PP plastic raw material molding conditions!
PP
Acrylic resin (polypropylene)
Polypropylene Resin
PP material will begin to degrade from around 280°C. Therefore, the heating temperature should be lower than 270°C. Its molecular alignment is very strong. When it is molded at low temperature, it is easy to warp and twist due to molecular alignment.
High-pressure forming machines must be used for high-pressure forming.
Retreat tilt may magnify. Runners and gates must be designed for flowability. Pay attention to the control of material temperature and mold size.
Molding shrinkage rate is about 0.35%, heating temperature is 180~300°C, mold temperature is 20~80°C, tube temperature is 220~270°C, ejection material temperature is 210~280°C, injection pressure is 400~1000kg/cm disease (19) Tong Lu exposed? 00 °C.
Gate design must pay attention to the adhesion of the molded product. Moldings shall be designed to prevent sinking and deformation. Molding shrinkage is about 0.8~1.5%.
Use hot air drying drying temperature of 60 ~ 90 °C, takes 1 hour, the first section of the feed tube temperature is 240 ~ 250 °C; the second paragraph is 190 ~ 250 °C; the third paragraph is 170 ~ 230 °C; the fourth paragraph is 150~210°C; mold surface temperature 20~60°C.
Temperature setting: nozzle 200~220°C, front 190~215°C, middle 190~210°C, rear 185~200°C; screw speed 120~maximum rpm, mold temperature 20~70°C, injection pressure 700~1800°C , extremely long maintenance pressure 30 ~ 70%, back pressure 120 ~ 200kg/cm disease?
Density 0.90~0.91g/cc, specific gravity 0.9~0.92 linear expansion coefficient 0.000058~0.0001/°C, molding shrinkage 1.0~2.5%, heat distortion temperature 57~63°C (96~110°C).
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