SU138016A1 - Apparatus for continuous production of a melt pipe from a thermoplastic melt - Google Patents

Description

Devices for continuous melt-pipe production from a melt of a thermoplastic are known, consisting of a melting crucible having a hole in the center for the passage of forced air, a spinneret, a water-cooled calibrating device and take-up rolls.

The proposed device, in comparison with the known ones, makes it possible to manufacture films in the form of a tube, for example, of polyethylene terephthalate, prevents the formable film from sticking to the walls of the sizing device, helps to obtain films from a very liquid melt with a viscosity of the order of a thousand poises transition from solid to liquid. For this purpose, the calibrating device is made in the form of two coaxially arranged cylinders, having an annular bottom at the bottom and a coolant supply spout.

The drawing schematically shows an apparatus for continuously producing a film in the form of a pipe from a melt of a thermoplastic.

The set of devices includes: axial fan /, forcing air through the diffuser 2 into the opening of the melting crucible 5; die 4 (ring); a calibration device consisting of two coaxially arranged vertical cylinders 5 and 5 with an annular bottom 7; paired take-up metal rolls 5 and 9, rotating synchronously; collection 10 for coolant (water).

Water is evenly supplied through the connector 11 into the annular cavity between the cylinders 5 w. 6, flows over the upper edge of the cylinder 6 and flows down over its entire inner surface, wets the take-up rollers and drains from the collector 10 into the sewer. The melt of a thermoplastic (polyethylene terephthalate) through a filter is fed into ring filler no. 138016-2 ru. 4. After a steady flow of the melt is established over the entire ring gap of the spinneret, a fan is turned on, the speed of which is gradually increased by means of a rheostat. The tube-like film exiting the spinneret begins to inflate with injected air. Blowing air is installed so that the melt pipe from the thermoplastic at the upper edge of the cylinder 6 has a diameter close in magnitude to the internal diameter of this cylinder. The thermoplastic melt pipe touches the water film at the level of the upper edge of the inner cylinder simultaneously over the entire cross section, quickly solidifies and passes down to the take-up rolls. A cold film in the form of a tube is drawn out of the calibrating device by means of the take-up rolls, the diameter of which in the process of its manufacture is controlled by varying the rotational speed of the take-up rolls.

Subject invention

Apparatus for the continuous manufacture of a tube film; a melt of a thermoplastic, for example, of polyethylene terephthalate, consisting of a melting crucible having a hole in the center for the passage of forced air and under which a die is successively mounted, a water-cooled calibrating device, characterized in that, in order to prevent the forming film from sticking to the wall of the calibrating device, it is made in the form of two coaxially arranged vertical cylinders having an annular bottom in the lower part and a fitting for supplying a cooling fluid.