The water ring hot cutting plastic granulation unit of Keda Company in Laizhou City is mainly suitable for different plastics such as HDPE, LDPE, ABS, PPR, PC, PVC, etc. The advantages of water ring granulation are: no need for pulling, no fear of breakage, strong adaptability to materials, and simple operation. The host is an extruder, which consists of an extrusion system, a transmission system, and a heating and cooling system. Vigorously develop renewable resources and turn waste into treasure.

1. Extrusion system The extrusion system includes a hopper and a head. Plastic is plasticized into a uniform melt through the extrusion system, and under the pressure established during this process, it is continuously extruded by the screw head.

(1) Screw: It is the most important component of the extruder, which directly affects the application range and productivity of the extruder. It is made of high-strength and corrosion-resistant alloy steel.

(2) Barrel: It is a metal cylinder, generally made of alloy steel or composite steel pipes lined with alloy steel with high heat resistance, pressure resistance, durability, wear resistance, and corrosion resistance. The combination of the barrel and screw achieves the crushing, softening, melting, plasticizing, venting, and compaction of plastics, and continuously and uniformly delivers the rubber material to the molding system. The length of the general barrel is 15-30 times its diameter, in order to ensure that the plastic is fully heated and plasticized.

(3) Hopper: The bottom of the hopper is equipped with a cutoff device for adjusting and cutting off the material flow, and the side of the hopper is equipped with a sight hole and a calibration measuring device.

(4) Head and mold: The head is composed of an alloy steel inner sleeve and a carbon steel outer sleeve, and the head is equipped with a forming mold. The function of the machine head is to convert the rotating plastic melt into parallel linear motion, uniformly and smoothly introduce it into the mold sleeve, and give the plastic the necessary molding pressure. Plastic is plasticized and compacted inside the barrel, and flows through a porous filter plate along a certain channel through the neck of the machine head into the forming mold. The mold core and sleeve are appropriately matched to form a circular gap with a continuously decreasing cross-section, allowing the plastic melt to form a continuous and dense tubular coating layer around the core wire. To ensure a reasonable plastic flow channel inside the machine head and eliminate dead corners where plastic accumulates, diversion sleeves are often installed. To eliminate pressure fluctuations during plastic extrusion, pressure equalization rings are also installed. The machine head is also equipped with a device for mold calibration and adjustment, which facilitates the adjustment and correction of the concentricity of the mold core and sleeve.

2. The function of the transmission system is to drive the screw and supply the torque and speed required by the screw during the extrusion process. It is usually composed of an electric motor, a reducer, and bearings.

3. Heating and cooling devices are necessary conditions for the plastic extrusion process to proceed.

(1) In 2013, extrusion machines commonly used electric heating, which is divided into resistance heating and induction heating. The heating element is installed on the body, neck, and head of the machine. The heating device heats the plastic inside the external heating cylinder to achieve the temperature required for process operation.

(2) The cooling device is set up to ensure that the plastic is within the temperature range required by the process. Specifically, it is to eliminate the excess heat generated by the shear friction of the screw rotation, in order to avoid excessive temperature that may cause plastic decomposition, burning, or difficulty in shaping. Barrel cooling can be divided into two types: water-cooled and air-cooled. Generally, air-cooled is more suitable for small and medium-sized extruders, while water-cooled or a combination of both forms of cooling are more commonly used for large extruders; Screw cooling mainly adopts central water cooling, aiming to increase the solid material conveying rate, stabilize the adhesive output, and improve product quality; But the cooling at the hopper is to strengthen the conveying effect of solid materials, prevent plastic particles from sticking and blocking the material mouth due to temperature rise, and ensure the normal operation of the transmission part.