Short shots are products that are not completely injected because the material is not sufficiently injected into the mold. In some cases, short shots are deliberately used to determine or visually fill the pattern. But when the polymer flow cannot fill the entire cavity – in thin walls At the extreme or extreme, it is most likely to produce problematic bad short shots.
Short shot reason
Any factor that increases the flow of polymer or prohibits the transfer of sufficient material into the cavity can cause short shots. Includes:
Restricted areas of insufficient size such as gate runners and thin-walled parts.? Low flow or thin wall temperature.? Lack of venting holes causes gas to mix into the cavity.
The machine does not have enough injection pressure (caused by high flow resistance and restricted flow path), flow or ram speed.
Machine defects such as empty hoppers, blocked feed throats or worn non-returnable stop valves.
Polymer melting caused by raw material blockage and poor filling mode or extended injection time.