(1) eliminate the interference of gas and other impurities, and fully dry the plastic.
(2) reduce the feed temperature, adjust the feed barrel temperature in stages, and appropriately increase the mold temperature.
(3) increase the injection pressure and reduce the injection speed.
(4) increase or decrease the preplasticized back pressure, reduce the screw speed.
(5) improve the exhaust condition of the flow passage and cavity.
(6) clean up possible blockage of nozzle, runner and gate.
(7) shorten the molding cycle, demoulding after annealing method to eliminate crazing available: to keep polystyrene at 78 ℃ for 15 minutes, or keep 1 hour 50 ℃, the polycarbonate, heated to 160 ℃ or more stay for a few minutes.