摘要 |
A screw extruder comprises a barrel (10) having a chamber (12) in which a screw (14) is mounted for rotation about an axis A. Sets of pins (22) project from the barrel into annular zones (24), (25) of the chamber (12), interrupting flights (26), (28), (30), (32) of the screw. The flights at either side of the, or each, annular zone (24) are displaced angularly relative to one another so that at either side of each annular zone (24) the flights are staggered. End portions of adjacent flights at either side of each annular zone (24) overlap. Material processed may have less temperature variation and improved homogeneity compared with material processed by previously known extruders. |