Method for manufacturing an lft extrusion member
AssigneeNan Ya Plastics Corporation
InventorsTE-CHAO LIAO, HAN-CHING HSU, CHUN-LAI CHEN
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Abstract
An extruder and a long fiber thermoplastic (LFT) extrusion member manufactured thereby, and the extruder uses the LFT as a raw material to produce LFT extrusion members such as LFT sheets, pipes and profiles by a continuous extrusion molding process. The structural improvement of the extruder screw, including the screw body having three different thread groove deep sections, in sequence, a feed section, a compression section and a metering section, so that the LFT extrusion member produced by the extruder has high strength, high stiffness, high dimensional stability, low warpage and resistance to creep.
Claims6
A method for manufacturing a long fiber thermoplastic (LFT) extrusion member by an extruder, comprising:
- preparing a raw material which includes 33.3 to 75% by weight of a thermoplastic resin and 25 to 67.7% by weight of long fiber thermoplastic masterbatch;
- melting the raw material at a temperature of a first zone ranging from 180 to 260° C., a temperature of a second zone ranging from 200 to 260° C., a temperature of a third zone ranging from 210 to 285° C., a temperature of a fourth zone ranging from 220 to 290° C., and a temperature of a die head ranging from 240 to 310° C.;
- extruding the raw material by an extruder with a draw speed from 0.3 m/min to 2.0 m/min to form the LFT extrusion member through continuous pultrusion process, wherein the extruder includes a screw and extrusion conditions includes:
- wherein a total length of the screw is L and a diameter is D, and an L/D ratio is between 20 to 26;
- wherein a shaft of the screw includes three sections having different thread groove depths, which are sequentially a feed section, a compression section and a metering section, wherein a length of the feed section is L1, a length of the compression section is L2, a length of the metering section is L3, wherein L1+L2+L3=L;
- wherein a length of the feed section is 0.40-0.50 times the total length of the screw, a length of the compression section is 0.30-0.40 times the total length of the screw, and a length of the metering section is 0.10-0.20 times the total length of the screw;
- wherein a thread groove depth of the feed section is d1, a thread groove depth of the compression section is d2, and a thread groove depth of the metering section is d3, wherein 4 mm≤d1≤7 mm, and d3<d2<d1;
- wherein a compression ratio of the screw is d1/d3, and a ratio of d1/d3 is between 2.0 and 4.0;
- and
- wherein a temperature of the feed section of the screw spans the first zone and the second zone, a temperature of the compression section of the screw spans the second zone and the third zone, and a temperature of the metering section of the screw is located in the fourth zone.
Dependencies are inferred from the claim text.