GRANULATING DIE FOR SYNTHETIC RESIN

PROBLEM TO BE SOLVED: To improve the heat insulating effect on the surface of a granulating die which faces the circulating water of a circulating box, prevent a nozzle hole from excessively being cooled by the circulating water, and prevent the nozzle holes from being clogged by attaching holding plates having a vacuum insulating layer on the die surfaces on the outside and the inside from a hardening layer. SOLUTION: A molten resin from an extruder passes through a die head, and is made into a cylindrical shape by a large number of nozzle holes 2 of this granulating die, and extruded into a circulating box. The surface of the granulating die is cooled because it is in contact with circulating water, but for the surface of a hardening layer 13 where the nozzle holes 2 are formed, a vacuum insulating layer 4 is formed on the surface side of the granulating die, while being adjacent to a heating jacket 3, and the cooling is shut off, and the nozzle holes 2 can be sufficiently heated by a heated fluid which passes in the heating jacket 3. Also, on the external surface and internal surface of the hardening layer 13, external and internal holding plates 14, 18 which are respectively vacuum-insulated, are provided, and the temperature of the overall granulating die does not decrease.