METHOD FOR MANUFACTURING FLAT-FORM FIBROUS WORKPIECES Russian patent published in 2020 - IPC B29C70/24 B29C70/28 B29C70/34 B29B15/08 D04H3/04 D04H3/10 

FIELD: manufacturing technology.

SUBSTANCE: invention relates to production of preforms of articles from polymer composite materials (PCM) – blanks based on reinforcing fibers. 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. Method for manufacturing flat-form fibrous workpieces consists in creation of three-dimensional structure from layers of reinforcing fibers by means of automated directed sewing on according to TFP-technology of the first layer to substrate, fixed with subsequent layers by fixing threads of zigzag line, and further impregnation of formed carcass with binder. In the method, density of laying layers of reinforcing fibers, which characterizes distance between layers, is 2.75–2.90 mm or for control program by embroidery equipment, on which method is realized, – 55–58 standard units, with 1 standard unit = 0.05 mm. Length of the zigzag stitch of the fixing thread piercing thread makes 5–7 mm with the stitch width of 5 mm. Formation of blank layers is carried out with orientation of reinforcing fibers [0°, 90°], which are alternated in pairs when preset thickness of preform is set. Method also employs a detachable wafer of a water-soluble airfibre-type material.

EFFECT: technical result achieved when using the method under the invention consists in optimization of the technological process due to use of preforms of PCM products with the specified parameters of the blank layers sewing on: stacking density and zigzag stitch length, which ensure maximum rate of impregnation of structural frame and quality of formed composite.

5 cl, 2 dwg, 2 tbl