Screw And Barrel Is An Important Part Of The Injection Molding Machine
All of these procedures are done by the rotation of the screw in the barrel. In the rotation of the screw, the plastic for the barrel wall, the bottom of the groove, the edge of the roll and the plastic and plastic will have a friction between the friction and mutual movement, the plastic forward is the result of this combination of movement, and friction generated heat Also absorbed is used to raise the plastic temperature to melt the plastic. The structure of the screw will directly affect the extent of these effects. In order to improve the quality of plastic can be screwed into a separate screw, barrier screw or split type screw.
Screw and Barrel Manufacturing barrel, the current domestic commonly used materials are 45,40Cr and 38CrMoAIA. Imported extruder in the barrel of the manufacturing materials, commonly used alloy steel 34CrAINi and CrMoV9. The yield strength of this material is about 900 MPa. After nitriding treatment, the hardness of more than 1000HV, both wear-resistant and good corrosion resistance. Tungsten carbide alloy + nickel alloy cylinder, the use of Material High quality alloy just as the substrate, the hole casting the alloy, to improve the wear resistance of the barrel, Corrosion resistance.
1, do not start the machine when the cylinder screw does not reach the pre-set temperature.
2, to prevent the metal debris and debris fall into the hopper, if the processing of recycled materials, need to add a magnetic hopper to prevent iron and other into the barrel.
3, the use of salivation when the barrel to determine the plastic completely melted, so as not to damage the screw when the drive parts damage.
4, the use of new plastic, the material should be more than the residue clean.
5, when the molten plastic temperature is normal but continue to find injection products appear black spots or discoloration, should check the screw over plastic head, over the rubber ring, glue meson wear. The
6, product injection molding, try to make the material evenly plastic to reduce the screw to withstand the transmission torque, improve its useful life.
Screw and Barrel The nozzle is the transition between the barrel and the mold. At the time of injection, the melt in the barrel is driven by the screw and injected into the mold with high pressure and rapid movement through the nozzle. Therefore, the structure of the nozzle, the size of the nozzle and the manufacturing accuracy will affect the melt pressure loss, the temperature rise and fall, the range of distance, the role of the role of complement and whether the "salivation" phenomenon.