Abstract: A process for the production of a vessel for high pressure gas, particularly helium, for a space launcher or for a satellite with a short lifetime. The process includes the step of producing an internal skin of a plastic material selected from polyethylene and crystallized polyamide. The process also includes winding a reinforcement of fibers and resins around the internal skin, and then providing the obtained vessel with the necessary conduits and control valves.

Abstract: The aim of the present invention is a process for manufacturing boron nitride fibers, in particular continuous boron nitride fibers with good mechanical properties, which may be used for producing ceramic composite materials such as BN/BN composites, thermostructural parts or antenna radomes. It provides and uses a precursor polymer of formula (I) below: in which n is a whole number, R1 and R2, identical or different, represent independently an alkyl group, and R3 represents an amino group, a hydrogen atom, an alkyl, a cycloalkyl or a boryl.

Abstract: A process for the production of a vessel for high pressure gas, particularly helium, for a space launcher or for a satellite with a short lifetime, includes the steps of: a production of an internal skin of a plastic material selected from polyethylene and crystallized polyamide, a winding a reinforcement of fibers and resins, and a providing the obtained vessel with the necessary conduits and control valves.

Abstract: A process for selectively lacing filaments on multi-dimensional textile preforms made of rods, the rods are displaced by the filament and pressed vertically downwardly by a needle with an open eye which, after passing through the piece to be laced, is opened at an insertion station for the filament to receive the filament, then is raised to pass the filament through the space freed by the rod.

Abstract: The pointed end of a central spike, used in an engine of a space launcher, may have a deformable structure that can adopt either a folded position or a deployed position.

Abstract: A weaving device for the production of thick textile armatures constituted by superposed layers of threads secured together by a binding thread traversing the layers, includes a frame provided laterally and at its periphery with regularly distributed hooking pins, elements for depositing with the aid of the pins, thread and elements for flattening the layers. The pins have a first section with a slight inclination outwardly of the frame and a second straight section prolonging the first and having an a substantially greater inclination outwardly of the frame. The elements for depositing thread include a plurality of guides each supplying a thread, and are moved simultaneously and spaced at an interval equal to n times the interval between pins. The elements for weaving the layers include elements adapted to press the assembly of the layers about their periphery.

Abstract: The temporary connection of two elements (12, 14) is ensured by U-shaped connecting components (16) held in place by a moving part (18). A pyrotechnic composition (20) is housed between two shoulders (32, 36) situated respectively on the first of the elements (12) and on the moving part. Igniting the pyrotechnic composition (20) causes the moving part (18) to slide over the first element (12). The connecting components (16) are released and the connection between the elements (12, 14) is eliminated without breaking any parts.

Abstract: The temporary connection of two elements (12, 14) is ensured by U-shaped connecting components (16) held in place by a moving part (18). A pyrotechnic composition (20) is housed between two shoulders (32, 36) situated respectively on the first of the elements (12) and on the moving part. Igniting the pyrotechnic composition (20) causes the moving part (18) to slide over the first element (12). The connecting components (16) are released and the connection between the elements (12, 14) is eliminated without breaking any parts.

Abstract: The invention concerns a method for making boron nitride fibers by drawing a polymer precursor and treating with ceramics the polymer fibers obtained by drawing. The invention is characterized in that the precursor polymer is obtained by thermal polymerization of a borazine of formula (I) wherein: R1, R3, R4 and R5, identical or different, represent an alkyl, cycloalkyl or aryl group; and R2 represents a hydrogen atom or an alkyl, cycloalkyl or aryl group.

Abstract: The invention concerns a method for manufacturing a tank (1) for fluids under pressure comprising two compartments (8, 10).

Abstract: The aim of the present invention is a process for manufacturing boron nitride fibres, in particular continuous boron nitride fibres with good mechanical properties, which may be used for producing ceramic composite materials such as BN/BN composites, thermostructural parts or antenna radomes.

Abstract: The invention relates to a process for selectively lacing filaments on multi-dimensional textile preforms made of rods, in which the rods are displaced by the filament, the rods being pressed vertically downwardly by a needle (3) of the type with an open eye which, after passing through the piece to be laced and ejection of the rod, is opened at a so-called insertion station (9) for the filament to receive the filament to be laced (21), then is raised to pass the filament through the space freed by said rod, characterized by the following steps:

Abstract: A temporary connection and pyrotechnic separation device (10) normally connects two elements (12, 14). This device comprises a connecting part (18), of which a bottom portion (38) is fixed to one (12) of the elements. Active portions (40) of the connecting part (18) cover a space (20) in which there is pyrotechnic expansion tube (16). The active portions are deformable and comprise hook-shaped ends (50) that fit into a notch (36) formed in the second element (14), so that normally there is a pressure connection between the two elements. The effect of firing is to deform the active parts and consequently break this pressure connection.

Abstract: The invention concerns a dome (34) consisting of a round-shaped vessel (30) provided with an opening (28) at the top and by a cap (33) welded on said basin to close said opening (28). The basin is obtained by hot forming under pressure of a truncated blank (5) made of non tempered aluminum alloy.

Abstract: The present invention concerns high performance boron nitride fibres and a process for manufacturing said fibres.

Abstract: A pyrotechnic actuator comprises a deformable membrane (24) separating a first chamber (20), which is able to receive pyrotechnic combustion gases, from a second chamber (22) containing a control member (32) displaceable by the membrane (24) during the operation of the actuator. In the inoperative state, the membrane (24) is prestressed counter to its deformation controlled by the intake of gases into the first chamber (20). In this way the functional travel is increased, which e.g. makes it possible to open or close a circuit with a larger cross-section without increasing the actuator size.

Abstract: A pyrotechnic actuator comprises a deformable membrane (24) separating a first chamber (20), which is able to receive pyrotechnic combustion gases, from a second chamber (22) containing a control member (32) displaceable by the membrane (24) during the operation of the actuator. In the inoperative state, the membrane (24) is prestressed counter to its deformation controlled by the intake of gases into the first chamber (20). In this way the functional travel is increased, which e.g. makes it possible to open or close a circuit with a larger cross-section without increasing the actuator size.