1. Preparation: sieving the stabilizer, filler, and col […]
1. Preparation: sieving the stabilizer, filler, and coloring agent with 80 mesh screens, respectively add plasticizer to soak and grind them with a three-roll mill or colloid mill. Standby after weighing. After the plasticizer is evenly mixed, preheat it to 90°C for later use;
2. High mixing machine: Put in PVC resin, then add plasticizer and stir for a while, after the resin basically absorbs the plasticizer, add stabilizer, increase the material temperature to about 90℃ by friction heat, then add filler and color When the temperature of the material rises to 110°C, the material is discharged into the cooling mixer to cool down, and the material is discharged when the temperature is below 45-50°C.
3. Stable setting of PVC granulator:
1) The temperature setting of the upper twin screw: between 140 ---- 160 degrees; the temperature setting is different according to different materials;
2) The stable setting of the lower-order single screw: between 125 and 145 degrees; the setting is different according to the different temperature of the material;
3) Set the temperature control table (see the picture on the right). After the actual temperature reaches the set temperature, it can be kept for 40 minutes before starting production. This is to ensure that there are materials left over from the previous day in the equipment. The remaining material is softened so as not to damage the equipment.
4. Production:
1) After the high-mixer PVC material is put into the hopper of the screw feeder, the powdery material is put into the upper-stage parallel twin screw extruder through the screw feeder
2) The upper-stage parallel twin-screw extruder mixes the materials uniformly, and completes the plasticization and mixing at a temperature of 140-160℃, and fully disperses them evenly. Finally, the extruded mixture material becomes a melt (temperature at 130-140°C) and directly falls into a large-diameter lower-stage single-screw extruder.
3) The lower-stage single-screw extruder extrudes and pelletizes the melt at 120°C under low speed, high pressure and cooling conditions. The temperature has dropped to 120-140°C during extrusion. Only then can the hot pelleting of the air-cooled die surface be completed, and the pellets will not stick during the pelletizing process.
4) The eagerly cut particles from the air-cooled mold surface are cooled by a secondary air-cooled cyclone, the particle temperature is reduced to 35-40 ℃, and then through the air-cooled extended vibrating screen, the particle temperature is reduced to room temperature for delivery to the finished product Silo for packaging.
