Conditions and method of use of Screw and Barrel for Pelletizer Machine

During the plasticizing process of the injection molding machine, the screw groove of the screw and barrel for Pelletizer Machine is usually very deep, so the friction and shearing of the material and the cylinder during rotation generate relatively little heat, and the heat required to dissolve the plastic is in addition to the self. In addition to the shear heat generated by the rotation, most of it mainly depends on the heating of the cylinder block. Then, let's learn about the operating conditions and methods of Screw and Barrel for Pelletizer Machine!

1. Cylinder heating method of Screw and Barrel for Pelletizer Machine
Simple heating widely adopts resistance heating method, and uses thermocouple to realize step-by-step temperature control and detection end. Resistance heating refers to the use of heat generated by electrical resistance to heat the cylinder to a large extent, and then transfer its heat to the plastic inside the cylinder. Resistance heating mainly includes strip heaters, cast aluminum heaters, ceramic heaters, etc. These heaters have the advantage of being small and easy to manufacture and maintain.
2. Temperature range of Screw and Barrel for Pelletizer Machine
In order to make the dissatisfaction distribution of the cylinder meet the requirements of the injection molding process according to the different plasticizing states of the material along the axis of the screw, the simple heating of the screw must be carried out gradually, which is conducive to the improvement of the plasticizing ability. Usually, (3-5) Ds, ) Ds as the diameter of the rod) as the heating temperature control section, the heating temperature control fluctuation range is usually not more than 5, and preferably 2 or less for heat-sensitive plastics.
3. Screw and Barrel for Pelletizer Machine heating power
When determining the heating power of the barrel, in addition to meeting the heat required for plasticization, it is also necessary to meet the work efficiency requirements of the injection molding machine to ensure that the barrel has a fast enough heating rate. The heating time of machine heating is less than 30min compared to small machines, but usually about 1h compared to large and medium machines.
4. Cooling of Screw and Barrel for Pelletizer Machine
Generally, there is no need to install a cooling depression control system on the cylinder, and the process requirements can be met by natural cooling. However, if the temperature of the supply port is too high, the "cross-linking" phenomenon will occur in the supply port, making it difficult or even impossible to supply.
In order to ensure good feeding and conveying conditions of solid materials and prevent the heat of the cylinder from being transferred to the transmission parts, a cooling jacket (groove) is set at the feeding port of the cylinder, and the amount of cooling water can be adjusted according to the process requirements. In addition, in order to prevent thermal decomposition of heat-sensitive plastics when processing heat-sensitive plastics at higher speeds, the cooling temperature must be controlled.
The cylinder of the Screw and Barrel for Pelletizer Machine is the same as the screw in the extrusion molding system of the plastic pelletizer, and is an important part of the plastic pelletizer. The cylinder and the screw work in cooperation with each other, the cylinder contains the screw, and the screw rotates in the cylinder. As the plastic moves forward in the cylinder due to the rotation of the screw, it is heated and transferred from outside the cylinder to the plastic in the cylinder. The thread volume of the screw is gradually reduced, and the plastic in the thread groove is evenly mixed and refined by various forces such as extrusion, overturning and shearing, and then moves to the front of the cylinder.
The above is the use conditions and methods of Screw and Barrel for Pelletizer Machine. If you want to know more, please feel free to contact us!