How to ensure the function of the screw barrel

2022.06.01
Working characteristics of conical screw barrel:
① The screw speed can be configured as stepless pressure and speed regulation.
② Linear guide injection instead of guide post injection, reduce friction during injection and improve injection accuracy (optional).
③ The screw and barrel are made of alloy material, quenched and tempered and desalinated to improve the wear resistance. The injection adopts the electronic ruler of Italian Jeffren, and the position control accuracy can be controlled within 0.1mm.
④ The 4-stage injection pressure and speed, and the 4-stage pressure-holding pressure and speed independent control are more conducive to the adjustment of the injection process.
⑤ Manual back pressure device (optional for CNC back pressure) can improve the plasticization, exhaust and density of plastic by screw. After feeding, a back pressure elimination device is added to prevent the plastic from flowing into the mold when the back pressure of the feeding is used in the production of products without the need for the loosening action to cause cold material.
Common methods of screw barrel cleaning:
(1) Use barrel cleaner
If the raw materials for injection products are frequently replaced or the plasticizing temperature range of the residual material in the barrel and the refueling material is quite different, in order to save raw materials and improve work efficiency, it is more economical to use a barrel cleaning agent. The cleaning agent is a kind of material similar to rubber material. It does not melt at high temperature in the barrel. It is in the form of softened micelle in the thread groove of the screw. get cleaned up.
(2) Using the material change ejection method
If the plasticizing temperature range of the new raw material to be replaced is higher than the plasticizing temperature range of the residual material in the barrel, the barrel and nozzle can be heated to the minimum plasticizing temperature of the new raw material, and then the new material is added and the air is continuously emptied. Inject until there is no residue in the barrel.
If the plasticizing temperature range of the residual material in the screw barrel is higher than the plasticizing temperature range of the material to be replaced, the barrel should be heated up to the plasticizing temperature range of the residual material in the barrel to remove the residual material. The nozzle material can be added later for cleaning, and the new material is put into production at the end. If the product requirements are high, the first few molds of the new material can be scrapped.