If there is a one-side contact or poor contact in the contact part between the nozzle and the mold positioning sleeve, the front end spherical portion R will be deformed to form a groove in which the melt escapes, causing the nozzle to overflow, and the caliber portion will also be deformed. Therefore, the occurrence of flash should be checked and repaired in time.
Regularly check the condition of the threaded portion of the nozzle and the sealing surface on the side of the barrel. If it is found to be worn or corroded, it should be replaced in time.
Check the internal passage of the screw nozzle of the injection molding machine. The surface quality of the ejected melt strip can be observed by the air injection molding, and the residual melt discharged from the nozzle can more accurately reproduce the flow path condition in the nozzle. This allows analysis of the residual amount of the melt in the nozzle and the temperature distribution.