In Dalian extrusion, granular or powdery solid materials are added to the hopper of the extruder。 There is a heater outside the barrel of the extruder。 The heat generated by the heater is transmitted to the material in the barrel through heat conduction, and the temperature rises to reach the melting temperature。 The machine runs and the screw in the barrel rotates。
The material is conveyed forward。 During the movement, the material rubs and shears with the barrel, screw and material, which generates a lot of heat。 The material of Gaco is melted continuously by the heat conduction。 The melted material is continuously and steadily conveyed to the die (or die) with a certain shape。
Under the action of screw rotation, the loose solids are conveyed forward to the feeding section through the friction shearing action on the inner wall of the barrel and the surface of the screw, and compacted at the same time。 In the compression section, the depth of the screw groove becomes shallower and further compacted, while heating outside the barrel and friction shearing action between the screw and the inner wall of the barrel, the material temperature rises and begins to melt, and the compression section ends。
The homogenization section makes the material uniform, and extrudes the melt at constant temperature, quantity and pressure. The melt is formed at the back of the machine head and the product is shaped. The same brand of raw materials, found that the raw materials are not dry well, after re-drying and extrusion also have to clean the die. After changing the material, if the extrudate is not smooth, unstable and easy to break, the die head should be removed and cleaned up.