| 摘要 |
<p>For the extrusion of a composite strip formed of two kinds of material two screw extruders are arranged one above the other. The lower extruder is horizontal while the upper extruder is inclined downwardly so that both extruders extrude through a common extruderhead. The extruderhead comprises a fixed central portion having converging opposite faces and hinged upper and lower jaws on opposite sides of the central portion. Interchangeable insert plates are secured on opposite sides of the central portion of the extruderhead and on the inner faces of the upper and lower jaws. The insert plates are provided with cooperating channels to define the shape of the extruded strips and the portions of the strips which are formed, respectively, of material from the upper and lower extruders. The upper and lower jaws are movable hydraulically between a closed position for extrusion and an open position for cleaning and for changing the insert plates so that different shapes can be extruded and selected portions of the extruded shapes can be formed of different materials.</p> |
