| 摘要 |
The barrel (2) of the extruder is equipped, at its downstream end, with a cooling jacket (14) through which a system of cooling tubes (15) runs. The screw (10) includes, in the zone located in the region of the cooling jacket (14), an end-fitting (13) provided with one or more flights elongated in the axial direction. This or these flights may follow lines in the form of a helix or may be straight and parallel to the axis. The diameter of the front edge, bounded between the crestal face of each flight and its front surface oriented in the direction of rotation of the screw, is adjusted to the diameter of the internal face of the barrel so as to ensure that the plastic film, which is formed on the barrel because of the cooling, is removed by a scraping action. <IMAGE>
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