Use conditions and methods of extruder barrel screwUse conditions and methods of extruder barrel screw
Extruder screw barrel heating method:
Jane heating widely uses the method of resistance heating, and uses thermocouples to achieve segmented temperature control and inspection side. Resistance heating is the use of resistance to generate heat to heat the barrel, and then transfer the heat to the plastic in the barrel. Resistance heating mainly includes band heaters, cast aluminum heaters, ceramic heaters, etc. These heaters have the advantages of small size, easy production and maintenance.
Extruder screw barrel heating power:
When determining the heating power of the barrel, in addition to considering the heat required during plasticization, it is also necessary to satisfy the productivity requirements of the injection molding machine to ensure that the barrel has a sufficiently fast heating rate. The heating time of the machine heating does not exceed 30min for small machines, and generally about 1h for large and medium-sized machines.
Cooling of screw barrel of extruder:
① Under normal circumstances, the barrel does not need to be equipped with a cooling control system, and natural cooling can satisfy the process requirements. However, if the temperature of the feed inlet is too high, the phenomenon of "bridging" will appear at the feed inlet, making feeding difficult or even impossible.
② In order to ensure that there are excellent feeding and solid material transportation conditions, to avoid the heat transfer of the barrel to the transmission parts, a cooling jacket (slot) should be provided at the feed port of the barrel, and the amount of cooling water can be adjusted according to the process requirements. In addition, when processing heat-sensitive plastics at a higher speed, it is necessary to cool and control the temperature of the machine to avoid the heat-sensitive plastics being differentiated by heat.