Pipe installation

Patent metadata

Field	Value
Publication number	US-10293952-B2
Application number	US-201615259901-A
Country	US
Kind code	B2
Filing date	Sep 8, 2016
Priority date	Sep 8, 2015
Publication date	May 21, 2019
Grant date	May 21, 2019

Abstract

A pipe installation including conductive first and second pipes installed in a fuel tank; and a fitting which connects the first and second pipes and enables fluid to flow through the pipes via a conduit in the fitting. The fitting is attached to the first or second pipe by a flexible joint which permits relative movement between the fitting and the first or second pipe. The fitting is attached to a structure of the fuel tank. The fitting provides a path of least electrical resistance between the first or second pipe and the structure, and the path of least electrical resistance has a resistance between 50Ω and 100MΩ.

First claim

The invention is:

1. A pipe installation comprising:
conductive first and second pipes installed in a fuel tank; and
a fitting which connects the first and second pipes and enables fluid to flow through the pipes via a conduit in the fitting,
wherein the fitting is attached to the first or second pipe by a flexible joint which permits relative movement between the fitting and the first or second pipe,
the fitting is attached to a structure of the fuel tank,
the fitting provides a path of least electrical resistance between the first or second pipe and the structure, and
the path of least electrical resistance through the fitting and to the structure has a resistance between 50Ω and 100 MΩ.

2. The pipe installation of claim 1 wherein the fitting comprises a body containing the conduit, and a flange extending from the body, wherein the fitting is attached to the structure of the fuel tank by the flange.

3. The pipe installation of claim 2 wherein the body and the flange are formed from a polymer mixed with conductive filler particles, and the body and a flange have a resistance between 50Ω and 100 MΩ.

4. The pipe installation of claim 2 wherein the fitting further comprises a resistive element between the flange and the structure, a portion of the path of least electrical resistance passes between the flange and the structure through the resistive element, and the portion of the path of least electrical resistance has a resistance between 50Ω and 100 MΩ.

5. The pipe installation of claim 4 wherein the body and the flange are metallic.

6. The pipe installation of claim 2 wherein the flange is attached to the structure by fasteners which pass through holes in the flange, and the fasteners are electrically isolated from the structure and the flange.

7. The pipe installation of claim 4 wherein the flange is attached to the structure by fasteners which pass through holes in the flange, and each fastener comprises a metallic body, and an electrically insulating barrier between the metallic body and the flange which electrically isolates the metallic body from the flange and the structure.

8. The pipe installation of claim 1 wherein the path of least electrical resistance has a resistance greater than 1 kΩ.

9. The pipe installation of claim 1 wherein the path of least electrical resistance has a resistance less than 10 MΩ.

10. The pipe installation of claim 1 wherein the conduit in the fitting has an axis, and the flexible joint permits an axial relative movement between the fitting and the first or second pipe in an axial direction parallel with the axis; or
the flexible joint permits a pivoting relative movement between the fitting and the first or second pipe in which an axis of the first or second pipe pivots relative to the fitting.

11. The pipe installation of claim 10 wherein the axial relative movement has a permitted range greater than 1 mm; or
the pivoting relative movement has a permitted range greater than 1 degree.

12. The pipe installation of claim 1 wherein the fitting is a single piece component and includes a first socket which receives the first pipe, and a second socket which receives the second pipe.

13. The pipe installation of claim 1 wherein the flexible joint includes a first flexible joint which permits relative movement between the fitting and the first pipe, and a second flexible joint which permits relative movement between the fitting and the second pipe.

14. The pipe installation of claim 1 wherein the fuel tank is an aircraft fuel tank.

15. The pipe installation of claim 1 wherein the first and second pipes are liquid fuel pipes, and the fitting enables liquid fuel to flow through the pipes via the conduit in the fitting.

16. The pipe installation of claim 1 wherein the first and second pipes have outer diameters which are greater than 15 mm.

17. The pipe installation of claim 1 wherein each for the first and second pipes is connected to the fitting by a respective metallic bonding lead.

18. The pipe installation of claim 1 wherein the conductive first and second pipes are metallic.

19. The pipe installation of claim 1 wherein the conductive first and second pipes are metallic along their full length.

20. The pipe installation of claim 1 , wherein the fuel tank has at least one fuel tank wall formed from a composite material.

21. An aircraft wing comprising the pipe installation of claim 1 .

22. A fuel tank assembly comprising:
a fuel tank in a vehicle;
first and second conductive pipes in the fuel tank;
a fitting attached to a structure of the fuel tank and coupling the first and second conductive pipes, wherein a fluid flow path extends through the first and second conductive pipes and a passage in the fitting; and
a flexible joint between the fitting and at least one of the first and second conductive pipes, wherein the flexible joint is configured to enable relative movement between the fitting and the at least one of the first and second conductive pipes;
wherein the fitting is in a path of least electrical resistance between the structure of the fuel tank and at least one of the first and second conductive pipes, wherein a portion of the path of least electrical resistance through the fitting and to the structure has an electrical resistance in a range of 50Ω to 100 MΩ.

23. The fuel tank assembly of claim 22 wherein the vehicle is an aircraft, the fuel tank is a fuel tank for a wing of the aircraft and the structure is a rib in the wing of the aircraft.

24. The fuel tank assembly of claim 22 wherein the fitting is a single piece fitting, and the single piece fitting includes a conduit defining the passage through the fitting and a flange extending outward from the conduit, wherein the flange has a flange surface configured to abut a fuel tank surface of the structure of the fuel tank, and the conduit includes a first open end configured to connect to an end of the first conductive pipe and a second open end configured to connect to an end of the second conductive pipe.

25. The fuel tank assembly of claim 24 further comprising a gasket between the flange surface and the fuel tank surface, wherein the gasket is in the path of least electrical resistance and the gasket is formed of a polymer with conductive filler particles.

26. The fuel tank assembly of claim 25 wherein the gasket includes an opening configured to receive the conduit, and at least one of surface of the opening in the gasket or a surface of the conduit adjacent the opening is coated with an insulating coating.

27. The fuel tank assembly of claim 22 wherein the fitting is formed of a polymer including conductive filler particles and the fitting has a resistance between 50Ω to 100 MΩ.

28. The fuel tank assembly of claim 22 wherein the fitting is a single piece fitting formed of a material having an electrical resistance in the range of 50Ω to 100 MΩ.

29. The fuel tank assembly of claim 22 further comprising a gasket sandwiched between the fitting and the structure of the fuel tank, wherein the gasket has an electrical resistance in the range of 50Ω to 100 MΩand the gasket is in the path of least electrical resistance.

30. The fuel tank assembly of claim 29 wherein the fitting is formed of a metallic conductive material.

31. A fuel tank assembly comprising:
a fuel tank in a

Assignees

• Airbus Operations Ltd

Inventors

• James Dylan
• Pout Alan

Classifications

• B64D37/04

  Arrangement thereof in or on aircraft · CPC title

• B64D37/32 Primary

  Safety measures not otherwise provided for, e.g. preventing explosive conditions · CPC title

• F16L25/01

  specially adapted for realising electrical conduction between the two pipe ends of the joint or between parts thereof · CPC title

• B64D45/02 Primary

  Lightning protectors; Static dischargers · CPC title

• B64D37/06

  Constructional adaptations thereof · CPC title