GB1391844A - Melt-spinning device for synthetic fibres - Google Patents

Abstract

1391844 Melt-spinning apparatus DU PONT OF CANADA Ltd 13 April 1972 [16 April 1971] 17148/72 Heading B5B In apparatus for melt-spinning filaments, molten polymer is supplied from a common source through transport means to a plurality of spinning packs, at least some of the spinning packs and transport means being mounted in or insulated vessel and heated in a common environment by heated vapour. As shown in Fig. 1 polymer is supplied from extruder 10 via pump 14 to transfer line 16 and thence to the independent spinning positions 17. Vessel 13 surrounds the transfer line 16 and spinning positions 17. As shown in transverse section in Fig. 5, transfer line 16 connects with manifold 41 and so with splitters 42 which distribute the molten polymer via feed lines 43 to the spinning packs 52. The manifold and transfer line assembly are kept at a constant temperature inside the insulated vessel 13 by vapour from the liquid heat bath 45. The spun filaments may pass down quench chimneys 27 to draw-twisting and finishing apparatus. Polyhexamethylene adipamide is given as an example of a polymer to be used in this apparatus. In Fig. 3 three inverters 37 are shown. These invert the flow of the molten polymer so that the outer one-third of the flow is directed into the centre of the pipe at each inverter. After three such inversions the "cross-section" of the flow is substantially the same as at the outset, but the lag covered by laminar flow is avoided and the polymer has substantially the same thermal history across this section. The same thermal history is maintained by careful positioning of the splitters, which remove the slower moving edge portion at the first, and the central feeder, portion at the last. This ensures that the polymer reaching each spinneret has had the same residence time.