Part have a join line!

[Rob_Hoang]

Hello everyone,

I am a new with injection molding process and just started. Currently, I am having a problem with the molded parts, there is a join line on the surface of the finished parts. Before we have been running with same parameters and conditions but the parts still good. I dont know why this time it happened. Please kindly see the below picture:




Can anyone know and give me some advice on how to solve this problem?

Thank you in advanced!

Rob

[rickbatey]

Please share some process settings with us and answer these quick quick questions. Does the mold have any valve gates? Does the mold have multiple gates to fill the part? Can you confirm that the water circuits and flow directions, plus temperature settings, are the same? You are NOT using intrusion or flow molding to partially fill the part? No changes to the mold?
I feel that your melt front advancement has changed and I believe that you have multiple gates. One of these gates is not flowing (blocked by tramp metal, wood or even cardboard) and creating this flow line.
Rick

[Jendalf]

Hi,
it seems that your materialflow during cav. filling has stopped form some reason.
check where you are at switchover (switch of holding pressure)
also check the temperature management (tool temperation; heaters (machine, tool)).

if the tool is complex and you inject thru several inj. points or even with cascade system i dont know.
So you can maybe also add better description and detailed photo.

J.