METHOD FOR PRODUCING AN ESPECIALLY LARGE AERONAUTICAL PART

Abstract

The present disclosure relates to a method for producing a final metal part for a nacelle of a turbojet. The method includes brazing at least two parts, one being an inner part having an inner surface and the other being an outer part having an outer surface. The method further includes a step of heating the outer surface of the outer part using an external heating means, and a step of heating the inner surface of the inner part using an internal heating means.

Claims

1. A method for manufacturing a metal final part of turbojet engine nacelle, the method comprising: brazing of at least two parts, the two parts comprising an inner part having an inner surface and an outer part having an outer surface; heating the outer surface of the outer part by an outer heating means; and heating the inner surface of the inner part by an inner heating means.

2. The method according to claim 1, wherein the step of heating the inner surface of the inner part by the inner heating means is simultaneous with the heating step of the outer surface of the outer part by the outer heating means.

3. The method according to claim 1, further comprising a cooling step by a gas of at least one heating means.

4. The method according to claim 3, wherein the cooling step is performed by means of an inert gas.

5. The method according to claim 3, wherein the cooling step is performed by means of argon.

6. The method according to claim 1, wherein the metal final part is manufactured from titanium.

7. The method according to claim 1, wherein the metal final part is a revolution part.

8. The method according to claim 1, wherein the metal final part is an inner fixed structure.

9. The method according to claim 1, further comprising a heating step at a temperature greater than necessary so as to reduce the brazing cycle time.

10. A brazing device manufactured according to the method of claim 1.

11. The method according to claim 10, further comprising a heating step by an inner heating means.

Description

DRAWINGS

[0029] In order that the disclosure may be well understood, there will now be described various forms thereof, given by way of example, reference being made to the accompanying drawings, in which:

[0030] FIG. 1 is a schematic representation of a brazing device for manufacturing a metal final part according to one form of the present disclosure.

[0031] The drawings described herein are for illustration purposes only and are not intended to limit the scope of the present disclosure in any way.

DETAILED DESCRIPTION

[0032] The following description is merely exemplary in nature and is not intended to limit the present disclosure, application, or uses. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.

[0033] With reference to FIG. 1, there is described a brazing device 1 comprising an furnace 2 having an inner wall 3 whose shape constitutes the outer shape of the metal final part to be produced.

[0034] The furnace 2 may have a cylindrical bulk.

[0035] The furnace 2 may be under vacuum.

[0036] The furnace 2 comprises an outer heating means 10 which may be one or more outer network(s) of heating resistors 10, for example an outer network of heating resistors 10.

[0037] In this form, the metal final part to be produced is an acoustic sandwich structure 4 of revolution comprising two skins, one being an acoustically reflective skin 5 and the other being an acoustically transparent skin 6 between which a honeycomb structure 7 is interposed. The acoustic sandwich structure 4 is a component of an inner fixed structure (IFS or Internal Fixed Structure) intended to form the roll of the inner fixed structure.

[0038] The brazing device 1 further comprises an inner brazing tool 8 whose diameter may be slightly lower than the diameter of the part to be deformed and to be brazed on an already deformed and brazed part, if desired. In the example shown in FIG. 1, the diameter of the inner tool 8 is slightly lower than the diameter of the acoustically reflective skin 5.

[0039] The outer network of heating resistors 10 is operable to heat the outer surface of the acoustically transparent skin 6, the honeycomb structure 7 and the acoustically reflective skin 5 to allow the brazing, in the example of FIG. 1, of the acoustically reflective skin 5 and the acoustically transparent skin on the honeycomb structure 7.

[0040] Furthermore, the brazing device 1 comprises an inner heating means 9 which may be one or more inner network(s) of heating resistors 9, for example, an inner network of heating resistors 9 operable to heat the inner tool 8 and the inner surface of the acoustically reflective skin 5 to cause a differential expansion of the inner tool 8 which thus allows shaping, sizing, and promotes the acoustically reflective skin 5 to come alongside the acoustically transparent skin 6 with the honeycomb structure 7 during the brazing.

[0041] During the brazing, the acoustically reflective skin 5 comes alongside the honeycomb structure 7 such that its outer surface comes into contact and takes the shape of the surface of the opposite honeycomb structure 7, while the acoustically transparent skin 6 comes alongside the honeycomb structure 7 so that its inner surface comes into contact and takes the shape of the surface of the opposite honeycomb structure 7.

[0042] In one form, the acoustically reflective and transparent skins 6 may be manufactured from titanium.

[0043] The inner 9 and outer 10 networks of heating resistors heat simultaneously the parts to be brazed 5, 6 and 7 and the inner tool 8.

[0044] Thus, due to the presence of an inner network of heating resistors 9 besides the outer network of heating resistors 10, and the simultaneous heating thereof for the brazing of the acoustic sandwich structure, the temperature gradients and the heating times are reduced between two points located at any location on the acoustically reflective 5 and/or transparent 6 skins and/or the honeycomb structure 7.

[0045] Such a brazing device provides for reducing the brazing cycle time and reducing the brazing temperatures due to the fact that the parts to be brazed are better heated and in more homogeneous manner.

[0046] It goes without saying that the present disclosure is not limited to the variations described above by way of example but it comprises all technical equivalents and the variants of the means described above as well as the possible combinations thereof.

[0047] The description of the disclosure is merely exemplary in nature and, thus, variations that do not depart from the substance of the disclosure are intended to be within the scope of the disclosure. Such variations are not to be regarded as a departure from the spirit and scope of the disclosure.