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How to disassemble and maintain the double alloy screw nozzle of the injection molding machine?

Update:Dec 18,2020

The disassembly and maintenance of the double alloy screw nozzle of the injection molding machine has been a problem that many users have been very concerned about. Here is how to replace and install the screw correctly and effectively. After reading this article, many of your puzzles will be solved!
The disassembly of the injection nozzle of the injection molding machine is to take advantage of the high temperature after cleaning the inner wall of the barrel and nozzle. First, remove the protective cover outside the barrel, the heater outside the nozzle, and the hot spot coupling to remove the surface material and dust. Use a special hammer to loosen it, and then use a wrench to loosen the connecting bolt. When the connecting bolt is loosened to 2/3, tap lightly with a special hammer. At this time, it is not advisable to loosen all of it, so as to prevent the gas in the barrel from spraying and hurting people; after the internal gas is released, the snow is loosened and the bolt is removed, and then the nozzle is removed.
1. Disassembly of the double alloy screw nozzle of the injection molding machine
If there is leftover material in the barrel, it should be heated to the plasticizing temperature first. Use a polyolefin resin with high thermal stability or a special cleaning material for the barrel to fully carry out high-speed cleaning, and try to discharge the remaining melt before it can be disassembled Work, because it is always impossible to discharge all the residual material in the nozzle, it is necessary to heat the nozzle or the head of the barrel before disassembling the nozzle. After the double alloy screw nozzle of the injection molding machine heats up, tap it with a special hammer to loosen it. The bolts should not be loosened completely. Tap lightly when it is loosened to 2/3. After the internal gas is released, remove the nozzle. The internal cleaning of the injection nozzle of the double alloy screw of the injection molding machine should be carried out while it is hot at a high temperature, so that the residual melt in the runner can be taken out from the nozzle hole. The method is to inject the mold release agent from the nozzle, that is, drip the mold release agent from the side of the nozzle thread to the material and the inner wall surface, so that the material is separated from the inner wall, and the material is taken out from the nozzle.
2. Maintenance and repair of the double alloy screw nozzle of the injection molding machine
If the contact part between the nozzle and the mold positioning sleeve is in single-sided contact or poor contact during production, the spherical R part of the front end will be deformed, forming a groove for melt escape, causing flash at the nozzle, and the caliber part will also appear If it is deformed, it should be inspected and repaired in time if there is a spill.
3. Check the thread of the nozzle regularly
   Focus on checking the condition of the part and the sealing surface on one side of the barrel. If it is found to be worn or corroded seriously, it should be replaced in time.
Fourth, check the internal channel of the double alloy screw nozzle of the injection molding machine
  The surface quality of the molten material strip can be observed by the air injection molding, and the residual molten material discharged from the nozzle can more accurately reproduce the flow channel condition in the nozzle. Thus, the residual amount and temperature distribution of molten material in the nozzle can be analyzed.More about:Parallel twin screw barrel