The process is T-die and base resin is PP. Temp. condition is 300 degree, Line speed is 100rpm. MIF is 15~18g/10min. The PP composite is including Recycling PP about 30%. We can not reduce the recycling PP content. The surging problem is a real pain in the neck. Please help me.
And I confuse the surging with Melt fracture.. I am sure that that problem is surging trouble. But What is melt fracture? Are those same problems or Not ?
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R
Rolf Wissmann
Extrusion surging or melt fracture can be caused by feedstock, feeding, = conveying and/or melting issues, which you may have to address step by = step. I suggest you get your hands on books like the following, for = troubleshooting advice:
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sample page
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Go to "
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" and search for "extrusion surging" to = "surge suppression" to obtain book-links to:
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?id=3D2KSbTcdYv9QC&printsec=3Dfrontcover&sour=ce=3Dgbs_summary_r&cad=3D0#PPA1496,M1 On melt fracture see:
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Additives for eliminating melt fracture are suggested here:
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In short: could your surging problem be related to:
"too large" differences in pellet shape and/or size between virgin and = recycled PP
"wrong" feeding zone design
"wrong" screw design and/or screw vs barrel surfaces=20
"wrong" temperature profile
...
canizaro wrote:
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