摘要 |
1,042,758. Melt-spinning. BARMER MASCHINENFABRIK A.G. Nov. 6, 1963 [Aug. 3, 1963], No. 43856/63. Heading B5B. In a spinning extruder for melting synthetic thermoplastic material, and extruding the melt through spinnerets wherein a spinning pump between the extruder screw and the spinneret, and directly in front of the spinneret, acts as a metering means, the length of the metering zone is at least 12 times the diameter of the screw of the extruder in the metering zone, and the thread depth of the screw on the metering zone is at least 3.5% of the screw diameter. The simultaneous lengthening of the metering zone and increase of screw thread depth eliminates pressure variations in the melt and allows the spinning of uniform filaments with titre deviation less than 1%. Optimum effects are obtained using an extruder screw of total length 24 diameters, of which 12 are in the metering zone the thread depth being 4-5% of the screw diameter.
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