What is Suck Back?

[NskNsk]

Hi Friends,
I'm a beginner for injection molding machine(plastic).Now I'm working in a factory that has several plastic injection molding machine.
I haven't fully awareness about molding machine process.
What is suck back step of the cycle?

Please,anyone can describe or give a descriptive link about injection molding machine process step one by one?

Thank in advance

[moldingppm]

Suck back is another term for decompression. Basically it moves the screw straight back to a set point to keep pressure out of the tip of the barrel. This keeps stringing and such to a minimum.

[NskNsk]

Thanks for answer.
What are reasons for keep pressure out of the tip of the barrel?
according to my experience there are two suck back steps.one for screw at the front. another one screw at the back position.

[Airwinghma]

Dude do a search on YouTube for injection molding operation.


https://www.youtube.com/watch?v=eUthHS3MTdA

Scott

[NskNsk]

thanks Scott.