What are the advantages of twin-screw granulator compared with single-screw granulator?


The twin-screw granulator and the single-screw granulat […]

The twin-screw granulator and the single-screw granulator are two different machines, but in terms of performance, the twin-screw granulator has more advantages. So do you know what advantages the twin-screw granulator has compared to the single-screw granulator, and how to determine its diameter?

1. The material conveying efficiency of a single screw depends on the friction performance of the solid material and the viscosity of the melt. In the twin-screw granulator, the conveying of materials is carried out by the principle of positive displacement, and no pressure reflux is generated.
2. Due to the short screw length of the twin-screw granulator, the material stays in the twin-screw granulator for a short time. This aspect can avoid the occurrence of thermal degradation of the recycled material fiber and reduce the power consumption.
3. The plastic material has excellent homogenization and plasticization effect after longitudinal and transverse shearing and mixing.
4. The twin-screw granulator has excellent exhaust and self-cleaning functions.
5. The flow rate of the twin-screw pelletizer is not sensitive to the die pressure, and it is more effective to extrude products with large sizes and areas. The flow rate of the single-screw granulator is more sensitive to the die pressure.

How to determine the diameter of the twin-screw granulator?
1. The specifications of the twin-screw granulator are represented by the screw diameter D. In order to meet the requirements of "three modernizations" (serialization, standardization and generalization), the screw diameter of the granulator in my country has been serialized.
2. At present, the diameter of the screw of the molding granulator produced in the world is mostly below 300mm, and the diameter of the screw of the granulator used for granulation or mixing is about 150-600mm, and the larger one has reached 750mm.
3. In most cases, the screw diameter is determined according to the output requirements of the unit, and the output is determined by the specifications of the products produced by the unit.
4. For example, the productivity Q of the tube extrusion unit, film extrusion or plate extrusion unit can be calculated by the corresponding formula, and other units can derive the corresponding formula by themselves.
5. According to the regulations of my country's granulator standard, the diameter of the granulator is 30, 45, 65, 90, 120, 150, 200, 250 and 300mm.