| 摘要 |
An extruder includes a barrel connected by a cooling device to a die. The cooling device comprises three shells, one within the other to define concentric outer and intermediate passages and a central passage. Molten working material is passed through the intermediate passage and coolant is passed through the outer passage and the central passage. Working material is fed to the intermediate passage via a tubular inlet having apertures through which the material enters the passage and leaves it via an outlet tube also having apertures. The relative size of the apertures in the inlet and outlet tubes is such as to ensure hydraulic balance of the working material and smooth flow. Efficient and uniform cooling is provided. |
