| 摘要 |
1,094,691. Extruding reinforced tubes. J. BICHL. Feb. 3, 1965 [Feb. 11, 1964], No, 4627/65. Heading B5A. [Also in Division F2] Tubes or solid sections reinforced with substantially continuous longitudinal reinforcements 15, Fig. 4, and with filamentary reinforcements 16 which are substantially transversely orientated, are formed by an extrusion process wherein plastics material containing the filamentary reinforcing material is fed by means of a screw or ram impeller from a conduit 11 through an annular channel 12 to an elongated die passageway 17, Fig. 1, the direction of entry of the material being normal to the passageway 17 through annulus 13, with the material emerging adjacent guides 14 through which the continuous reinforcements are fed. During movement through channel 12 the filamentary material is substantially orientated in the direction of flow, which orientation is maintained so that the material enters the die passageway 17 substantially transversely to the longitudinal axis of the die. The continuous reinforcements (15), Fig. 5 (not shown), may be distributed in one or more coaxial layers. The formation of a tube having a ridged rectangular cross-section is described, Figs. 2 and 3 (not shown), and so also is a plant which incorporates a doubleacting ram (23), Fig. 6 (not shown), a saw 30, a cooling bed 31 and rollers 32. Reinforcing materials mentioned include asbestos, glass fibre, glass wool, slag wool, polyamides, metal wire or strip. Preferably the continuous longitudinal reinforcements are prestressed to apply a back-pressure to the plastics material. The filamentary material may be impregnated with A- or B-stage resins which resins may also be used as the plastics material. Heating coils 27, 28 and (29), Fig. 2 (not shown), are provided. |
