GB1019517A - Method of and apparatus for melt spinning synthetic organic linear high molecular weight polymers - Google Patents

Abstract

1,019,517. Melt spinning synthetic filaments. CHEMIEFASERWERK SCHWARZO WILHELM PIECK VEB. Nov. 15, 1962, No. 43269/62. Heading B5B. In the process of melt spinning synthetic filaments in which the molten filaments from the spinneret are cooled and solidified by passing them in a generally vertical downward direction through a spinning cell in which a non- turbulent stream of a cooling gas or vapour is directed laterally on to the filaments, the stream of gas or vapour has a temperature of 15‹ to 30‹ C., and a relative humidity of 50 to 90% and the stream of gas or vapour impinging on the filaments is inclined downwardly from the horizontal in the direction of its flow at an angle of between 10 and 30 degrees. As illustrated in Fig. 1 (not shown) an apparatus for cooling and solidifying the filaments according to the invention comprises a three-way valve 1 for controlling the rate of flow of the gaseous cooling medium, e.g. air, into the blow box or plenum chamber 4 through an entry tube 2 and a filter or diffuser system 3. The wall between the blow box 4 and the spinning cell 11 through which the melt spun filaments travel downwards and in which they are cooled and solidified comprises an assembly of superimposed layers of fine wire gauze or perforated metal sheets 5 and a honeycomb-like nest of short tubes 6 through which the cooling medium from the blow box 4 is impelled into the filament spinning chamber in a diffused but substantially straight line flow free from turbulence so that the cooling gas contacts laterally the downward travelling streams of polymer. The direction of the gas flow is downwardly inclined from the horizontal at an angle to the path of filament travel, the path of the cooling medium being, for example, inclined at an angle of 15 to 25 degrees to the horizontal. The spinning chamber comprises two solid vertical side walls 7 (Fig. 2, not shown), which are curved in such a manner as to contribute to the non-turbulence of the flow of cooling gas. The side-walls 7 converge towards the front of the spinning chamber and the vertical opening between them at the front of the chamber is divided by a closure member 8 of triangular or knife-edge horizontal crosssection into two narrow vertical outlet slots whose width can be adjusted by means of the member 8. The filaments from the spinneret enter and leave the spinning chamber through the ducts 9 and 10, respectively, the joints between these ducts and the spinning chamber being air-tight.