Pressure bulkhead made of composite material for an aircraft
View Patent ↗The present invention relates to a curved rear pressure bulkhead ( 1 ) made of a composite material, comprising three layers: an outer layer ( 2 ) and an inner layer ( 3 ) symmetrical with one another, which are made of a fiber laminate, and the intermediate layer or core ( 4 ) made of a lightweight material. With such a sandwich-type shape, the resulting bulkhead ( 1 ) is able to withstand the bending loads coming from the strain and pressurization of the fuselage without having to increase its stiffness by means of using some type of stiffener. The bulkhead ( 1 ) comprises a ring ( 6 ) that is attached to the ends of the sandwich shape. This ring ( 6 ) is split into several parts ( 8 ) to facilitate the assembly of the bulkhead ( 1 ) made of composite material to the fuselage skin ( 5 ).
1. A manufacturing process for manufacturing a rear pressure bulkhead ( 1 ) made of composite material for aircraft fuselage made of a single piece of composite material having a unitary composition throughout said bulkhead, said bulkhead comprising three layers: an outer layer ( 2 ) made of a fiber laminate, an inner layer ( 3 ) made of a fiber laminate and an intermediate layer or core ( 4 ) made of a lightweight material, the laminate of the outer layer ( 2 ) an inner layer ( 3 ) being symmetrical one another, said method comprising the following steps:
a) curing the layer of the core ( 4 ) with a planar plate shape;
b) heat machining and forming the layer of the core ( 4 ) so that it acquires its final shape;
c) stabilizing the layer of the core ( 4 ) so that its shape is not modified during the final curing of the bulkhead ( 1 );
d) laminating the outer and inner laminates ( 2 ), ( 3 ) of the bulkhead ( 1 ) with a fiber placement machine or manually on a male jig on both sides of the layer of the core ( 4 ); and
e) curing the assembly of the laminates ( 2 ), ( 3 ) and the core ( 4 ) in an autoclave wherein said bulkhead is able to sufficiently withstand strain and pressurization of the aircraft fuselage without any additional stiffening agents.
2. A method as claimed in claim 1 , wherein said rear pressure bulkhead has an end ( 9 ) formed by a fiber laminate, said end ( 9 ) is affixed to a ring ( 6 ) that is attached to the aircraft fuselage.
3. A method as claimed in claim 2 , wherein said ring ( 6 ) is divied into pieces ( 8 ).
4. The method of claim 1 , wherein the core ( 4 ) is made of foam.
5. The method of claim 1 , wherein the core ( 4 ) is honeycomb-like.
6. The method of claim 1 , wherein the composite material is CFRP.
7. The method of claim 1 , wherein an adhesive layer is applied between the outer layer ( 2 ) and the core ( 4 ) and between the inner layer ( 3 ) and the core ( 4 ).
8. A rear pressure bulkhead ( 1 ) for aircraft fuselage made of a composite material whenever obtained by the method of claim 1 .