Abstract: A structure, made from composite materials for a vehicle chassis, being configured to receive an undercarriage at its ends and includes at least one central beam that includes a median box having a central part and two ends with a reinforced structure, and the central part includes a reinforced part increasing the strength of the beam with respect to the bending stresses imposed by the transported load. The median box is reinforced by two lateral boxes extending over the entire length of the median box), assembled to the median box, the upper faces of which, together with the upper face of the median box, form the upper face of the beam. The structure includes a floor that covers the upper faces of the median box and the lateral boxes. The elements making up the structure have shapes that are simple, easy to make from composite materials and easy to assemble.

Abstract: A device for depositing in contact roving of pre-impregnated fibers in which at least one roving (F) is, in the course of a deposition sequence, unrolled from a spool (19) or the like, pressed and deposited on the surface (9) to be covered with the help of a deposition roller (11) or the like, then cut when the desired length of roving is deposited. Substantially from beginning to end of each deposition sequence the roving (F) is maintained in contact with the roller (11), the roving being unrolled substantially under only the tension of the roller and deposited and held, at least at the beginning and at the end of the deposition path, pressed against the surface to be covered, and, at the end of the deposition sequence, spacing the deposition roller (11) from the surface (9), then cutting the roving in its portion between the roller and the surface. Useful in the production of structures of composite material.

Abstract: Method for producing a connecting rod, particularly a monoblock composite connecting rod, and the resulting connecting rod is provided by placing preimpregnated fibers on an extractable mandrel, with the following successive stages. Embodying on a rigid central shaft a meltable mandrel with a shape corresponding to that of the connecting rod; winding and/or laying down the preimpregnated fibers according to a predetermined number of layers and an inclination of the fibers with respect to the longitudinal axis of the mandrel; polymerization with a homogeneous compacting pressure being applied to the entire outer surface of the unit; and then final operations for removing the mandrel and machining to required dimensions of the connecting rod.

Abstract: A method for producing a connecting rod, particularly a monoblock composite connecting rod, by placing preimpregnated fibers on an extractable mandrel, with the following successive stages. Embodying on a rigid central shaft a meltable mandrel with a shape corresponding to that of the connecting rod; winding and/or laying down the preimpregnated fibers according to a predetermined number of layers and an inclination of the fibers with respect to the longitudinal axis of the mandrel; polymerization with a homogeneous compacting pressure being applied to the entire outer surface of the unit; and then final operations for removing the mandrel and machining to required dimensions of the connecting rod.

Abstract: A composite material tube, substantially insensitive to the variations of elongation under the effect of the internal pressure, comprising a number n of stable layers of reinforcement fibers, the fibers of each layer (i) being placed at the same winding angle in absolute value, referenced theta, with respect to the axis of the tube with an equal proportion of fibers wound at said angle in one direction (.vertline.theta.vertline.) as fibers wound in the opposite direction (-.vertline.theta.vertline.), the fibers of each layer being buried in a matrix which adheres to these fibers. The fibers of the same layer and the associated matrix have a volume referenced Y, the parallel fibers of the same layer and the associated matrix having overall a modulus of elasticity in the natural direction of the fibers, referenced E, wherein said n layers of fibers comply as a whole with the following relationship:0.35.ltoreq.A.ltoreq.0.

Abstract: The tube, composed of a structural portion (1) of composite fibers encapsulated with thermosetting matrixes playing the part of a binder and obtained by filament winding, is provided with at least one inner coating (2) of a fibrous composite material impregnated with a thermoplastic binder, which is directly adjacent to the tubular portion formed by the structural portion (1) with the thermosetting binder.Application to oil production tubings.

Abstract: Fibers, which are substantially longitudinally profiled, are wound both around a cylindrical mandrel and a metallic double cone-shaped tip which is engaged onto said mandrel. Said fibers are turned back about studs distributed on a ring which is mounted on a threaded portion extending from the tip, whereupon said longitudinal fibers are binded thereto by means of circumferential fibers before the polymerization process of the tube has been completed. The composite tubes thus produced may be used in off-shore oil prospecting.

Abstract: The invention provides a method for forming a composite material tube connection.On a rubber skin 1 are wound inserts 3 and 4 which form the extra thick portions required for snap fitting of the tubes, of the male end piece and of the female end piece, on these inserts and on the current part of the tube fibers 5 are wound circumferentially, on the tube is fitted a sleeve 6 previously formed, on the female end piece are bound strips 7 also formed previously, and a stop heel 10 is formed on the male end piece by a new winding.