Fastener system for a thermal protection system

• US 10,443,637 B2
• Filed: 09/12/2017
• Issued: 10/15/2019
• Est. Priority Date: 09/12/2017
• Status: Active Grant

• Current Assignee: ADP LLC (Automatic Data Processing Incorporated), The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Pinney, Thomas Richardson
• Primary Examiner(s): Thomas, Alexander S
• Application Number:
  US15/702,425
• Publication Number:
  US 20190078599A1
• Time in Patent Office: 763 Days
• CPC Class Codes: B64G 1/58 Thermal protection, e.g. heat shields
• CPC Class Codes: F02C 7/24 Heat or noise insulation air intakes having provisions for noise suppression F02C7/045; turbine exhaust heads, chambers, or the like F01D25/30; silencing nozzles of jet-propulsion plants F02K1/00
• CPC Class Codes: F02K 1/822 Heat insulating structures or liners, cooling arrangements, e.g. post combustion liners; Infrared radiation suppressors
• CPC Class Codes: F05D 2260/231 Preventing heat transfer
• CPC Class Codes: F16B 33/006 Non-metallic fasteners using screw-thread
• CPC Class Codes: F16B 35/06 Specially-shaped heads special shape in order to rotate the bolt F16B23/00 ; separate hook adaptors for bolts F16B43/025
• CPC Class Codes: F16B 5/02 by means of fastening members using screw-thread F16B5/0004 takes precedence; construction of screw-threaded connections F16B25/00 - F16B39/00
• CPC Class Codes: F16B 5/0241 with the possibility for the connection to absorb deformation, e.g. thermal or vibrational
• CPC Class Codes: Y10T 428/233 Foamed or expanded material encased
• CPC Class Codes: Y10T 428/24008 including fastener for attaching to external surface
• CPC Class Codes: Y10T 428/24322 Composite web or sheet
• CPC Class Codes: Y10T 428/249923 Including interlaminar mechanical fastener

Abstract

A thermal protection system comprises a ceramic panel, a plurality of apertures, and a fastener system within each of the plurality of apertures. The ceramic panel has a plurality of attachment points to a structure. The plurality of apertures extends through the ceramic panel, each aperture of the plurality of apertures located at an attachment point of the plurality of attachment points. Each fastener system comprises a fastener having a head with a spherical underside and a ceramic bushing with a mating surface configured to mate with the spherical underside of the head of the fastener.

Claims

1. A thermal protection system comprising:

a ceramic panel having a plurality of attachment points to a structure, wherein the ceramic panel comprises a number of ceramic matrix composite facesheets and a ceramic foam panel;

a plurality of apertures extending through the ceramic panel, each aperture of the plurality of apertures located at an attachment point of the plurality of attachment points; and

a fastener system within each of the plurality of apertures, wherein each fastener system comprises;

a fastener having a head with a spherical underside; and

a ceramic bushing with a mating surface configured to mate with the spherical underside of the head of the fastener.

2. The thermal protection system of claim 1, wherein the number of ceramic matrix composite facesheets comprises a ceramic matrix composite facesheet contacting a first face of the ceramic foam panel.

3. The thermal protection system of claim 2, wherein the number of ceramic matrix composite facesheets further comprises a second ceramic matrix composite facesheet contacting a second face of the ceramic foam panel, wherein the second face is opposite the first face.

4. The thermal protection system of claim 1, wherein the number of ceramic matrix composite facesheets comprises a ceramic matrix composite facesheet wrapped around the ceramic foam panel.

5. The thermal protection system of claim 1, wherein each aperture of the plurality of apertures comprises a counterbore, and wherein each ceramic bushing is within a respective counterbore.

6. The thermal protection system of claim 5, wherein each counterbore extends through the ceramic foam panel.

7. The thermal protection system of claim 5, wherein each counterbore extends through only a portion the ceramic foam panel.

8. The thermal protection system of claim 1, wherein each fastener system further comprises a ceramic cover plug having an outer diameter equal to an outer diameter of the ceramic bushing.

9. The thermal protection system of claim 1, wherein each fastener is formed of a ceramic material.

10. A thermal protection system comprising:

a ceramic panel having a plurality of attachment points to a structure;

a plurality of apertures extending through the ceramic panel, each aperture of the plurality of apertures located at an attachment point of the plurality of attachment points; and

a fastener system within each of the plurality of apertures, wherein each fastener system comprises;

a fastener having a head with a spherical underside; and

a ceramic bushing with a mating surface configured to mate with the spherical underside of the head of the fastener;

wherein each fastener system further comprises a nut secured to a shaft of a respective fastener, and further comprising;

a non-structural layer between each nut and the ceramic panel, wherein the non-structural layer is one of a compliant material layer or a gap.

11. A method comprising:

forming an aperture extending through a ceramic panel of a thermal protection system₁ wherein the ceramic panel comprises a ceramic matrix composite facesheet wrapped around a ceramic foam panel, and wherein forming the aperture comprises forming a counterbore extending through the ceramic foam panel;

inserting a ceramic bushing with a mating surface into the aperture; and

inserting a fastener having a head with a spherical underside into the aperture such that the spherical underside of the head of the fastener mates with the mating surface of the ceramic bushing.

12. The method of claim 11 further comprising:

bonding the ceramic bushing within the counterbore of the aperture.

13. The method of claim 11, further comprising:

operating a platform comprising the thermal protection system; and

allowing movement of the ceramic panel during operation by sliding the mating surface relative to the spherical underside of the head of the fastener.

14. The method of claim 11, further comprising:

inserting a ceramic cover plug into the aperture.

15. A method comprising:

forming an aperture extending through a ceramic panel of a thermal protection system, wherein the ceramic panel comprises a ceramic matrix composite facesheet wrapped around a ceramic foam panel, and wherein forming the aperture comprises forming a counterbore extending through only a portion the ceramic foam panel;

inserting a ceramic bushing with a mating surface into the aperture; and

inserting a fastener having a head with a spherical underside into the aperture such that the spherical underside of the head of the fastener mates with the mating surface of the ceramic bushing.

16. The method of claim 15 further comprising:

bonding the ceramic bushing within the counterbore of the aperture.

17. The method of claim 15, further comprising:

operating a platform comprising the thermal protection system; and

allowing movement of the ceramic panel during operation by sliding the mating surface relative to the spherical underside of the head of the fastener.

18. The method of claim 15, further comprising:

inserting a ceramic cover plug into the aperture.

19. A method comprising:

forming an aperture extending through a ceramic panel of a thermal protection system;

inserting a ceramic bushing with a mating surface into the aperture;

inserting a fastener having a head with a spherical underside into the aperture such that the spherical underside of the head of the fastener mates with the mating surface of the ceramic bushing;

extending a shaft of the fastener through a non-structural layer; and

attaching a nut to the shaft such that the non-structural layer is positioned between the nut and the ceramic panel, wherein the non-structural layer is one of a compliant material layer or a gap.

20. The method of claim 19 further comprising:

bonding the ceramic bushing within a counterbore of the aperture.

21. The method of claim 19, further comprising:

operating a platform comprising the thermal protection system; and

allowing movement of the ceramic panel during operation by sliding the mating surface relative to the spherical underside of the head of the fastener.

22. The method of claim 19, further comprising:

inserting a ceramic cover plug into the aperture.