Material build up on the die in extrusion 4

[GerardoS]

Hello,

Is there anything that can be done to reduce or eliminate material build up on the die in extrusion process? The material used is a mix of natural rubber with polypropylene.

Thank you!!

 

[NickE]

Coat your die w/ a very slippery material that doesn't allow build up to occur. PTFE comes to mind. Finer polish might help also.

nick

 

[Carburize]

A number of companies such as

http://www.magnaplate.com

offer specialized coating which prevent material pick-up on dies.

 

[GerardoS]

Thank you for the tips Nick and Carburize, it makes a lot of sense, however, the die is already coated with PTFE and I still get material build up. I thought of adding an additive during mixing, but I don't know if there is any appropriate.
Thanks again
Gerardo

 

[etch]

okay here sia method we used, for castings, as well as coatings. On a refular basis, we blasted the dies with not sand or abrasive material but dry ice, this removed all crud and left die clean. it also reduced die temps.

its quite expensive, but compared to time lost lifitng out dies to clean them its a good cost saving.

 

[mx2mx2]

There is an extremely thin coating that you can apply to your PTFE coating that should help with reducing material buildup in your die. I have used it in a hot stamping process on plastics with great success. It is

http://www.kiss-cote.com.

Malcolm

 

[unclesyd]

You need to look at this product that can be used without any disassembly of the equipment. It maybe useful on your existing equipment.
There were several purging compounds out there but we used this one with good results.

http://www.rapidpurge.com

 

[superpat51022]

we have try ac wax fron schulman with good succes(1%) in the mix.

patrick De Belder