The present invention relates to a pipe support, an aircraft assembly including the pipe support, a fixed wing aircraft including the aircraft assembly, and a method of assembling a pipe with an aircraft structural member.
Aircraft wing boxes can be provided with fluid conduits, such as fuel conduits, that extend through openings in structural supports, such as ribs.
Conduit supports are used to attach the fluid conduits to the structural supports. Such conduit supports are typically attached using threaded fasteners, such as nuts and bolts which are complicated and time consuming to install.
One approach is to mount pipe connectors to either side of an opening in a rib. Individual pipe sections are joined between the connectors on adjacent ribs to form the fluid conduit. The pipe connectors act as conduit supports. Such an approach is time consuming and complex.
Another approach is to mount a pair of support plates on either side of the pipe and mount them to the rib using bolts or rivets.
According to an aspect of the present invention, there is provided a pipe support for an aircraft fuel system, the pipe support comprising a first part and a second part which together form a collar configured to retain a pipe, the pipe support being movable between an open condition, in which the pipe is insertable between the first and second parts, and a closed condition, in which the first and second parts are brought together to retain the pipe, wherein at least part of the collar is configured to be disposed in an opening in a structural member so that, when the at least part of the collar is in the opening, the pipe support is restricted from moving from the closed condition.
With such an arrangement, it is possible to straightforwardly mount a pipe support, and so simply support a pipe at a structural member, such as a wing rib, with a minimum of components. The above arrangement, helps to restrict the need to provide fasteners to restrict the first and second parts from being separated. As such, the pipe support makes use of the opening in the structural member through which the pipe extends to retain the pipe support in a closed condition. The need for additional openings in the support member is minimised.
The pipe support helps to minimise excessive tolerances, and reduce abrasive contact.
The pipe support may be configured to clamp the pipe between the first and second parts.
The pipe support may have a clamshell arrangement.
The pipe support may comprise a hinge about which the first part and the second part are separable.
With such an arrangement, it is possible to simplify assembly of the pipe support with the pipe. For example, a one-handed assembly operation is possible.
The pipe support may comprise a flange on the collar.
The flange may be configured to abut against the structural member to limit movement of the pipe support in a longitudinal axial direction of the pipe when the collar is in the opening.
The flange may comprise a first flange portion on the first part and a second flange portion on the second part.
The flange may extend circumferentially about the collar.
The pipe support may comprise a bayonet fitting.
As such, it is possible to provide a simple mounting means.
The bayonet fitting may comprise a bayonet tab configured to be inserted through a corresponding slot of the opening in the structural member, and to abut against the structural member upon rotation of the pipe support when the at least part of the collar is in the opening, so that a portion of the structural member is engaged between the flange and the bayonet tab.
The bayonet tab may be a first bayonet tab, and the bayonet fitting may comprise at least one second bayonet tab.
The first bayonet tab may have a different profile to the at least one second bayonet tab. Such an arrangement helps to ensure that the pipe support is orientated in a specific orientation with respect to the structural member when disposing the collar in the opening.
The pipe support may comprise a stop configured to limit rotation of the at least part of the collar in the opening.
The pipe support may comprise a fixing configured to fix the pipe support with the structural member to prevent rotation of the pipe support in the opening when the at least part of the collar is in the opening.
The pipe support may comprise a flange seal on the flange.
The flange seal may be a circumferentially extending flange seal.
A maximum radial length of the or each bayonet tab may be less than the radial distance of the circumferentially extending seal.
The flange seal may be electrically conductive to provide a conductive path between the pipe support and the structural member. As such an electrical bond may be provided to ensure an electrical path without a need for separate bonding leads, and to reduce any associated preparation.
The pipe support may comprise a collar seal on the collar.
The collar seal may be electrically conductive to provide a conductive path between the pipe and the pipe support. As such an electrical bond may be provided to ensure an electrical path without a need for separate bonding leads, and to reduce any associated preparation.
The pipe support may be electrically conductive.
The pipe support may be electrically isolating.
According to an aspect of the present invention, there is provided an aircraft assembly comprising: a fluid pipe, a structural member having an opening through which the pipe extends, and a pipe support as set out above, wherein the pipe support supports the fluid pipe at the opening.
The structural member may be a rib defining a rib plane. The fluid pipe may extend through the rib plane.
The pipe may have a cross-section that is uninterrupted as the pipe extends through each rib.
The pipe may be configured to carry fuel.
According to an aspect of the present invention, there is provided a fixed wing aircraft comprising at least one of the pipe support as set out above and the aircraft assembly as set out above.
According to an aspect of the present invention, there is provided a method of supporting a pipe on a structural member of an aircraft, the method comprising the steps: disposing a pipe through an opening in the structural member, inserting the pipe between a first part and a second part of a pipe support in an open condition, moving the pipe support into a closed condition in which the first and second parts are brought together to form a collar with the pipe retained by the collar, and disposing the collar in an opening in the structural member so that the first and second parts are restricted from moving from the closed condition.
Embodiments of the invention will now be described with reference to the accompanying drawings, in which:
Each wing has a cantilevered structure with a length extending in a span-wise direction from a root to a tip, the root being joined to an aircraft fuselage 4. The wings 2, 3 are similar in construction so only the starboard wing 3 will be described in detail with reference to
The aircraft 1 includes a centre wing box 9 within the body of the fuselage 4. The centre wing box 9 is joined to an inboard rib 14a which forms the root of the wing 3. The wing 3 includes a series of spaced ribs 14 between the inboard rib 14a and an outboard rib 14b at the starboard wing tip. Each rib 14 defines a rib plane. The rib plane of each rib extends substantially parallel to the or each adjacent rib plane. The orientation of adjacent ribs with respect to each other may vary. The rib plane extends substantially parallel to a chord axis of the wing 3. The ribs 14 form part of a wing box on the starboard wing 3 the wing box 9 also including a front spar 10 and an upper skin cover 11, a rear spar 12, and a lower skin cover 13.
In the following description, the term “front” refers to components towards a leading edge 7 of the wing, and the term “rear” refers to components towards a trailing edge 8 of the wing. The terms “forward” and “rearward” shall be construed accordingly. The position of features may be construed relative to other features, for example a forward component may be disposed on a forward side of another component, but towards the rear of the vehicle. Similarly, the terms “upper” and “lower” refer to the position of features relative to other features and in accordance with a normal orientation of the aircraft 1.
In an existing wing box shown in
In an alternative arrangement of pipe supports, as shown in
The pipe 22 is a fluid pipe, such as a fuel pipe, a vent pipe or scavenge pipe. The pipe 22 may be configured to carry a liquid and/or a gas. The pipe 22 has a generally uniform cross-section along its length. This aids fluid flow, and restricts flow disturbances. The pipe 22 extends through the opening 17. The diameter of the pipe 22 is smaller than the peripheral dimensions of the opening 17.
A pipe support 40 mounts the pipe 22 in the region of the rib 14 to the rib 14. The rib 14 acts as a structural member. The pipe support 40 restricts movement of the pipe 22 and helps to reduce chaffing. As will be described below, attaching the pipe 22 to the rib 14 using the pipe support 40 is a convenient means of assembling the pipe 22 across multiple ribs 14 without the need to divide the fluid pipe into multiple sections that individually transverse each rib bay. Instead the pipe 14 is provided in the one uninterrupted fluid pipe 14 that extends through multiple ribs 14. As such, the parts count and complexity of the assembly may be simplified.
The pipe support 40 will now be described in detail with reference to
The first and second parts 41, 42 are connected by a hinge 47. The first and second parts 41, 42 are hingedly mounted to each other. The hinge 47 ensures alignment of the first and second parts 41, 42 when the pipe support 40 is moved into its closed condition. As such, the first and second semi-circular channels 45, 46 are aligned with each other to define the aperture 44. The hinge 47 is a pin pivot. Alternative hinge arrangements may be used. The pipe support 40 is formed as a clam-shell configuration. The hinge 47 is offset from the first and second parts 41, 42 to allow the pipe support 40 to move easily between the open and closed conditions.
The aperture 44 is configured to receive the pipe 22. As such, the diameter of the aperture 44 substantially corresponds to the outer diameter of the pipe 22. In embodiments, the diameter of the aperture 44 is slightly greater than the outer diameter of the pipe 22, for example to allow the pipe 22 to move during wing bending.
The pipe support 40 comprises a collar 50. The collar 50 is formed by the first and second parts 41, 42. The body 43 of the pipe support 40 is split into the first and second parts 41, 42 along a diametric plane along which the first and second parts 41, 42 are brought into abutment in the closed condition. The collar 50 has an internal face 51 defining the aperture 44. The aperture 44 is a bore through the collar. It will be understood that the collar 50 is separable along the diametric plane when the first and second parts 41, 42 are moved from the closed condition into the open condition, as shown in
A collar seal 55 extends around the aperture 44. The collar seal 55 protrudes from the collar internal face 51. The collar seal 55 is partially received in a collar seal channel 56 in the collar internal face 51. The collar seal 55 comprises a first collar seal portion 55a and a second collar seal portion 55b. The first and second collar seal portions 55a, 55b are on the first and second parts 41, 42 respectively. The collar seal 55 is separable into the two portions when the first and second parts 41, 42 are moved from the closed condition. The collar seal 55 forms a circumferentially extending sealing arrangement when the pipe support 40 is in the closed condition. The collar seal 55 is formed as a split O-ring arrangement, however alternative configurations are anticipated.
The body 43 of the pipe support 40 is formed from a conductive thermoplastic, for example a carbon fibre reinforced nylon. The collar seal 55 is formed from a conductive elastomeric material. The collar seal 55 is configured to directly contact the pipe 22 when the pipe 22 is received by the pipe support 40. By providing a conductive elastomeric seal it is possible to achieve an electrical bond between the pipe 22 and the pipe support 40 through the collar seal 55. When the first and second parts 41, 42 are moved into the closed condition with the pipe 22 received therebetween, the first and second parts 41, 42 are configured to clamp the pipe 22 in the aperture 44. The collar seal 55 is resilient and biases against the pipe 22.
The body 43 comprises a flange 60. The flange 60 is at one end of the collar 50. The flange 60 extends circumferentially around the collar 50. The flange 60 extends radially outwardly from the collar 50. The flange 60 is generally planar. The first and second parts 41, 42 together define the flange 60. The flange 60 comprises a first flange portion 60a and a second flange portion 60b. The hinge 47 extends between the first and second flange portions 60a, 60b. The flange 60 comprises a locating face 61. The locating face 61 is configured to be brought into abutment with the rib 14. The flange 60 restricts movement of the pipe support 40 relative to the rib 14 in an axial direction of the pipe 22.
The flange 60 comprises a flange seal 65. The flange seal 65 extends circumferentially. The flange seal 65 is configured to locate against one of the faces 14a, 14b of the rib to provide sealing thereagainst. The flange seal 65 is received in a flange channel 66. The flange channel 66 extends circumferentially around the locating face 61. The flange seal comprises a first flange seal portion 65a and a second flange seal portion 65b. The first and second flange seal portions 65a, 65b are on the first and second parts 41, 42 respectively. When the pipe support 40 is in the closed condition, the first and second flange seal portion 65a, 65b form a circumferentially extending seal.
The flange seal 65 is formed from a conductive elastomeric material. The flange seal 65 protrudes from the locating face 61. When the locating face 61 is brought into abutment with the rib 14, an electrical path is formed between the pipe 40 and the rib 14. As such it is possible to achieve an electrical bond between the pipe support 40 and the rib 14, through use of the pipe support 40 only. It is therefore possible to provide an electrical bond between the pipe 22 and the rib 14 through use of the pipe support 40 without the need for further components such as separate bonding leads.
A fixing 70 is provided. The fixing 70 is configured to fixedly locate the pipe support 40 with respect to the rib 14 and to prevent relative rotation of the pipe support 40 with the rib 14 when mounted thereto. In the present arrangement, the fixing comprises a nut and bolt arrangement 71, for example a self-retaining nut, acting as a threaded fastener configuration, which is receivable through a fixing hole 72 (as shown in
The pipe support 40 comprises a bayonet fitting 80. The bayonet fitting 80 comprises a male bayonet arrangement 81. The male bayonet arrangement 81 is on the collar 50. The male bayonet arrangement 81 is at the other end of the collar 50 to the flange 60. A rib receiving gap 83 is defined between the male bayonet arrangement 81 and the flange 60.
The bayonet fitting 80 comprises a plurality of bayonet tabs 85. The bayonet tabs 85 protrude from the collar 50. The bayonet tabs 85 extend radially outwardly from the collar 50. The bayonet tabs 85 include a first bayonet tab 85a and two second bayonet tabs 85b. It will be understood that the number of bayonet tabs 85 may differ. The first bayonet tab 85a has a different profile to the second bayonet tabs 85b. The first bayonet tab 85a is larger than the second bayonet tabs 85b. In the present arrangement the width of the first bayonet tab 85a is greater than the width of the second bayonet tabs 85b, although other dimensions may differ, such as the length of the respective bayonet tabs. It will be understood that the shape of the bayonet tabs 85 may differ from that shown.
The distance between the bayonet tabs 85 and the flange 60 substantially corresponds to the thickness of the rib 14 about the opening 17. The respective angular distance between the bayonet tabs 85 may differ. In the present configuration, as shown in the figures, the first bayonet tab 85a is split between the first and second parts 41, 42 with one second bayonet tab 85b being formed on each of the first and second parts 41, 42.
Referring now in particular to
The radius of the opening wall 90 is less than the radial extent of each of the bayonet tabs 85.
As shown in
Assembly of the aircraft assembly 30 will now be described with reference to
The pipe 22 may be received by the pipe support 40 by holding the pipe support 40 in an open condition as shown in
In
The pipe support 40 is aligned with opening 17. The male bayonet arrangement 81 is aligned with the opening 17, acting as the female bayonet arrangement 82. That is the relative bayonet tabs 85 are aligned with the respective opening slots 91. The provision of the first bayonet tab 85a and the first opening slot 91a in which both have a different profile to the second bayonet tabs 85b and second opening slots 91b helps to ensure that the pipe support 40 is correctly aligned with the opening 17. In particular, such an arrangement helps to ensure that the fixing hole 72 aligns with the locking hole 73 when the pipe support 40 is in the engaged position with the rib 14.
When the male and female bayonet arrangements 81, 82 are aligned the collar 50 is inserted into the opening 17. The collar 50 is therefore disposed in the opening 17. The collar 50 extends through the opening 17. As such, the rib 14 is disposed between the bayonet tabs 85 and the flange 60. The rib receiving gap 83 corresponds to the thickness of the rib 14 about the opening 17. As such, the pipe support 40 is able to be rotated about the pipe 22 and relative to the rib 14 so that at least a portion of the rib 14 is received in the rib receiving gap 83 between the flange 60 and the bayonet tabs 85.
When the pipe support 40 is received by the opening 17, the first and second parts 41, 42 are restricted from being separable from each other. As such, the pipe support 40 is retained in the closed condition without the need for any additional components, such as fixings. The rib 14 itself acts to maintain the pipe support 40 in the closed condition. As such, the provision of a pipe support is simplified.
The pipe support 40 may then be rotated about the pipe 22 to move the pipe support 40 into the engaged position with the rib 14. As shown in
When the fixing hole 72 is aligned with the locking hole 73, the fixing 70 may be engaged to lock the pipe support 40. When the fixing 70 is engaged, relative rotation of the pipe support 40 with the rib 14 is prevented. As such, it is not possible to move the pipe support 40 from the engaged position, so that the pipe support 40 is in a locked condition as shown in
Referring to
When the pipe support 40 is in the engaged position, the flange 60 abuts the first rib face 14a of the rib 14. The flange seal 65 is biased against the rib 14. As the flange seal is electrically conductive, the pipe support 40 and the rib 14 are electrically bonded to each other. The flange seal provides an external seal to prevent fluid leakage through the opening 17. The flange seal 60 prevents leakage between the rib 14 and the pipe support 40. Through the provision of the collar seal 55 and the flange seal 65 it is possible to maximise the sealing capability provided by the pipe support 40. The pipe support 40 restricts the fluid path across the rib 14 through the openings 17.
Although in the above described embodiments the collar seal 55 and the flange seal 65 are electrically conductive, it will be understood that one or more of the seals 55, 65 and the pipe support 40 may be formed from an electrically insulating material to prevent the provision of an electrical path between the rib 14 acting as a structural member, and the pipe 22.
It will be understood that the aircraft assembly may be disassembled by disengaging the fixing 70 and rotating the pipe support 40 from the engaged position to the inserted position. As such, the pipe support 40 may then be withdrawn from the rib 14. As such, the pipe support 40 is replaceable or interchangeable.
Where the word ‘or’ appears this is to be construed to mean ‘and/or’ such that items referred to are not necessarily mutually exclusive and may be used in any appropriate combination.
Although the invention has been described above with reference to one or more preferred embodiments, it will be appreciated that various changes or modifications may be made without departing from the scope of the invention as defined in the appended claims.
Number | Date | Country | Kind |
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1814439.4 | Sep 2018 | GB | national |