RESIN DEGRADATION PREVENTING STRUCTURE AND METHOD IN BREAKER PLATE DOWNSTREAM PART OF EXTRUDER

摘要

PROBLEM TO BE SOLVED: To prevent degradation of resin due to retention of the resin on the downstream side of a breaker plate.SOLUTION: A resin degradation preventing structure and method in the downstream part of a breaker plate of an extruder include: a breaker plate (5) provided in a downstream side (2b) of a cylinder (2) having a screw (3); a pipe line (4) provided in the downstream side (2b) of the cylinder (2); and a resin guide flow passage (6) having a tapered flow passage (7) communicating with an inner hole (2a) of the cylinder (2) formed in the pipe line (4). A taper angle (&thetas;) is set so that wall surface shear velocity in the tapered flow passage (7) is 5 secor more.