A production device for extruded film

Abstract

Disclosed is a manufacturing device for extruding a thin film. The device is used for processing of annular downward extrusion of a water-cooling cast thin film. The device comprises an extrusion port die for forming a plastic film bubble, a water inlet ring for cooling and forming a film bubble, a water return ring for recycling cooling water, a guide structure for pressing a film bubble into a folded film, and a driving mechanism for continuous forming of a blown film, wherein the foregoing parts are sequentially arranged from top down. A vacuum film bubble stabilizer used for forming a certain degree of vacuum on a part of an annular outer surface of a film bubble is provided between the water return ring and the guide structure, a cavity is provided in the vacuum film bubble stabilizer, meshes in communication with the cavity are provided on an inner annular surface of the vacuum film bubble stabilizer, an exhaust tube in communication with the cavity is provided on an annular wall of the vacuum film bubble stabilizer, and the exhaust tube is located on an external end of the annular wall and is connected with a vacuum pump. Due to the presence of the vacuum film bubble stabilizer in the device, the film bubble has good stability, the processing operation is simple and convenient, the quality of a thin film is improved, and the materials required for processing is reduced.

Description

technical field [0001] The invention relates to a production device for extruding films, in particular to a production device for processing ring-shaped downward extruded water-cooled casting films. The production device can improve film quality and reduce material loss. Background technique [0002] The thickness of the plastic film is generally between 12.5 and 300 microns, among which the thick film is greater than 200 microns, the middle film is between 75 and 200 microns, and the thin film is between 12.5 and 75 microns. Traditional plastic film production methods include tape casting and blown film processing. [0003] The existing cast film processing technology mainly refers to the extrusion melt casting process. Extrusion melt casting process is to obtain flat extrusion film by casting plastic melt and then quenching. The process flow is: extruder extruding - T-die casting - air knife - 1# cooling roll ——2# cooling roll—corona treatment—waste cutting—coiling. [...

AI Technical Summary

Problems solved by technology

However, in order to maintain a certain cooling rate, the position of the water ring must be close to the die, so the water ring cannot play the role of stabilizing the film bubble

At the same time, when the bubble continues to run downwards after leaving the water ring, the internal pressure of the bubble gradually decreases due to the high temperature of the gas in the upper part and the low temperature of the gas in the lower part, resulting in a low radial pulling force for the outward expansion of the bubble, thus As a result, it is difficult to wind and guide the lower end of the film bubble, which brings about a series of problems such as unstable product quality of the film, increased material loss, and even shutdown of production in severe cases.

[0006] So far there is no reliable bubble stabilizing mechanism, which makes the circular downward extrusion water-cooled cast film processing technology more effective and easy to promote

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