US 7,320,585 B2
Device for the hot granulation of thermoplastic polymers
Alessandro Casalini, Mantova (Italy)
Assigned to Polimeri Europa S.p.A., Brindisi (Italy)
Appl. No. 10/498,015
PCT Filed Dec. 05, 2002, PCT No. PCT/EP02/13785
§ 371(c)(1), (2), (4) Date Jan. 05, 2005,
PCT Pub. No. WO03/053650, PCT Pub. Date Jul. 03, 2003.
Claims priority of application No. MI2001A2708 (IT), filed on Dec. 20, 2001.
Prior Publication US 2005/0123638 A1, Jun. 09, 2005
Int. Cl. B29B 9/10 (2006.01)
U.S. Cl. 425—464  [425/67; 425/311; 425/378.1] 14 Claims
OG exemplary drawing
 
1. A device for the hot granulation of thermoplastic polymers, optionally expandable, which consists essentially of:
a) a die, consisting of a cylindrical body having a thermostat-regulator for maintaining the die at a temperature close to or higher than the softening point of the polymer, containing on the outer surface a plurality of small plates, equipped with a plurality of extrusion holes, and a plurality of feeding ducts of the molten polymer, situated inside the cylindrical body in correspondence with and connected to the perforated small plates, lined with a material having a high thermal conductivity;
b) a cutting chamber comprising a set of spraying nozzles which create a jet of drops of a themostat-regulating liquid used for cooling and removing of the cut granules, nebulized and sprayed against the die;
c) a cutting system comprising a cutting plate, firmly constrained to a rotating shaft, supporting a set of knives arranged so that the cutting profile of the knife is radial with respect to the surface of the die which faces said cutting system.