between the fan case liner panel and the inner surface of the ring-shaped fan case.

Assignees

• Rolls Royce Nam Tech Inc
• Rolls Royce Corp
• Rolls Royce Plc
• Rolls Royce Nam Tech Inc

Inventors

• Molnar Daniel E
• Engebretsen Eric W
• Buckley Michael
• Thompson Ewan F

Classifications

• B29C63/0013 Primary

  Removing old coatings · CPC title

• F04D29/644

  especially adapted for elastic fluid pumps · CPC title

• F04D29/526

  Details of the casing section radially opposing blade tips (ducts F04D29/545) · CPC title

• F01D25/24 Primary

  Casings (modified for heating or cooling F01D25/14); Casing parts, e.g. diaphragms, casing fastenings (casings for rotary machines or engines in general F16M {; special arrangements in stators dealing with breaking-off of part of rotor F01D21/045}) · CPC title