Add powder or granular material, butyl ester, old material and calcium powder into the hopper of the extruder, and use the high-speed mixing barrel for continuous mixing. The evenly stirred plastic raw materials are extruded from the porous die or metal mesh with the high extrusion pressure of the extruder. Usually, after the material is put into the hopper, the screw is used to extrude the material. After using the frequency converter speed regulation technology, the pressure can be controlled so that the appropriate linear speed can be selected.
Extrusion molding is the continuous molding of polymer melt through a certain shape die under the extrusion of extruder screw. The product is a continuous profile with a constant cross-section shape. Extrusion equipment includes screw extruder and plunger extruder. The former is continuous extrusion and the latter is intermittent extrusion. Screw extruders can be divided into single screw extruders, twin-screw extruders, exhaust extruders and multi screw extruders. Among them, single screw extruders are more and more basic in production. In recent years, twin-screw extruder has developed rapidly, and its application is becoming more and more extensive.
Plastic extruders can be divided into cold feed plastic extruders and hot feed plastic extruders according to the classification of feeding methods. The difference between these two kinds of plastic extruders lies in whether the feeding system of the equipment is a forced feeding system. During installation, pay attention to adjust the center line of the extruder head to be vertical and horizontal, and the center of the traction | roll shall not deviate.
The feeding mouth of the cold feed plastic extruder is equipped with a forced feeding roller. When the equipment temperature rises to the temperature we need, we can feed in the feeding mouth of the plastic extruder. Feed the raw material through the forced feeding port to keep the screw barrel pressure of the extruder at a constant state, especially after the pressure of the die head of the extruder is constant, it is uniform and stable during extrusion, and the product size is uniform.
The feeding system of the hot feed plastic extruder is directly driven by the screw, which is cheap and saves costs. However, for the extruder used for extrusion molding, this kind of plastic extruder is not suitable for extruding finished products.
In the process of starting and heating the plastic extruder, the temperatures of several sections are turned on at the same time to start heating. Of course, this method is also commonly used. However, after the screw temperature reaches a certain index, the temperature of the die head often does not reach the steel in the die head, which is relatively thick and has a large area). Therefore, in this case, the screw is generally insulated, Then start the operation after the temperature of the die head slowly rises to the set temperature. This method is the first power on.
