Dear colleagues,

I have question:
Do You have experience with wearing out of the barrel? Or have You ever been forced to solve problems at parts by changing of the barrel?

I have large product from PP long glass fiber (mixing 60%LGF 1,5mm pellets with Nonfilled granulated PP at gravimeter to concentration 30% in (melt) part).
The glass content in the final product is ok but problem is in its distribution where clusters of non-dispergated glass fibers appear on the surface and comes thru the whole thickness of the part. Although the part is non visible, the nondistributed glass content in some area causes that the part is scrap and can´t be used in next process.

We´ve tested a lot. Even with the changing of the screw by new special one for glass content = no change. Than put back the old refurbished = no change. Closing ring is ok, no wearing.
The last thing that had never been changed is barrel itself.

But I dont want to misslead You in decission by this, just asking about experience and possible cause of poor distribution of glass content in the part


I´v contacted supplier as well as the other IM producers - yet without clear answer.

Thanks for reading/comments in advance.

J.