| 摘要 |
A center heated die plate (10) for an underwater pelletizer radiates heat outwardly to the extrusion orifices (20) and die faces of the die plate thereby maintaining the die plate (10) and extrusion orifices (20) at an elevated temperature to obtain optimum flow of molten polymer through the extrusion orifices. In one embodiment, a centrally located heating plate (26 ) is mounted in a recess (24) on the upstream face (18) of the die plate (10) inwardly of the nose cone (16) . In a second embodiment, a cylindrical heati ng coil (70) is placed in a hollow central core (62) of the die plate (60) between the nose cone (74) on the upstream side (64) and an insulation plug or plate (82) on the downstream side (66) . Heating leads (34, 76) extend throu gh a single radial hole (36, 78) in the die plate (10, 60) to provide power to the center heating element (26, 70) . |
