What’s nozzle of injection machine?

nozzle structure

Nozzle is the front part of the screw and barrel of injection molding machine, it is the necessary and important of injection machine.

injection molding machine nozzle function

  1. while injection machine doing charging,establish back-pressure,drive out the air, prevent melt material flow out, and improve the plasticizing ability and measurement accuracy.
  2. During injection,touch the main sprue of the mold and keep good connection and form close passage to prevent the melt material flow out under high pressure.
  3. when machine do injection, help establish melt pressure,increase shear stress,also help increase shearing speed and temperature rise,enhance mixing effect and homogenization.
  4. nozzle also help the temperature regulation,heat preservation and material breakage.
  5. reduce the viscoelastic effect and eddy current lose of melt material at the inlet and outlet in order to stablize its flow.
  6. while injection machine doing pressure-holding, it help feed the material into the molded product. while cooling, it help increase return resistance, reduce or prevent the melt material flowing back from mold cavity.

What’s the hole diameter of nozzle?

Generally, different size injection molding machine, different nozzle hole diameter. For example, for small injection machine, it has 2.5mm,3mm,4mm; for big machine, it will be 6mm,8mm,10mm,etc.