1: plasticizing

Through the action of barrel temperature and screw, the material is transformed into a homogeneous continuous melt with a certain fluidity.

Two: molding

Due to the flow of the uniform melt, the screw enters the machine head through the perforated plate due to the rotation of the screw, and is formed into a parison with a certain shape according to the die core rod.

Three: Cooling

That is, under the effect of extrusion pressure and traction, the parison is shaped by vacuum cooling to form a product with certain strength, stiffness and dimensional accuracy.

2-4 granulation process

    The granulation process is an operation process in which the resin and various additives are calculated, mixed, and plasticized to form compact spheres, cylinders, and cubes that are easy to form. There are many ways to granulate, such as:

Resin + Auxiliary → Weighing → Mixing → Extrusion → Round Bar → Cooling → Line Pelletizer Pelletizer

Extrusion granulation operation is continuous, closed, easy to filter out impurities, high output, low labor intensity, clean environment and low noise, but the quality of plasticizing is not as easy to control as the tableting method.

2-5 Control of extrusion process

Extrusion process control includes control of molding temperature, extrusion speed, vacuum dehumidification, vacuum speed, and vacuum cooling setting.

1. Control of temperature

Extrusion temperature is a necessary condition to promote the plasticization of the molding material and the flow of the plastic melt. It directly affects the rheological state of the material during the entire processing process. It is very important for the plasticization of plastics and the production and quality of profile Meaning.

During the entire processing process, the material must achieve the transition from glassy state to high elastic state to viscous flow state, and the temperature control of each section is also different.