Degassing with strands between extruders.

An unusual cascade extrusion line for reclaiming large volumes of low-bulk-density polyolefin waste comes from Davis-Standard Corp., Pawcatuck, Conn. It starts with feed conveyors, a shredder, holding bin, and ram stuffer, and then a 24:1 L/D extruder. Melt is filtered and fed through a melt pipe to a strand die, which drops hot strands into an enclosed hopper chamber above the throat of a 15:1 L/D hot-melt extruder. The intermediate stranding stage in Davis-Standard's Merritt reclaim line exposes about 90% of the melt to degassing vs. only about 30% with a conventional vent port. Fillers and additives can be added at the second extruder. Four cascade reclaim systems with up to 100 holes have been delivered for 3000 lb/hr. Tel: [phone] * PTDirect: 189AP

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