METHOD FOR MANUFACTURE OF NOZZLE INSERT Russian patent published in 1996 - IPC

FIELD: manufacture of nozzle inserts. SUBSTANCE: fibrous phenolic plastic loaded into matrix of mold is compacted to form horizontal surface of softened material, placed successively onto which are rings cut out of carbon fabric prepreg impregnated with phenol-formaldehyde binder. The number of fabric rings is determined by the formula N=(0.3-6) mm/sigma, where sigma is the thickness of pressed ring within the range of 0.1-0.5 mm, inner diameter dl of lower rings 1-4 is (0.5-0.6)D, inner diameter d3 of upper rings 1-2 corresponds to the minimum diameter of cross-section of the punch which molds the nozzle channel having cylindrical lower part and conical expanding upward upper part. Inner diameter d2 of the other rings is established equal to (0.4dl-0.6d3)-(0.6dl-0.4d3). Outer diameter D of all rings equals the diameter of the maximum cross-section of the punch molding surface. Placed into matrix material is pressed by moving the heated punch and held under pressure up to curing. EFFECT: higher efficiency. 1 dwg, 1 tbl