Nozzle VS Drooling/Stringing effects
Nozzle VS Drooling/Stringing effects
(OP)
I'm working on a hot runner prototype for our injection-blow molding process and now I must find a way to make nozzles that will not drool or at least, that will reduce it. And we cannot use shutoff nozzle.
With my experience, I saw that if the nozzle have an angle gate, it tend to reduce drooling. But why? I know that the melt flows from the inside to the outside like rolling but how can an angle gate make less drooling?
Here is an image to show what I'm talking about :
With my experience, I saw that if the nozzle have an angle gate, it tend to reduce drooling. But why? I know that the melt flows from the inside to the outside like rolling but how can an angle gate make less drooling?
Here is an image to show what I'm talking about :






RE: Nozzle VS Drooling/Stringing effects
Are you molding Nylon ?
Note
You may want to check the reverse tapper nozzle design (it will help with drool and stringing)
Also you may want to develop your Temperature of Melt vs Viscosity curve for the most otimum Fill Time and Melt Temperature
You may want to check the length of your tips (hot runner) -
RE: Nozzle VS Drooling/Stringing effects
RE: Nozzle VS Drooling/Stringing effects
RE: Nozzle VS Drooling/Stringing effects
For materials with a tendency to string, very accurate temperature control of the nozzle, with voltage up down (not on off) or PID type controllers.
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RE: Nozzle VS Drooling/Stringing effects
Styrene stringing? Too cool..
Where is the pic in original post? Might help..
Cheers
Harry
RE: Nozzle VS Drooling/Stringing effects
Here is a link for the pic.
http://www
RE: Nozzle VS Drooling/Stringing effects
Have to register to view image - no thanks. Try a free site eg tinypic.
Cheers
Harry