Which one is better, single screw or twin-screw granulator?
A plastic granulator is a kind of mechanical equipment used for plastic recycling and processing, and it is widely used and divided into single screw granulators and twin screw granulators.
The twin-screw granulator is mainly divided into two categories: parallel and conical twin-screw. Compared with a single screw plastic granulator. The twin-screw granulator has the following five characteristics during granulation and molding processing:
1. In the twin-screw extruder, the conveying of materials is carried out by the positive displacement principle, and no pressure reflux will occur. Therefore, it is easier to add materials. The material conveying efficiency of a single screw mainly depends on the solid materials' friction properties and the melt's viscosity.
2. Since the screw length of the twin-screw pelletizing extruder is relatively short, the residence time of the material in the twin-screw extruder is short, which avoids the thermal degradation of the recycled materials and reduces the power consumption of the equipment.
3. The plastic has an excellent plasticizing effect after vertical and horizontal sharing and mixing.
4. The twin-screw granulator has excellent exhaust and self-cleaning functions.
5. The twin-screw pelletizing extruder can be used to extrude products of considerable size and area.
What is the difference between a single-screw granulator and a twin-screw granulator?
1. The heating method of the main barrel of the single-screw granulator is mainly electric heating, and the temperature of the barrel is automatically controlled by the water cooling method. The core of the screw can be cooled by passing water or heat transfer oil to control the temperature of the screw.
2. The twin-screw pelletizer is mainly used for filling, modifying, chlorinated rubber and engineering resins, and processing polypropylene and water-absorbent resins; degradable masterbatch, extruding polyamide polycondensation reaction, and polyurethane addition polymerization reaction product.
3. The barrel and screw of the parallel twin-screw granulator are designed according to the building block principle and can be combined in different ways as required. It adopts electric heating and water cooling methods to automatically control the temperature of the barrel and is equipped with forced feeding, vacuum exhaust, and non-stop screen-changing devices.
4. The twin-screw granulator adopts variable frequency speed regulation, AC motor drive or DC speed regulation, DC motor drive. The deceleration and the twin-screw movement happen in the same box, and the appearance is compact. The safety coupling is used to protect the screw and transmission box from damage due to overload.
After the material passes through the feeding port, under the action of the rotating screw, it is rolled into a dough shape and then moves forward along the screw groove. Due to the sheer compression and agitation of the screw, the material is further mixed and plasticized, and the temperature and pressure rise slowly. , Presents a viscous state, and passes through the machine head with a certain pressure and temperature, and finally obtains the desired shape of the finished product.
Precautions for the operation of plastic granulator:
1. When filling, do not have debris in the material, master the temperature, do not use residues with metal materials or low-quality recycled materials, and do not place metal objects that may fall into the filling port around the feed port to prevent it from causing damage. Jamming or destruction problem.
2. During the actual operation of the plastic machinery and equipment, the material temperature has not reached the set temperature, and the heat preservation time is not enough; it is not allowed to start the extruder screw.
3. When operating the plastic granulator, strictly follow the requirements of the operating procedures to ensure the reliability of the safe device.
4. Operators need to be trained and familiar with the structure and performance of plastic machinery and equipment before they can carry out actual operations. The correct use of the plastic granulator can significantly reduce mechanical failures and mechanical equipment damage caused by incorrect operation of the machine and significantly extend the life and reliability of the equipment.