FIBER-REINFORCED COMPOSITE HOLLOW STRUCTURE, METHOD FOR PRODUCTION THEREOF, AND APPARTUS THEREFOR

摘要

Center cores are formed by extrusion-molding ABS resin which is a PS-based thermoplastic resin having a thermal deformation temperature of 106 DEG C. Seven pieces of the center cores, which are juxtaposed to each other in the horizontal direction, are supplied by a pultruder, and reinforcing long-fibers impregnated with an unsaturated polyester resin are allowed to pass through dispersion guides and squeezing nozzles, to thus squeezing-mold a fiber-reinforced composite hollow structure having FRP made legs. A final squeezing nozzle is disposed in a cross head die through a cooling jacket, and the hollow structure thus molded is allowed to pass therethrough to be covered with the ABS resin in a state in which the outer periphery of the hollow structure is heated. The hollow structure thus covered is subjected to cooled-sizing through a plurality of horizontal and vertical pairs of rollers, and then cured in a hot curing tank at a temperature of 95 DEG C. The surface covered with the ABS resin is subjected to a surface-treatment of imparting irregularities for giving an antislipping function to the surface. A thermoplastic resin-made protective cap is fitted to an end of the center core. The cap includes a planar plate-like portion having substantially the same shape as the sectional shape of the end of the composite hollow structure, and a claw-like projecting portion which projects from the plate-like portion and which expands towards its tip end. The projecting portion is separated in the peripheral direction. The apparatus for manufacturing a composite hollow structure has a plurality of pairs of rotatable and heat-resisting sizing rollers, each pair being mutually opposed on the upper and lower sides. The plurality of pairs of the sizing rollers are disposed in the pultruding direction while being gradually cooled in the order from those positioned on the upstream side to those positioned on the downstream side for sizing the softened outer layer covering the outer periphery of the intermediate layer.