Pipe for aircraft fluid circuit comprising a connector having an insertion portion for a tube and assembly method

Abstract

A pipe (1) for a fluid circuit of an aircraft, the pipe (1) extending along a longitudinal axis (X) and comprising at least one tube (2) comprising a connection end (21), a connector (3) comprising at least one connection end piece (4) successively comprising, along the longitudinal axis (X), a free end (5), an insertion portion (6) and a connecting portion (7), the connection end (21) of the tube (2) being configured to be inserted along the longitudinal axis (X), into the insertion portion (6) and into the connecting portion (7) of the connector (3) from the free end (5), so as to mechanically and fluidically connect the tube (2) and the connector (3), the pipe (1) being characterized in that the insertion portion (6) has a flared shape from the connecting portion (7) to the free end (5). Abstract figure: Figure 3

Description

Title of the invention: Pipe for an aircraft fluid circuit comprising a connector having an insertion portion for a tube and assembly method Technical field

[0001] The present invention relates to the field of aircraft fluid circuits. The invention relates in particular to the assembly of pipes intended to be mounted in an aircraft fluid circuit.

[0002] In a known manner, an aircraft fluid circuit comprises a plurality of pipes mechanically and fluidically connected to each other. In practice, with reference to [Fig. 1], each pipe 101 extends longitudinally along an axis X and comprises a tube 102 mechanically connected to a connector 103. Each connector 103 is then connected to a tube 102 of an adjacent pipe 101 (directly or via a fitting) to form the fluid circuit.

[0003] In order to reduce the weight of an aircraft, pipes are increasingly manufactured from a thermoplastic material, and more particularly from a polymer known under the designation PEEK (meaning polyetheretherketone), which allows the manufacture of semi-rigid, light and robust pipes.

[0004] The tube 102 and the connector 103 of such pipes 101 made of thermoplastic material are generally assembled by interlocking and secured by a laser welding process. Alternatively, the tube 102 and the connector 103 can be assembled by friction welding or by gluing for example.

[0005] As is known, laser welding of thermoplastic polymer requires, on the one hand, a component transparent to laser radiation and, on the other hand, a component absorbing the radiation. During laser welding, the radiation-absorbing component (in this example the tube 102) is inserted into the transparent component (in this example the connector 103). A laser beam passes through the transparent component and is absorbed by the absorbing component to form the weld. Laser welding thus makes it possible to join the tube 102 and the connector 103 so as to form a sealed pipe 101.

[0006] In practice, with reference to [Fig.2], when the tube 102 is inserted into the connector 103, to achieve effective welding, it is necessary that the contact pressure between the outer surface 102S of the tube 102 and the inner surface 103S of the connector 103 is uniform over the entire periphery of the pipe 101.

[0007] However, taking into account manufacturing tolerances, the tube 102 and the connector 103, generally cylindrical, may have a deformed section, for example ovalized, as shown in [Fig.2], showing a sectional view of a tube 102 fitted into a connector 103. Such deformation can lead to heterogeneous peripheral pressure between the inner surface 103S of the connector 103 and the outer surface 102S of the tube 102, or even locally a lack of contact, which can lead to welding defects. In addition, it is known to assemble the connector and the tube by shrinking, that is to say by cooling the tube in order to contract it for easier insertion into the connector. Hot shrinking is also known to facilitate the insertion of the tube into the connector. However, such shrinking has the disadvantage of generating excessive stresses in the assembly, which can lead to plastic deformation or even breakage of the components.

[0008] To limit these constraints, it is known to carry out, for example, a conformation of the connector and / or the tube before shrinking, in order to reduce the deviations due to manufacturing tolerances. For this, the elements are heated and their shape is adapted. However, such heating increases cycle times and therefore manufacturing times. In addition, heating consumes energy, which also increases manufacturing costs.

[0009] The invention thus aims to eliminate at least some of these drawbacks, by proposing a simple pipe making it possible to guarantee uniform contact pressure between the tube and the connector, regardless of the deviations due to manufacturing tolerances. PRESENTATION OF THE INVENTION

[0010] The invention relates to a pipe for a fluid circuit of an aircraft, the pipe extending along a longitudinal axis from an upstream to a downstream and comprising: • at least one tube comprising a connection end, • a connector comprising at least one connection end piece comprising successively, along the longitudinal axis, a free end, an insertion portion and a connecting portion, the connection end of the tube being configured to be inserted from upstream to downstream along the longitudinal axis, into the insertion portion and into the connecting portion of the connector from the free end, so as to mechanically and fluidically connect the tube and the connector.

[0011] The invention is remarkable in that the insertion portion has a flared shape from the connecting portion to the free end.

[0012] In other words, the insertion portion has a convergent section whose diameter decreases from the free end towards the connecting portion, that is to say in a direction of insertion of the tube into the connector.

[0013] The pipe according to the invention makes it easier to insert the tube into the connector. The inclined walls of the insertion portion guide the connecting end of the tube along the longitudinal axis and advantageously allow the tube to be centered in the connector, which eliminates the need for perfect alignment at the start of assembly and represents a significant time saving.

[0014] In the event of deformation of the tube, such as an ovalization defect for example, the flared shape of the insertion portion allows progressive contact of the outer surface of the tube against the inner surface of the connector, which makes it possible to increase the stresses on the tube progressively. In other words, such a profile makes it possible to limit the force required to insert the tube into the connector. The progressive contact of a deformed tube in the insertion portion also makes it possible to gradually correct the deformation. The pipe according to the invention thus makes it possible to ensure homogeneous and continuous contact over the entire periphery of the connector and the tube, which makes it possible to limit the risk of assembly defects, for example during a laser welding operation and thus limits the risk of leaktightness of the pipe.Thanks to the connection tip, the contact pressure between the tube and the connector is at least 1 MPa, which allows a quality laser weld to be formed.

[0015] Furthermore, such a flared shape is advantageously simple to implement while being applicable to different pipe diameters.

[0016] In one embodiment, the flared insertion portion has, in a longitudinal sectional plane, a curved half-profile. Such a profile gives the insertion portion a substantially trumpet-shaped shape which makes it easier to center the connection end of the tube in the connection endpiece of the connector. The curved profile also makes it possible, in the event of deformation of the tube for example, to ensure progressive contact by effectively correcting the deformation. The curved profile thus makes it possible to apply a minimum force when inserting the tube into the connector. In other words, such a profile allows optimal guidance of the tube along the insertion portion of the connector, avoiding any risk of damage to the tube or the connector.

[0017] Preferably, the curved profile has a radius of curvature depending on the diameter of the tube and between 50 mm and 150 mm. Such a radius of curvature allows both efficient and progressive guidance and optimal self-centering of the tube in the connector.

[0018] In an alternative embodiment, the flared insertion portion has, in a longitudinal section plane, a rectilinear half-profile. In other words, the insertion portion has a frustoconical shape, which makes it possible to manufacture the connector, the connection end of which is partially flared, in a simple manner.

[0019] Preferably, the insertion portion has an insertion length, according to the longitudinal axis, between 2 mm and 30 mm, which ensures a sufficient length allowing progressive guidance of the tube towards the connecting portion. In the case of a tube with a deformed section, such an insertion length also ensures progressive contact of the deformation, which ensures limiting the appearance of over-stresses in the pipeline and thus guarantees its durability.

[0020] According to a preferred aspect, the free end of the connecting end piece is rounded, advantageously allowing optimal guidance of the tube while limiting the insertion force when connecting the connecting end piece.

[0021] In an alternative embodiment, the free end is chamfered, making it easier to guide and limiting the risk of damage in the event of interference when the tube and the connector come into contact, while allowing the connector to be manufactured simply and inexpensively.

[0022] In one embodiment, the connecting portion has a connecting length, along the longitudinal axis, of between 2 mm and 30 mm. Such a length makes it possible to ensure a sufficient contact surface between the tube and the connector to allow a reliable connection, in which the risk of a leak occurring is limited. The connecting portion corresponds to the portion of the connector in contact with the tube. In the case of assembly by laser welding, for example, such a connecting length also makes the operation easier.

[0023] According to a preferred aspect, the connection end extends into the connection portion over the entire connection length, so as to ensure a reliable assembly which ensures the strength of the connection. This also ensures sufficient coverage to carry out a welding operation for example.

[0024] According to one aspect, the connector comprises a stop to limit the length over which the tube is inserted into the connector.

[0025] Preferably, the tube and the connector are made of a thermoplastic polymer material, so as to form a light and robust pipeline. The tube and the connector can also advantageously be assembled by laser welding to ensure the sealing of the pipeline.

[0026] In one embodiment, the connector comprises at least one second connecting tip configured to cooperate with a second tube, so as to fluidly connect the tube and the second tube.

[0027] The invention also relates to a fluid circuit comprising at least one pipe as described previously.

[0028] Finally, the invention relates to a method of assembling a pipeline as described above, comprising steps consisting of: • position the connection end of the connection fitting opposite the connecting end of a tube, • insert the connection end into the insertion portion of the connection tip, so as to guide the connection end towards the connection portion, and • fit the connection end into the connecting portion, so as to allow uniform peripheral contact between the tube and the connector on the connecting portion.

[0029] Such an assembly method makes it possible to ensure uniform contact pressure between the tube and the connector over the entire periphery of the pipe, making it possible to ensure the tightness of the assembly. The method also makes it possible to guarantee the mechanical strength of the formed pipe, by limiting any risk of damage to the latter, due to the progressive insertion of the tube through the insertion and fitting portions.

[0030] In a preferred embodiment, the method comprises a step of laser welding the tube and the connector at the connecting portion of the connector. Thanks to the connecting tip, the uniform contact pressure between the tube and the connector is at least equal to 1 MPa, which makes it possible to form a quality laser weld.

[0031] In one embodiment, the connection end of the tube is fitted into the connecting portion of the connector over a length of at least between 3 mm and 5 mm, to allow efficient welding.

[0032] Preferably, the method is free from a step of hooping or shaping the tube and the connector. Thanks to the insertion portion according to the invention, the tube and the connector are automatically fitted together with a uniform peripheral pressure, which allows the welding operation to be carried out directly.

[0033] Preferably, the step of fitting the connection end into the connecting portion is carried out by applying a second force of between 500 and 3000 N to the tube. Such a force allows the tube to be forcefully inserted into the connecting portion, while being lower than the limit values ​​for mechanical strength, making it possible to ensure optimal mechanical strength of the pipeline. The insertion force is advantageously lower than the force required in the prior art to fit the tube into the connector, which limits any risk of damage and makes it possible to guarantee the integrity of the tube and the connector. PRESENTATION OF FIGURES

[0034] The invention will be better understood on reading the description which follows, given by way of example, and referring to the following figures, given by way of non-limiting examples, in which identical references are given to objects similar.

[0035] [Fig.l] is a schematic representation of a longitudinal sectional view of a pipeline according to the prior art.

[0036] [Fig.2] is a schematic representation of a cross-sectional view of the pipeline of [Fig.l].

[0037] [Fig. 3] is a schematic representation of a longitudinal sectional view of a pipeline according to a first embodiment of the invention.

[0038] [Fig.4] is a schematic representation of a connector of the pipeline of [Fig.3],

[0039] [Fig.5] is a schematic representation of a pipeline according to a second embodiment of the invention.

[0040] [Fig.6] is a schematic representation of an alignment step of a method of assembling the pipeline according to an embodiment of the invention.

[0041] [Fig.7] is a schematic representation of an insertion step of a method of assembling the pipeline according to an embodiment of the invention.

[0042] [Fig.8] is a schematic representation of a fitting step of a method of assembling the pipeline according to an embodiment of the invention.

[0043] It should be noted that the figures set out the invention in detail to implement the invention, said figures can of course be used to better define the invention where appropriate. DETAILED DESCRIPTION OF THE INVENTION

[0044] The invention relates to a pipe intended to be mounted in a fluid circuit of an aircraft, in particular for the transport of water. It goes without saying that the fluid circuit could just as easily allow the transport of a different fluid, such as fuel or gases. As is known, a fluid circuit comprises several pipes 1 connected to each other so as to guide the fluid.

[0045] [Fig. 3] shows a pipeline 1 according to one embodiment of the invention.

[0046] In this example, the pipe 1 extends longitudinally along an X axis, laterally along a Y axis and vertically along a Z axis, so as to form an orthogonal reference frame (X, Y, Z).

[0047] With reference to [Fig. 3], the pipeline 1 comprises a tube 2 and a connector 3, mechanically connected to the tube 2. In this example, the longitudinal axis X extends from an upstream to a downstream in a direction of connection of the tube 2 in the connector 3.

[0048] In this example, the tube 2 has the shape of a right circular cylinder. Still with reference to [Fig. 3], the tube 2 comprises an inner surface SI, intended to be in contact with the fluid, and a radially opposite outer surface SE. In this example, the outer surface SE defines an outer diameter D2 of the tube 2 of between 10 mm and 60 mm. In practice, in a fluid circuit of an aircraft, the nominal diameter D2 of the tubes 2 is generally of the order of 12.7 mm (1 / 2 inch), 19.05 mm (3 / 4 inch), 25.4 mm (1 inch) or 50.8 mm (2 inches), within manufacturing tolerances. It goes without saying that the invention applies to any diameter of tube configured to be mounted in an aircraft.

[0049] According to one aspect of the invention, the tube 2 comprises a connection end 21 configured to cooperate with the connector 3. In particular, in this example, the connection end 21 of the tube 2 is configured to be fitted into the connector 3, as will be described in more detail later. The connection end 21 has an outside diameter D21 equal to the outside diameter D2 of the tube 2 defined previously, as shown in [Fig. 3].

[0050] Preferably, the tube 2 is made of a thermoplastic polymer material. It goes without saying that the tube 2 could alternatively be made of a different material, for example a metallic material.

[0051] In particular, in this example, the connector 3 and the tube 2 are configured to be fixed to each other by a laser welding method, as will be described in more detail later. As such, the tube 2 is configured to absorb the laser radiation, so as to form the weld. Also, preferably, the thermoplastic polymer is chosen from Polyaryletherketones known by the acronym “PEAK”. In this example, the thermoplastic polymer is a Polyetheretherketone known by the acronym “PEEK”. In particular, in this example, the thermoplastic polymer of the tube 2 is mixed with carbon black, so as to be able to absorb the laser radiation, as will be described in more detail later. It goes without saying that the connector 3 and the tube 2 can alternatively be configured to be fixed to each other in a different manner, for example by gluing or by a different welding method.

[0052] As described previously, the connection end 21 of the tube 2 cooperates with a connector 3 to form the pipe 1. Such a connector 3 is shown in more detail in [Fig.4], according to a first embodiment of the invention.

[0053] According to one aspect of the invention, the connector 3 comprises a connection end piece 4 in order to cooperate with the connection end 21 of the tube 2. In practice, the connection end 21 of the tube 2 is configured to be inserted into the connection end piece 4 of the connector 3 so as to mechanically and fluidically connect the tube 2 and the connector 3.

[0054] For this, still with reference to [Fig.4], the connection end piece 4 comprises successively along the longitudinal axis X, from upstream to downstream, a free end 5, a insertion portion 6 and a linking portion 7.

[0055] The connecting portion 7 is configured to receive the connection end 21 of the tube 2. In other words, the connecting portion 7 corresponds to the portion of the connector 3 in contact with the tube 2. As such, in this example, the connecting portion 7 has a substantially cylindrical shape, complementary to that of the tube 2. In practice, the connecting portion 7 preferably has a slightly frustoconical shape, so as to facilitate the demolding of the connector 3 during its manufacture, as is known to those skilled in the art. In this example, still with reference to [Fig. 4], a convergence angle θ of the frustoconical shape of the connecting portion 7 is defined in a longitudinal section plane (X, Z), the convergence angle θ is preferably of the order of 2°.

[0056] In this example, the connecting portion 7 comprises an inner surface 7S, configured to be in contact with the outer surface 21S of the connection end 21. For this purpose, the connecting portion 7, of frustoconical shape, has, in this example, a minimum inner diameter D7. In this example, the minimum inner diameter D7 is determined so as to guarantee a contact pressure between the assembled tube 2 and connector 3 at least equal to IMPa, corresponding to the pressure necessary to allow laser welding of thermoplastic materials. This makes it possible to insert the tube 2 into the connecting portion 7 with a limited but sufficient force to hold the tube 2 in position in the connecting portion 7, without causing excessive stresses in the pipe 1.

[0057] Preferably, the connecting portion 7 extends over a connecting length L7, defined along the longitudinal axis X, depending on the nominal outside diameter D2 of the tube 2. In this example, the connecting length 7 is between 5 mm and 20 mm, depending on the nominal outside diameter D2 of the tube 2 between 12.7 mm and 50.8 mm (between 1 / 2 inch and 2 inches). Such a connecting length L7 makes it possible to ensure a sufficient contact surface between the tube 2 and the connector 3 to allow an effective connection while guaranteeing its sealing during the assembly of the pipe 1. Such a length also makes it possible, where appropriate, to carry out an assembly by laser welding.

[0058] According to a preferred aspect, the connecting portion 7 comprises a stop 71 (shown in [Fig.3]), so as to limit the connecting length L7 and to limit the insertion of the tube 2 into the connector 3.

[0059] The insertion portion 6 is configured to facilitate the insertion of the tube 2 by guiding the connection end 21 towards the connecting portion 7.

[0060] In this respect, according to one aspect of the invention, the insertion portion 6 has a flared shape from the connecting portion 7 to the free end 5. By “flared shape”, it is meant that the section of the insertion portion 6 has an internal diameter D6 which decreases from the free end 5 to the connecting portion 7, that is to say in the direction from upstream to downstream, along the longitudinal axis X, as shown in [Fig.4],

[0061] In a first embodiment, shown in [Fig. 4], the insertion portion 6 has, in the longitudinal section plane (X, Z) a curved half-profile, to effectively guide the tube 2 into the connecting end piece 4 of the connector 3, as will be described in more detail later. More precisely, the insertion portion 6 is, in this example, tangent to the frustoconical connecting portion 7.

[0062] In particular, still with reference to [Fig. 4], the insertion portion 6 comprises an inner insertion surface 6S, which makes it possible to guide the connection end 21 of the tube 2. In this example, the inner insertion surface 6S of the curved insertion portion 6 has a radius of curvature a of between 50 mm and 150 mm depending on the nominal outside diameter D2 of the tube 2, so as to effectively guide the end of the tube 2 while limiting the size of the connector 3. By way of example, the radius of curvature a is of the order of 150 mm for a tube 2 having a nominal outside diameter D2 of 12.7 mm (1 / 2 inch) and of the order of 50 mm for a tube 2 having a nominal outside diameter D2 of 50.8 mm (2 inches).

[0063] In a second embodiment (not shown), the insertion portion 6 has, in the longitudinal section plane (X, Z), a rectilinear half-profile. In other words, the insertion portion 6 has a frustoconical shape, which makes it easier to manufacture the connector 3, while forming a flared insertion portion 6 into which the tube 2 can be inserted progressively with limited force.

[0064] Preferably, the insertion portion 6 has an insertion length L6, defined along the longitudinal axis X, depending on the nominal outside diameter D2 of the tube 2. In this example, the insertion length L6 is between 5 mm and 15 mm, depending on the nominal outside diameter D2 of the tube 2 being between 12.7 mm and 50.8 mm (between 1 / 2 inch and 2 inches), so as to progressively guide the connection end 21 of the tube 2.

[0065] In one embodiment, the free end 5 of the connecting end piece 4 is rounded, so as to facilitate the insertion of the connection end 21 into the insertion portion 6 while avoiding impacts that could damage said connection end 21. Alternatively, the free end 5 of the connecting end piece 4 has a chamfer, to facilitate the insertion of the connector 3. Preferably, the chamfer is formed at 45°. Preferably, the edges of the free end 5 are shaped or “beveled”, so as to limit any risk of injury or damage to the connector 3. It goes without saying that the free end 5 could just as well be straight and free from any machining.

[0066] Preferably, the connector 3 is made of a thermoplastic polymer material. It goes without saying that the connector 3 could alternatively be made of a different material, for example a metallic material.

[0067] In particular, in this example in which the connector 3 and the tube 2 are configured to be fixed to each other by a laser welding process, the connector 3 (which is external to the tube 2 when the elements are assembled) is configured to allow the laser radiation to pass through, so that it reaches the tube 2 to allow welding. In other words, the connector 3 is preferably made of a transparent material. Also, preferably, the thermoplastic polymer of the connector 3 is chosen from PEAK Polyaryletherketones. In this example, the connector 3 is made of PEEK Polyetheretherketone. In particular, in this example, the beige-colored PEEK-type polymer being naturally transparent to laser radiation, the thermoplastic polymer of the connector 3 is free from any modification such as a coloring treatment in the material, so as to preserve the transparent nature of the material.

[0068] In this example, the connector 3 is a T-shaped connecting fitting which makes it possible to connect at least two tubes 2 of adjacent pipes 1, as shown in Figures 3 and 4. For this purpose, the connector 3 comprises, in this example, two connecting end pieces 4 as described previously mounted facing each other. It goes without saying that the T-shaped connector 3 could comprise three connecting end pieces 4 as described previously to connect three tubes 2. Likewise, it goes without saying that the connector 3 could alternatively be in the form of a straight connecting fitting comprising only two connecting end pieces 4 mounted facing each other to connect two tubes 2 of adjacent pipes.

[0069] In a second embodiment, shown in [Fig. 5], the connector 3 is in the form of a simple connector, known to those skilled in the art under the designation “ferrule” and connected only to the tube 2 of the pipeline 1. The connector 3 thus forms an end piece capable of cooperating with a connecting fitting 8 (for example T-shaped). In other words, in this embodiment, two adjacent tubes 2 are configured to be connected by a connecting fitting 8, each via a ferrule-type connector 3. In this embodiment, the connector 3 is mechanically connected to the connecting fitting 8, for example by screwing, clipping or fitting. In this example, the connector 3 comprises a radial projection 31 which cooperates with an annular groove 81 of the connecting fitting 8 to mechanically connect the connector 3 to the connecting fitting 8.

[0070] A method of assembling a tube 2 and a connector will now be described. 3 so as to form a pipeline 1 with reference to figures 6 to 8. In this example, the connector 3 is a T-shaped connecting fitting. In this example, an operator implements the method, but it goes without saying that the method could alternatively be implemented by a machine tool.

[0071] With reference to [Fig.6], in a first step E1, an operator positions the connection end 21 of the tube 2 opposite the free end 5 of the connector 3.

[0072] The operator then introduces, in a second step E2, the tube 2 into the insertion portion 6 of the connector 3 via the free end 5 in an upstream to downstream movement, as shown in [Fig.7]. In this step E2, the operator applies a first force F1 to the tube 2 by advancing the connection end 21 of the tube 2 along the insertion portion 6. Thanks to the convergent flared profile of the insertion portion 6, the latter advantageously aligns the connection end 21 with the connecting portion 7 along the longitudinal axis X. Thanks to the flared insertion portion 6, the tube 2 is advantageously centered with the connection end piece 4 of the connector 3.

[0073] In a third step E3, shown in [Fig.8], the operator continues the upstream to downstream movement of the tube 2 and inserts the latter into the connecting portion 7 of the connector 3. In this step E3, the operator applies a second force F2, greater than the first force F1, so as to forcefully fit the tube 2 into the connecting portion 7, which makes it possible to ensure optimal contact between the outer surface 21S of the connection end 21 and the inner surface 7S of the connecting portion 7. Optimal contact makes it possible, in this example, to guarantee optimal conditions for laser welding, making it possible to guarantee the sealing of the formed pipe 1. Preferably, the second force F2, a function of the nominal diameter D2 of the tube 2, is between 500 and 3000 N.For example, the second force F2 is of the order of 700N for a tube 2 having a diameter of 12.7 mm (1 / 2 inch), 1000N for a tube 2 having a diameter of 19.05 mm (3 / 4 inch), 1500N for a tube 2 having a diameter of 25.4 mm (1 inch) or even 2000N for a tube 2 having a diameter of 50.8 mm (2 inches). It goes without saying that the values ​​of the second force F2 are given for information purposes only and depend on the assembly conditions of the pipe 1. The second force F2 is thus greater than the first force F1 to allow for forced insertion, while limiting the mechanical stresses in the pipe 1. In this example, once assembled, a contact pressure of IMPa is applied between the tube 2 and the connector 3.

[0074] In this example, the tube 2 and the connector 3 are assembled by laser welding. In a preferred embodiment, the method thus comprises a step of laser radiation welding on the circumference of the connector 3 at the connecting portion 7, hermetically connecting the tube 2 to the connector 3 to form a sealed pipe 1.

[0075] The connector 3 according to the invention advantageously allows simple and rapid assembly of the pipe 1, while guaranteeing uniform contact pressure between the tube 2 and the connector 3 in the connection portion 7. The flared insertion portion 6 makes it possible both to center the tube 2 with respect to the connector 3, to limit the second force necessary for inserting the tube 2 into the connector 3 and to avoid the risk of significant mechanical stresses appearing in the connection.

Claims

Claims

1. Pipe (1) for a fluid circuit of an aircraft, the pipe (1) extending along a longitudinal axis (X) from upstream to downstream and comprising: • at least one tube (2) comprising a connection end (21), • a connector (3) comprising at least one connection end piece (4) successively comprising, along the longitudinal axis (X), a free end (5), an insertion portion (6) and a connecting portion (7), the connecting end (21) of the tube (2) being configured to be inserted from upstream to downstream along the longitudinal axis (X), into the insertion portion (6) and into the connecting portion (7) of the connector (3) from the free end (5), so as to mechanically and fluidically connect the tube (2) and the connector (3), • the pipe (1) being characterized in that the insertion portion (6) has a flared shape from the portion connecting (7) to the free end (5).

2. Pipe (1) according to claim 1, in which the insertion portion (6) has, in a longitudinal section plane, a curved half-profile.

3. Pipe (1) according to claim 1, in which the insertion portion (6) has, in a longitudinal section plane, a rectilinear half-profile.

4. Pipe (1) according to one of claims 1 to 3, in which the free end (5) of the connecting end piece (4) is rounded.

5. Pipe (1) according to one of claims 1 to 3, in which the free end (5) of the connecting end piece (4) is chamfered.

6. Pipe (1) according to one of claims 1 to 5, in which the tube (2) and the connector (3) are made of a thermoplastic polymer material.

7. Pipe (1) according to one of claims 1 to 6, in which the connector (3) comprises at least one second connection end piece (4) configured to cooperate with a second tube, so as to fluidically connect the tube (2) and the second tube.

8. Fluid circuit comprising at least one pipe (1) according to one of claims 1 to 7.

9. Method for assembling a pipe (1) according to one of claims 1 to 7, comprising steps consisting of: • positioning (El) the connection end piece (4) of the connecting connector (3) opposite the connection end (21) of a tube (2), • inserting (E2) the connection end (21) into the insertion portion (6) of the connection end piece (4), so as to guide the connection end (21) towards the connection portion (7), and • fitting (E3) the connection end (21) into the connection portion (7), so as to allow uniform peripheral contact between the tube (2) and the connector (3) on the connection portion (7).

10. Assembly method according to claim 9, comprising a step of laser welding the tube (2) and the connector (3) at the level of the connecting portion (7) of the connector (3).

11. Assembly method according to one of claims 9 to 10, in which the step of fitting (E3) the connection end (21) into the connecting portion (7) is carried out by applying to the tube (2) a second force (F2) of between 500 and 3000 N.

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