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View Full Version : i am using recycled materials, how to eliminate dirt clogged at hot runner tip?



hermanwinata1818
15th December 2012, 02:56 PM
we use recycled material for production. We often have to clean dirt clogged at hot runner tips. I have been trying some hot
runner systems but still have this problem. Any ideas to eliminate this routines?

Pilot
17th December 2012, 04:02 PM
Are U using recyclate as regrind or regranulate?
I suppose, that it will be regrind material. You have to have good metal separator befor screw, which will remove all metal particles. For other dirty you can have a mesh filter insert under nozzle tip (on the barrell). This can be cleaned after nozzle disassembly.

The situation with regranulate is little bit comfortable, because this material is prepared with cleaning procedure.

pjhall
17th December 2012, 06:55 PM
When designing hot runner systems its important to be able to take the bolts out of the cavity plate, close the mold, strap the cavity plate to the core plate, and open the mold and pull the cavity plate to expose the hot runner tips. We call it "de-capping" the tips. Heat the tips up and remove the caps. I would then use an ejector pin and check the tip flutes to make sure all 2 or 3 are open and not plugged. One company I worked for made HVAC automotive vent doors out of Minlon (mineral filled nylon). We had to "decap" quite often when the mineral would build up on the outside of the tips. Purge through the mold (put the back pressure at max and extrude) and you can usually see the restriction.

brentb
18th December 2012, 01:24 AM
Buy an INCOE SPM nozzle/melt filter. They are great! Do purchase filter with filter media smaller (finer) than gate drop size.

KOM

brent

arturo aguirre
2nd January 2013, 07:20 PM
Hi Herman,

is important to control the operation in the grainders as principal solution, but you can use a tram filter nozzle


Regards