Blind fasteners with EME protection and sealing

Patent metadata

Field	Value
Publication number	US-12454975-B2
Application number	US-202318182324-A
Country	US
Kind code	B2
Filing date	Mar 11, 2023
Priority date	Mar 11, 2023
Publication date	Oct 28, 2025
Grant date	Oct 28, 2025

Abstract

Methods and blind fasteners with EME protection are provided. A blind fastener comprises a shank having a bulb forming portion; a head; and an electromagnetic effects (EME) protection sealant positioned on at least one of the bulb forming portion of the shank or under the head.

First claim

What is claimed is:

1. A blind fastener that comprises:
a sleeve that comprises a bulb forming portion and a head; and
an electromagnetic effects (EME) protection sealant positioned on at least one of the bulb forming portion of the sleeve or under the head.

2. The blind fastener of claim 1 , wherein the electromagnetic effects (EME) protection sealant comprises a malleable alloy.

3. The blind fastener of claim 1 , wherein the electromagnetic effects (EME) protection sealant comprises an insulating epoxy.

4. The blind fastener of claim 3 , wherein the insulating epoxy comprises a rubber.

5. The blind fastener of claim 1 , wherein the electromagnetic effects (EME) protection sealant comprises a two-part epoxy.

6. The blind fastener of claim 1 , wherein the electromagnetic effects (EME) protection sealant is heat activated.

7. The blind fastener of claim 1 , wherein the electromagnetic effects (EME) protection sealant is non-conductive.

8. The blind fastener of claim 1 , wherein the electromagnetic effects (EME) protection sealant is a film.

9. The blind fastener of claim 1 , wherein the electromagnetic effects (EME) protection sealant is configured to seal against aircraft fuel.

10. A method of providing electromagnetic effects protection to a composite structure, the method comprising:
applying an electromagnetic effects (EME) protection sealant on at least one of a bulb forming portion of a sleeve or under a head of a blind fastener; and
installing the blind fastener with the electromagnetic effects (EME) protection sealant into the composite structure such that the electromagnetic effects (EME) protection sealant is between the blind fastener and the composite structure.

11. The method of claim 10 , further comprising applying the electromagnetic effects (EME) protection sealant the bulb forming portion of the sleeve and under the head of the blind fastener.

12. The method of claim 10 , wherein installing the blind fastener forms a bulb against the composite structure.

13. The method of claim 10 , wherein installing the blind fastener comprises forming a bulb against an inner mold line of a hole of the composite structure.

14. The method of claim 10 , wherein installing the blind fastener presses the electromagnetic effects (EME) protection sealant between the blind fastener and the composite structure.

15. The method of claim 10 , wherein applying the electromagnetic effects (EME) protection sealant comprises applying the electromagnetic effects (EME) protection sealant as a film.

16. The method of claim 10 , wherein applying the electromagnetic effects (EME) protection sealant comprises brushing on the electromagnetic effects (EME) protection sealant.

17. The method of claim 10 , wherein applying the electromagnetic effects (EME) protection sealant comprises spraying on the electromagnetic effects (EME) protection sealant.

18. The method of claim 10 , wherein installing the blind fastener comprises activating the electromagnetic effects (EME) protection sealant with heat.

19. The method of claim 18 , wherein activating the electromagnetic effects (EME) protection sealant with heat comprises activating the electromagnetic effects (EME) protection sealant with friction generated heat from friction between the blind fastener and the composite structure.

20. The method of claim 10 , wherein applying an electromagnetic effects (EME) protection sealant to a number of portions of the blind fastener comprises applying the electromagnetic effects (EME) protection sealant to a fay surface of the blind fastener.

21. A composite structure that comprises:
a first composite component;
a second composite component;
a blind fastener installed through a hole in the first composite component and the second composite component; and
an electromagnetic effects (EME) protection sealant positioned at least one of between a bulb of the blind fastener and the second composite component or between a head of the blind fastener and the first composite component.

22. The composite structure of claim 21 , wherein the electromagnetic effects (EME) protection sealant forms a fluid tight seal between at least one of the first composite component or the second composite component and the blind fastener.

23. The composite structure of claim 21 , wherein a remainder of a shank of the blind fastener is free of the electromagnetic effects (EME) protection sealant.

24. A method of forming a liquid-tight seal during blind fastener installation comprising:
inserting a blind fastener with electromagnetic effects (EME) protection sealant on at least one of a bulb forming portion of a sleeve or under a head of the blind fastener through a hole of a composite structure; and
installing the blind fastener such that the electromagnetic effects (EME) protection sealant is secured between the blind fastener and the composite structure to seal at least one side of the hole of the composite structure.

25. A method of forming an alloy seal during blind fastener installation comprising:
locating a malleable alloy between a number of portions of a blind fastener and a composite structure; and
friction forming the malleable alloy into a seal placed on at least one of a bulb forming portion of a sleeve or under a head of the blind fastener during blind fastener installation wherein friction forming the malleable alloy into a seal comprises forming an electromagnetic effects (EME) protection seal.

Assignees

• Boeing Co

Inventors

• Simpson Blake
• Morden Sean Dennis

Classifications

• F16B19/1054 Primary

  the pull-mandrel or the like being frangible · CPC title

• F16B2019/045

  Coated rivets · CPC title

• F16B19/008 Primary

  with sealing means · CPC title