阅读说明：本技术 一种提高pvb胶片挤出机产量的方法 (Method for improving output of PVB film extruder ) 是由 沈小罡 佟春涛 童祎 李礼 伊新华 翟士豹 项小敏 于 2019-10-10 设计创作，主要内容包括：本发明公开了一种提高PVB胶片挤出机产量的方法,是通过增加PVB胶片挤出机螺杆的有效长度,以改变螺杆长径比,从而提高PVB胶片挤出机产量。本发明的方法,可将PVB胶片挤出机产量提高20％～50％,大大地提高了挤出机生产效率、节约了成本,且通过本发明的方法还可以显著提高PVB胶片的塑化质量。(The invention discloses a method for improving the output of a PVB film extruder, which changes the length-diameter ratio of a screw by increasing the effective length of the screw of the PVB film extruder so as to improve the output of the PVB film extruder. The method can improve the output of the PVB film extruder by 20-50 percent, greatly improve the production efficiency of the extruder and save the cost, and can also obviously improve the plasticizing quality of the PVB film.)

1. A method for improving the output of a PVB film extruder is characterized in that: through the effective length who increases PVB film extruder screw rod to change screw rod draw ratio, thereby improve PVB film extruder output.

2. The process of claim 1 for increasing the throughput of a PVB film extruder, wherein: the effective length of a screw of a PVB film extruder is increased at the same time in a conveying section and a melting section.

3. The process of claim 1 for increasing the throughput of a PVB film extruder, wherein: the ratio of the effective length of the screw with the conveying section increased to the effective length of the screw with the melting section increased was 1: 1.

4. A process for increasing the throughput of a PVB film extruder as set forth in claim 1 or claim 2, wherein: the PVB film extruder adopts the parallel twin-screw structure of syntropy meshing, the twin-screw of PVB film extruder adopts combination formula screw rod.

5. A process for increasing the throughput of a PVB film extruder as set forth in claim 1 or claim 2, wherein: the length-diameter ratio of the changed screw is 42-50.

6. A process for increasing the throughput of a PVB film extruder as set forth in claim 1 or claim 2, wherein: a new extruder barrel is additionally arranged in a corresponding screw rod growth area, and a conveying element and a shearing element are additionally arranged at the same time.

7. The process of claim 6 wherein the PVB film extruder throughput is increased by: the temperature of the newly added extruder barrel is controlled to be 120-190 ℃; the conveying element is 64/64, 72/72 and 96/96 or a combination of several of the conveying elements, and the shearing element is 45 °/5/56, 45 °/5/64, 45 °/5/72, 45 °/5/96, 90 °/5/56, 90 °/5/64, 90 °/5/72 and 90 °/5/96 or a combination of several of the shearing elements.

8. A process for increasing the throughput of a PVB film extruder as set forth in claim 1 or claim 2, wherein: the PVB film extruder comprises the following process parameters: the rotation speed of the main machine is 500-1400 rmp, the current of the main machine is 140-330A, and the rotation speed of the screw is 80-320 rmp.

Technical Field

The invention belongs to the technical field of PVB film production equipment, and particularly relates to a method for improving the output of a PVB film extruder.

Background

A PVB film (polyvinyl butyral resin film), also called PVB film, is widely used for safety glass because of its excellent properties such as transparency, light resistance, heat resistance, sound insulation, softness, antifogging, no hardening at low temperature, and good adhesion to glass and metal. Up to now, safety glass has been widely used, and is widely used in the fields of aircraft manufacturing, bank counters, building industry, solar cell films and the like besides small automobiles.

The most central equipment in the production of PVB film is the extruder section. At present, a PVB film extruder mainly adopts a double-screw structure, has the characteristics of good charging performance, mixing plasticizing performance, exhaust performance, extrusion stability and the like, and is widely applied to the forming processing of extruded products. The major factor affecting the performance of twin screw extruders is the length to diameter (L/D) ratio of the screws, i.e., the ratio of the effective length to the diameter of the working portion of the screw. In general, the length-diameter ratio of a screw can represent the plasticizing capacity of the screw, while different length-diameter ratios affect the plasticizing effect. When the length-diameter ratio of the screw of the extruder is controlled within a proper range, the length-diameter ratio is increased, the retention time and the plasticizing time of the materials in the extruder can be prolonged, the mixing uniformity of the materials is increased, the plasticizing quality is improved, the counter flow and the leakage flow during extrusion are reduced, and the production capacity and the product quality of the extruder are improved. However, when the length-diameter ratio of the screw is too large, the difficulty in processing, manufacturing, assembling, using and maintaining the screw is increased, the screw is easy to bend and deform, the gap between the screw and the machine barrel is uneven, the power consumption of the extruder is increased, even the scraping and grinding phenomena are generated, and the yield is reduced due to too long retention time of materials in the extruder; when the length-diameter ratio is too small, the mixing and plasticizing of materials are not facilitated, and the yield and the product quality of the extruder are influenced.

CN109476043A discloses enhancing the mixing and plasticizing properties of a resin material by mounting a kneading disc on an extruder screw, the kneading disc having an improved mixing function for the resin material in the screw rotation direction. CN103770310B introduces a grooved barrel extruder, which realizes high-speed and high-efficiency melting and plasticizing of materials and obtains higher extrusion yield by designing the barrel of the extruder. Although the methods can effectively melt and plasticize materials in the extruder and improve the plasticizing quality and yield, the methods are more complicated, time-consuming and labor-consuming when cleaning and maintaining the cylinder, the kneading element and the extruder. In addition, in the production process, the friction between the materials and the kneading disc and the grooved machine barrel can be increased, the resistance of the movement of the materials is increased, the kneading elements and the machine barrel are abraded, the replacement period of the kneading elements and the machine barrel is short, and excessive heat generated by the friction can consume a large amount of cooling water, so that the production cost is increased.

Disclosure of Invention

In order to solve the problems of the prior art, the invention aims to provide a method for improving the output of a PVB film extruder, which aims to improve the production capacity of the extruder by changing the effective length of a screw and controlling the length-diameter ratio of the screw within a proper range.

In order to achieve the purpose, the invention adopts the following technical scheme.

The invention discloses a method for improving the output of a PVB film extruder, which is characterized by comprising the following steps: through the effective length who increases PVB film extruder screw rod to change screw rod draw ratio, thereby improve PVB film extruder output.

Further, it is desirable to increase the effective length of the PVB film extruder screw at the same time in the conveying section and the melting section.

Further, the ratio of the effective length of the screw with the conveying section increased to the effective length of the screw with the melting section increased was 1: 1.

Further, PVB film extruder adopts the parallel twin-screw structure of syntropy meshing, the twin-screw of PVB film extruder adopts combination formula screw rod.

Furthermore, the length-diameter ratio of the changed screw is 42-50, and the length-diameter ratio of the changed screw is 32-40 before changing.

Furthermore, a new extruder barrel is additionally arranged in the corresponding screw increasing area, and a conveying element and a shearing element are additionally arranged at the same time.

Further, the temperature of the newly added extruder barrel is controlled to be 120-190 ℃; the conveying element is 64/64, 72/72 and 96/96 or a combination of several of the conveying elements, and the shearing element is 45 °/5/56, 45 °/5/64, 45 °/5/72, 45 °/5/96, 90 °/5/56, 90 °/5/64, 90 °/5/72 and 90 °/5/96 or a combination of several of the shearing elements.

Further, the process parameters of the PVB film extruder are controlled as follows: the rotation speed of the main machine is 500-1400 rmp, the current of the main machine is 140-330A, and the rotation speed of the screw is 80-320 rmp.

Compared with the prior art, the invention has the technical effects that:

the method can improve the output of the PVB film extruder by 20-50 percent, greatly improve the production efficiency of the extruder and save the cost, and can also obviously improve the plasticizing quality of the PVB film.

Detailed Description

The following examples are given for the detailed implementation and specific operation of the present invention, but the scope of the present invention is not limited to the following examples.

Comparative example 1

The specification of the PVB film produced by the method is 0.76mm, the model of a PVB film extruder used for production is 95B, and the length-diameter ratio of the PVB film extruder is 40: 1. During production, the rotating speed of the extruder host is 500rmp, the host current is 140A, and the rotating speed of the screw is 120 rmp.

The yield of the PVB film of the comparative example is 380kg/h, and the performance indexes of the obtained PVB film are shown in the table 1.