| 摘要 |
In a process for producing pourable spherical segment-shaped packing material bodies of plastic with a surface which is externally convex and internally concave, the plastic is introduced from a filling hopper through an opening into a bush surrounding the extruder screw. The plastic is plasticated and, because of the velocity difference prevailing over the melt cross-section, emerges from a die orifice with a curved surface. The plastic strand is cut off directly at the die orifice and still before a significant expansion has taken place. The plastic material is fed into a space between the extruder screw and a bush (28) provided with longitudinal grooves (35) in the material feed zone (13). This provides a possibility for some of the plastics granules to escape into the longitudinal grooves (35), resulting in an increased and more constant transport of material through the extruder. …<IMAGE>… |
