Injection Molding
Injection Molding
(OP)
Does anybody knows about a software simulation for expanded polypropylene molding injection?
I am looking for this simulation because I am working in processing expanded polypropylene (injection molding)and I want to better estimate the cooling time.Or any method to estimate cooling time for this material
Thank you!
I am looking for this simulation because I am working in processing expanded polypropylene (injection molding)and I want to better estimate the cooling time.Or any method to estimate cooling time for this material
Thank you!






RE: Injection Molding
For a solid PP you know the heat required as it just depends on the amount of material.
For a foamed system it will depend on that plus the influence of the foam which insulates the material. You'd need to know the insulation effectiveness of the foam (depends on cell size). Also, the foam is not even throughout the sample. There should be a skin on the outside with no bubbles in it.
As a non-expert in cycle time I'd say that sounds hard to estimate from calculations. Far better to get input from the polymer manufacturer or someone with a lot of experience molding those materials.
Chris DeArmitt PhD FRSC CChem
RE: Injection Molding
Regards
Pat
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RE: Injection Molding
RE: Injection Molding
It would vary by apparent SG so a lot of extra data would be required.
I am sure sometimes something like this happens and I don't see or hear about it, however in this case I doubt it for the reasons mentioned above.
Regards
Pat
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RE: Injection Molding
If memory serves, we were ultimately able to hold cycle time at pre-blowing agent parameters by throwing the part into cold water upon ejection. It was neither a grand nor ideal operation, right from the beginning, but we got it to work and learned a lot from it.
You might consult with a structural foam operation for some better insight.
It is better to have enough ideas for some of them to be wrong, than to be always right by having no ideas at all.
RE: Injection Molding
Molding expanded polypropylene (EPP) suppose (in short) to fill the cavity with beads(pellets) of expanded propylene by means of pressure in a fill gun, steaming the mold, cooling it and then ejecting the parts(automotive parts). My question is how can I optimise all these steps(simulation programs, statistical methods, rules of thumb, etc..)
Thanks!
RE: Injection Molding
Chris DeArmitt PhD FRSC CChem
RE: Injection Molding