Equipment for converting scrap solid thermoplastic material into a regular granular form comprises a rigid heated grid on top of which the matl. is placed and through which it is forced by an overhead press plate, so that the matl. passes through the grid because of local fusion at the borders of each opening. The strands emerge within an enclosure where they are kept gently moving mechanically until chilled by forced draughts. Pref. the grid is made from a series of strong intersecting blades electrically heated to a controlled temperature. Used for recovery and reprocessing of sprues, runners, offcuts from film etc. with minimal risk of degradation or contamination. Simpler in construction and more energy efficient than processes which involve total fusion and face cutting or hammer milling, esp. for high mol. wt. high density matls. of high strength and low elasticity.
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