Dalian extrusion moulding transfers the heat generated by heater to the material in the barrel through heat conduction, and the temperature rises to reach the melting temperature。 When the machine runs, the screw in the barrel rotates, and the material is conveyed forward。 During the movement, the material rubs and shears with the barrel, the screw and the material and the material, which generates a lot of heat。 Together with the heat conduction, the material of Gaco is melted continuously and stably, and the molten material is conveyed to a certain shape continuously and steadily。 In the head (or die) of the shape。
Select the extruder, die and die, as well as the corresponding auxiliary devices such as shaping and traction, and then determine the extrusion process conditions such as screw speed, head pressure, material temperature, shaping temperature, traction speed and so on. In the extrusion process, materials are usually processed, but the method of setting is different. Flat products whose length is much larger than width are called sheets; thin films whose thickness is less than 0.25 mm are called films.
If the film from the flat die is cooled by a cooling drum with a very smooth surface, the flat film can be made。 This method is also called extrusion casting method。 This is a common method of making polypropylene film。 If the flat film is fed into the stretcher and stretched 4-10 times both vertically and horizontally (or lengthwise stretching first, then horizontally stretching), the biaxially oriented film can be obtained。
The outer wall of the brick is thick on one side and thin on the other. The main reason is that the machine mouth, core, mud cylinder and spiral reamer are not in the same center, and should be corrected. Secondly, the mud strips move forward in zigzag shape, and the concave areas are sometimes pulled out. The main reason is that the top of the main blade and the secondary blade of the spiral reamer in the extruder of brick machine are not uniform, or the secondary blade is worn seriously.
The main and secondary blades of the spiral reamer should be repaired or replaced. Mainly the middle of the mud extruder speed. One is to lengthen the middle core of the core tool, or to set a mud blocking pipe on the core rod behind the middle core head to reduce the mud input in the middle; the other is to increase the radian of the four corners of the feed end of the machine inlet to expand the mud input around it.