Suitably-heated mold cavity mold gate channel and divergent machine nozzle opening are filled with melt held at constant temperature. Suitably-heated mold cavity (6), mold gate channel and divergent machine nozzle (3) opening, are filled with melt held at constant temperature. Following injection, heat is removed, setting the melt. To compensate shrinkage, dwell pressure is applied. The divergent nozzle opening is cooled, setting the melt inside, forming a sprue. This is removed from the nozzle, by raising the injection tool. It is pulled out, still bonded with the molding. The sprue is torn away from the melt at the transition region into the hot injection chamber. Sprue (8), including set plastic in the mold gate channel, is removed mechanically, tearing it away close to the molding at a constriction. Preferred features: To get the principal molding out, platens part; in so doing, the mold assembly including the sprue channel, again comes to rest against the injection nozzle. The molding is extracted mechanically from the closure side mold platen. Melt dribbles from the injection nozzle collect low in the gate channel section, and are excluded from the next injection cycle, maintaining molding quality. To complete the cycle, this platen is closed up to the sprue platen (still against the nozzle) and re-heating takes place.
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