A look inside a plastics granulator

A lot of scrap plastic gets reused in the injection moulding business, but the key is to turn it back into something resembling the original pellets. Simply shredding it into smaller pieces doesn't work well, as flakes and strands can block the feed inlet. So a machine to granulate the material is used. This video shows how they work and how they're used.

[@christopherrumford]

Great explanation and loads of detail.
Thanks for sharing.

[@andyharsley]

Glad you enjoyed it. Thanks for watching!

[@landonsegal4355]

Do you think this would work on a charcoal-like product? turning it from coarse material into a granular?

[@andyharsley]

Probably yes, but I expect it would produce a lot of fine powder as well. Some granulators feed the regrind into a cyclone system which separates the fines. Basically like a big Dyson vacuum cleaner. The dust gets extracted and the heavier granules fall through a funnel at the bottom. So I think it could be done with charcoal.

[@dnjmachine]

Very informative, what did you do before you had the granulator?

[@andyharsley]

I got it when I first set up. The Arburg was an ebay purchase off a dealer selling a load of ex-Lego machines, though I think Auntie came from elsewhere. The granulator (Sir Chopalot) was bought with a load of other equipment from another dealer, and the oven plus a big dryer I don't use are on long-term loan from a friend.

[@bikefarmtaiwan1800]

Thanks for a detailed tour! Very interesting to se the design of this granulator, two wide opposing blades rather than thinner multiblades . Looks like it does a great job. What horse power is that motor?

[@FrodorMov]

Interesting. How the blades work was a bit of a surprise, was expecting something like a shredder with two opposite axes if you know what I mean.

[@andyharsley]

The blade arrangement is clearly the key to getting good granules. They are adjustable, but I've never messed with them to see what happens. I was surprised there isn't more of a scissor action, just a very slightly angle on the rotating blades. The smaller granulators might be different. Will have to check next time I'm at another mould-shop.

[@FrodorMov]

@@andyharsley Yeah I was only familiar with more DIY shredders anyway.