| 摘要 |
1. Device for the forming of tubes, hoses, hollow, shaped pieces and the like (2) in plastic material, particularly in polypropylene, obtained by extrusion and having a wall provided with hollow channels (13, 14) of any cross-section, parallel to the longitudinal axis (17) of the said extruded products (2), these channels (13, 14) being obtained to the outlet of the extrusion head (1) and maintained open during the step of cooling and having, distributed on the internal surface of the extrusion head (1), satellite punches (6, 7) disposed between the central punch (4) and the die (3) and jointing the calibrators (18, 19) maintaining the channels (13, 14) open since the outlet of the product of the extrusion head (1) until the total hardening of the said extruded products (2), characterized in that the satellite calibrators (18, 19) are flexible elements suiting to the deformations that the extruded products undergo between the outlet edge of the extrusion head (1) and the inlet edge (1067) of the conformator (1059). |
