Runner recycling

[martijnjanssen]

Hello all,

I'm doing my internship at a injection molding company.

Now a project of mine is to think about the recycling of runners. They gave me some information about it
maximum 30% runners mixed with the virgin material
fresh start each week (0% runners mixed with the virgin material)
material is PA

If 1st lot runners are used in the 2nd lot, and 2nd lot runner in 3 lot, and so on.. How many times can I reuse the runner (Not depending on product or application)?
Do you just grind it down or use additives (chemical recycling)?

If someone has any information about it, could guide me in this or can refer me to any articles about it , it will be greatly appreciated.

Thank you

Martijn

[Suhas]

Hello Martijn,
If you can get your hands on a copy of my book, please read pages 207 to 210. I also give out a free software with tools for Scientific Molding and one of the calculation tools is to calculate the pass and generation of the regrind in the part for the closed loop system. You will be actually surprised to find that if the ratio of the part weight to runner is high, you can run the system forever. Please send me an email at suhas@fimmtech.com and I will send you a link to download the software.
Mr. Bozzelli also wrote a good article in Plastics Technology I believe.
Regards,
Suhas

[Jendalf]

Hi,
What grade of PA it is? Filled/nonfilled.
And what are the demands on the final product?

Recycling of the PA is more difficult as the PA polymer is prone to degradation due its thermal coditions during processing.

Anyway its always good to test the theory again.

hf
j

[brentb]

Start with dry material and keep dry (including regrind)

KOM

brent

[martijnjanssen]

@Jendalf the material is PA66 , not sure what you mean by filled/no filled, but its only the PA66 that's going into the feed hopper

@Suhass thanks for the software, but I'm not sure how to interpret the results I'm getting.

Also I'm putting this project on hold for a little bit to focus on the product collection project.
Thanks for all the help so far guys, it is greatly appreciated.