METHOD OF STRIPING OF VOLUME PREFORMS Russian patent published in 2020 - IPC B29C70/04 

FIELD: technological processes.

SUBSTANCE: invention relates to the technology of making preforms of articles from polymer composite materials (PCM) - workpieces based on reinforcing fibres. Invention can be used in basic industries, such as aircraft engineering, space industry, power engineering, shipbuilding and automotive industry, for production of parts and their components from PCM, which can withstand extreme mechanical loads. Technical result of disclosed solution consists in elimination of deformation and damages of main reinforcing thread, as well as substrate due to non-use of sewing fixing thread, according to the proposed scheme of layer-by-layer strip of volumetric preforms and selection of substrate material, which leads to broader technological capabilities of the process of making fibrous blanks, and also selectively affects strength properties of target articles and their components from PCM. Proposed method consists in laying and fixing of main reinforcing thread on fixed substrate with subsequent build-up of layers of three-dimensional structure according to TFP technology on programmed embroidery machine. Fixation of the main thread is carried out by needle piercing with the substrate thread on the basis of the water-washing nonwoven with the clamp of the formed loop due to friction with the substrate material and further movement in the rectilinear direction of the stowing head with the needle to the next point specified by the program. In case of curved direction of laying in bending point or maximum stress, main thread loop is fixed additionally with suture filament by means of second needle operating in automatic mode synchronously with first, wherein in case of layers up to preset thickness of preform the perimeter of trajectory of every next layer of the main thread should exceed the previous one. Reinforcing threads used are carbon fibres, including in the form of roving, and the aramide fibres are used as the fixing threads.

EFFECT: proposed scheme of layers laying allows reinforcing preforms as straight and level as possible - without bends and waves, with threads, which allows to achieve the best characteristics of reinforcing filler when testing final products for bending and stretching.

4 cl, 6 dwg