| 摘要 |
PURPOSE:To enable the extrusion of long items of thermosetting resin successively, stably and with excellent productivity, by forming these items in the smooth part of a screw of an extruder in such a degree that they can retain their formed shapes after the extrusion. CONSTITUTION:The length of the smooth part 4 in the tip of a screw 8 can be selected properly from a range of 1D-15D (D: the diameter of the screw), or preferably 2D-7D. When the length of the smooth part 4 is smaller than 1D, a deformation occurs in a formd item obtained after the extrusion, and thus it is difficult to obtain successively excellent formed articles. When the length of the smooth part 4 is larger than 15D, a forming pressure turns large, and thus it is not practical from a viewpoint of a mechanical strength after the extrusion as well. Moreover, the surface of the screw 8 in a metering part 3 and/or the whole or a part of the inner surface of a cylinder 10 is inclined at some angle to the axial direction of the screw. This inclinaion enables the reduction of the frictional resistance between the screw 8 in the metering part 3 and the cylinder 10 and resin, as well as an improvement in the effect of compression contact with the resin. |
