Injection Molding Increase injection rate. Reduce injection speed.

Injection Molding Increase injection rate. Reduce injection speed.

Mold Design Recommendations Gates 1. Decrease injection rate Mold Design 1. Decrease injection pressure and injection rate Mold Design 1.

Place cold slug wells at the base of the sprue to capture the cold material first emerging from the nozzle. 2. Reduce decompression Mold design 1. Increase cool time Mold design 1.

PREPERM™ Injection Molding A guide to injection molding PREPERM PPE materials Maxxam™ FR Injection Molding

PREPERM™ Injection Molding Maxxam™ FR Injection Molding Injection molding parameters, startup and shutdown, mold design and troubleshooting recommendations for LubriOne™ Internally Lubricated Formulations

Long fiber composites, in particular, are well-suited for replacing metal, offering exceptional strength-to-weight ratio and the ease of injection molding, which can expand design options and streamline processing steps.   The resulting virtual and technical insight allows part designers to: create rapid part design iterations

Long fiber composites, in particular, are well-suited for replacing metal, offering exceptional strength-to-weight ratio and the ease of injection molding, which can expand design options and streamline processing steps.   The resulting virtual and technical insight allows part designers to: create rapid part design iterations

PREPERM™ Injection Molding A guide to injection molding PREPERM PPE materials Maxxam™ FR Injection Molding

MOLD DESIGN RECOMMENDATIONS Gates • Many different types of gates can be used, such as fan, tunnel, tab, and edge gates. • Moderate gate size according to the part geometry. Cold Slug Wells • Place these wells at the base of the sprue to capture the cold material first emerging from the nozzle. • Place wells at every 90° bend in the runner system. • Well depths approximately 2.5 times the diameter of the runner provide the best results. Sink Marks Melt too hot • Decrease nozzle and barrel temperatures • Decrease mold temperature Insufficient material volume • Adjust transfer position • Increase shot size • Increase injection rate • Increase packing pressure Part geometry too thick • Reduce wall thickness • Reduce rib thickness TROUBLESHOOTING RECOMMENDATIONS PROBLEM CAUSE SOLUTION Flash Injection pressure too high • Decrease injection pressure • Increase clamp pressure • Decrease injection rate • Increase transfer position Excess material volume • Adjust transfer position • Decrease pack pressure • Decrease shot size • Decrease injection rate Melt and/or mold temperature too hot • Decrease nozzle and barrel temperatures • Decrease mold temperature Loose clamp • Reset mold height • Increase clamp tonnage Shrink Too much shrink • Increase cooling time • Decrease mold temperature Too little shrink • Decrease cooling time • Increase mold temperature Burning Process related • Decrease nozzle and barrel temperatures • Decrease mold temperature • Decrease injection rate • Reduce decompression Mold design • Clean, widen and increase number of vents • Increase gate size to reduce shear Wet material • Verify material is dried at proper condition Nozzle Drool Nozzle temperature too hot • Decrease nozzle temperature • Decrease back pressure • Increase screw decompression • Verify material has been dried at proper conditions Incorrect nozzle • Use reverse taper tip Weld Lines Melt front temperatures are too low • Increase injection rate • Increase pack and hold pressure • Increase melt temperature • Increase mold temperature Mold design • Increase gate size • Identify end of fill pattern and verify proper vent location • Add vents or increase vent width • Move gate location TROUBLESHOOTING RECOMMENDATIONS PROBLEM CAUSE SOLUTION Warp Process related • Increase melt temperature • Reduce injection speed • Increase pack pressure • Increase pack time • Decrease mold temperature • Increase cool time Mold design • Non-uniform mold cooling Part design • Non-uniform wall thickness Thermolator incorrect temperature • Check settings • Inspect thermocouple Sticking in Mold Overfilled cavity • Decrease injection rate and pressure • Decrease hold pressure • Adjust transfer position • Decrease nozzle and barrel temperatures • Decrease mold temperature • Decrease cooling time Part too hot • Decrease barrel temperature • Decrease mold temperature • Increase cooling time Mold design • Increase draft angle • Polish cores in direction of ejection Black Specks Contamination • Purge machine Degradation • Reduce melt temperature • Reduce screw speed • Reduce back pressure Machine related • Check for wear on screw, barrel or check ring Delamination Process related • Increase melt temperature • Decrease injection speed • Purge barrel to eliminate material contamination Mold design • Reduce sharp corners in material flow path • Increase venting TROUBLESHOOTING RECOMMENDATIONS PROBLEM CAUSE SOLUTION Discoloration Oversheared material • Decrease melt temperature • Decrease injection speed • Reduce residence time Mold design • Increase gate sizing Dry material • Check moisture of material to ensure it is within the recommended moisture percentage for molding TROUBLESHOOTING RECOMMENDATIONS 1.844.4AVIENT www.avient.com Copyright © 2021, Avient Corporation.