What can we do when the short shot happen?

Several factors affect the ability of the polymer to fill the cavity. When the short shot is more obvious, proper remedial measures can be used. The following are some suggestions.
Modify product design
It is important to modify the flow path to eject the polymer; this way to mitigate the mitigation of
short shots.
Appropriately increase the wall thickness of a certain area.
Modify the mold design
A properly designed transmission system (inlet, runner, sprue) will promote a more balanced filling pattern. If necessary, modify the design as follows.Fill the wall thickness before filling the thin-walled area. This will avoid the solidification of the polymer caused by fouling.
Increase the number and size of gates to reduce the length of the runner.Increase the size of the runner system to reduce drag
The trapped air (air trap) in the cavity can also cause short shots.Increase the venting holes in the proper position, especially in the last filled area.Increase the size and quantity of exhaust.
Adjust molding conditionsNote how the raw material is injected into the mold.Increase injection pressure
Be careful not to exceed the machine’s capacity (performance). The operating injection pressure should be limited to 70~85% of the maximum injection pressure to prevent occasional damage to the machine’s hydraulic system.
Increase injection speedThis creates a more viscous heat within the machine limits that reduces the viscosity of the melt.
Increase injection volumeIncrease barrel and mold wall temperatureHigher temperatures promote the flow of the material through the cavity. Care is taken to avoid temperature degradation and degrade the material.
3. The molding machine may also be the chief culprit in short shots.
Check the hopper to ensure that the feedstock is fully supplied or blocked. Check the non-return stop valve and the barrel for excessive loss.
Loss can lead to the loss of injection pressure and the loss of injection volume.

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